Updating go depencancies. Switching to go1.6 vendoring (#2949)

vendor/github.com/gorilla/context/.travis.yml

@@ -0,0 +1,18 @@
+language: go
+sudo: false
+
+matrix:
+  include:
+    - go: 1.3
+    - go: 1.4
+    - go: 1.5
+    - go: 1.6
+    - go: tip
+  allow_failures:
+    - go: tip
+
+script:
+  - go get -t -v ./...
+  - diff -u <(echo -n) <(gofmt -d .)
+  - go vet $(go list ./... | grep -v /vendor/)
+  - go test -v -race ./...

vendor/github.com/gorilla/context/LICENSE

@@ -0,0 +1,27 @@
+Copyright (c) 2012 Rodrigo Moraes. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+	 * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+	 * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+	 * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

vendor/github.com/gorilla/context/README.md

@@ -0,0 +1,7 @@
+context
+=======
+[![Build Status](https://travis-ci.org/gorilla/context.png?branch=master)](https://travis-ci.org/gorilla/context)
+
+gorilla/context is a general purpose registry for global request variables.
+
+Read the full documentation here: http://www.gorillatoolkit.org/pkg/context

vendor/github.com/gorilla/context/context.go

@@ -0,0 +1,143 @@
+// Copyright 2012 The Gorilla Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package context
+
+import (
+	"net/http"
+	"sync"
+	"time"
+)
+
+var (
+	mutex sync.RWMutex
+	data  = make(map[*http.Request]map[interface{}]interface{})
+	datat = make(map[*http.Request]int64)
+)
+
+// Set stores a value for a given key in a given request.
+func Set(r *http.Request, key, val interface{}) {
+	mutex.Lock()
+	if data[r] == nil {
+		data[r] = make(map[interface{}]interface{})
+		datat[r] = time.Now().Unix()
+	}
+	data[r][key] = val
+	mutex.Unlock()
+}
+
+// Get returns a value stored for a given key in a given request.
+func Get(r *http.Request, key interface{}) interface{} {
+	mutex.RLock()
+	if ctx := data[r]; ctx != nil {
+		value := ctx[key]
+		mutex.RUnlock()
+		return value
+	}
+	mutex.RUnlock()
+	return nil
+}
+
+// GetOk returns stored value and presence state like multi-value return of map access.
+func GetOk(r *http.Request, key interface{}) (interface{}, bool) {
+	mutex.RLock()
+	if _, ok := data[r]; ok {
+		value, ok := data[r][key]
+		mutex.RUnlock()
+		return value, ok
+	}
+	mutex.RUnlock()
+	return nil, false
+}
+
+// GetAll returns all stored values for the request as a map. Nil is returned for invalid requests.
+func GetAll(r *http.Request) map[interface{}]interface{} {
+	mutex.RLock()
+	if context, ok := data[r]; ok {
+		result := make(map[interface{}]interface{}, len(context))
+		for k, v := range context {
+			result[k] = v
+		}
+		mutex.RUnlock()
+		return result
+	}
+	mutex.RUnlock()
+	return nil
+}
+
+// GetAllOk returns all stored values for the request as a map and a boolean value that indicates if
+// the request was registered.
+func GetAllOk(r *http.Request) (map[interface{}]interface{}, bool) {
+	mutex.RLock()
+	context, ok := data[r]
+	result := make(map[interface{}]interface{}, len(context))
+	for k, v := range context {
+		result[k] = v
+	}
+	mutex.RUnlock()
+	return result, ok
+}
+
+// Delete removes a value stored for a given key in a given request.
+func Delete(r *http.Request, key interface{}) {
+	mutex.Lock()
+	if data[r] != nil {
+		delete(data[r], key)
+	}
+	mutex.Unlock()
+}
+
+// Clear removes all values stored for a given request.
+//
+// This is usually called by a handler wrapper to clean up request
+// variables at the end of a request lifetime. See ClearHandler().
+func Clear(r *http.Request) {
+	mutex.Lock()
+	clear(r)
+	mutex.Unlock()
+}
+
+// clear is Clear without the lock.
+func clear(r *http.Request) {
+	delete(data, r)
+	delete(datat, r)
+}
+
+// Purge removes request data stored for longer than maxAge, in seconds.
+// It returns the amount of requests removed.
+//
+// If maxAge <= 0, all request data is removed.
+//
+// This is only used for sanity check: in case context cleaning was not
+// properly set some request data can be kept forever, consuming an increasing
+// amount of memory. In case this is detected, Purge() must be called
+// periodically until the problem is fixed.
+func Purge(maxAge int) int {
+	mutex.Lock()
+	count := 0
+	if maxAge <= 0 {
+		count = len(data)
+		data = make(map[*http.Request]map[interface{}]interface{})
+		datat = make(map[*http.Request]int64)
+	} else {
+		min := time.Now().Unix() - int64(maxAge)
+		for r := range data {
+			if datat[r] < min {
+				clear(r)
+				count++
+			}
+		}
+	}
+	mutex.Unlock()
+	return count
+}
+
+// ClearHandler wraps an http.Handler and clears request values at the end
+// of a request lifetime.
+func ClearHandler(h http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		defer Clear(r)
+		h.ServeHTTP(w, r)
+	})
+}

vendor/github.com/gorilla/context/doc.go

@@ -0,0 +1,82 @@
+// Copyright 2012 The Gorilla Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+/*
+Package context stores values shared during a request lifetime.
+
+For example, a router can set variables extracted from the URL and later
+application handlers can access those values, or it can be used to store
+sessions values to be saved at the end of a request. There are several
+others common uses.
+
+The idea was posted by Brad Fitzpatrick to the go-nuts mailing list:
+
+	http://groups.google.com/group/golang-nuts/msg/e2d679d303aa5d53
+
+Here's the basic usage: first define the keys that you will need. The key
+type is interface{} so a key can be of any type that supports equality.
+Here we define a key using a custom int type to avoid name collisions:
+
+	package foo
+
+	import (
+		"github.com/gorilla/context"
+	)
+
+	type key int
+
+	const MyKey key = 0
+
+Then set a variable. Variables are bound to an http.Request object, so you
+need a request instance to set a value:
+
+	context.Set(r, MyKey, "bar")
+
+The application can later access the variable using the same key you provided:
+
+	func MyHandler(w http.ResponseWriter, r *http.Request) {
+		// val is "bar".
+		val := context.Get(r, foo.MyKey)
+
+		// returns ("bar", true)
+		val, ok := context.GetOk(r, foo.MyKey)
+		// ...
+	}
+
+And that's all about the basic usage. We discuss some other ideas below.
+
+Any type can be stored in the context. To enforce a given type, make the key
+private and wrap Get() and Set() to accept and return values of a specific
+type:
+
+	type key int
+
+	const mykey key = 0
+
+	// GetMyKey returns a value for this package from the request values.
+	func GetMyKey(r *http.Request) SomeType {
+		if rv := context.Get(r, mykey); rv != nil {
+			return rv.(SomeType)
+		}
+		return nil
+	}
+
+	// SetMyKey sets a value for this package in the request values.
+	func SetMyKey(r *http.Request, val SomeType) {
+		context.Set(r, mykey, val)
+	}
+
+Variables must be cleared at the end of a request, to remove all values
+that were stored. This can be done in an http.Handler, after a request was
+served. Just call Clear() passing the request:
+
+	context.Clear(r)
+
+...or use ClearHandler(), which conveniently wraps an http.Handler to clear
+variables at the end of a request lifetime.
+
+The Routers from the packages gorilla/mux and gorilla/pat call Clear()
+so if you are using either of them you don't need to clear the context manually.
+*/
+package context

vendor/github.com/gorilla/handlers/.travis.yml

@@ -0,0 +1,17 @@
+language: go
+sudo: false
+
+matrix:
+  include:
+    - go: 1.4
+    - go: 1.5
+    - go: 1.6
+    - go: tip
+  allow_failures:
+    - go: tip
+
+script:
+  - go get -t -v ./...
+  - diff -u <(echo -n) <(gofmt -d .)
+  - go vet $(go list ./... | grep -v /vendor/)
+  - go test -v -race ./...

vendor/github.com/gorilla/handlers/LICENSE

@@ -0,0 +1,22 @@
+Copyright (c) 2013 The Gorilla Handlers Authors. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+  Redistributions of source code must retain the above copyright notice, this
+  list of conditions and the following disclaimer.
+
+  Redistributions in binary form must reproduce the above copyright notice,
+  this list of conditions and the following disclaimer in the documentation
+  and/or other materials provided with the distribution.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

vendor/github.com/gorilla/handlers/README.md

@@ -0,0 +1,53 @@
+gorilla/handlers
+================
+[![GoDoc](https://godoc.org/github.com/gorilla/handlers?status.svg)](https://godoc.org/github.com/gorilla/handlers) [![Build Status](https://travis-ci.org/gorilla/handlers.svg?branch=master)](https://travis-ci.org/gorilla/handlers)
+
+Package handlers is a collection of handlers (aka "HTTP middleware") for use
+with Go's `net/http` package (or any framework supporting `http.Handler`), including:
+
+* [**LoggingHandler**](https://godoc.org/github.com/gorilla/handlers#LoggingHandler) for logging HTTP requests in the Apache [Common Log
+  Format](http://httpd.apache.org/docs/2.2/logs.html#common).
+* [**CombinedLoggingHandler**](https://godoc.org/github.com/gorilla/handlers#CombinedLoggingHandler) for logging HTTP requests in the Apache [Combined Log
+  Format](http://httpd.apache.org/docs/2.2/logs.html#combined) commonly used by
+  both Apache and nginx.
+* [**CompressHandler**](https://godoc.org/github.com/gorilla/handlers#CompressHandler) for gzipping responses.
+* [**ContentTypeHandler**](https://godoc.org/github.com/gorilla/handlers#ContentTypeHandler) for validating requests against a list of accepted
+  content types.
+* [**MethodHandler**](https://godoc.org/github.com/gorilla/handlers#MethodHandler) for matching HTTP methods against handlers in a
+  `map[string]http.Handler`
+* [**ProxyHeaders**](https://godoc.org/github.com/gorilla/handlers#ProxyHeaders) for populating `r.RemoteAddr` and `r.URL.Scheme` based on the
+  `X-Forwarded-For`, `X-Real-IP`, `X-Forwarded-Proto` and RFC7239 `Forwarded`
+  headers when running a Go server behind a HTTP reverse proxy.
+* [**CanonicalHost**](https://godoc.org/github.com/gorilla/handlers#CanonicalHost) for re-directing to the preferred host when handling multiple 
+  domains (i.e. multiple CNAME aliases).
+* [**RecoveryHandler**](https://godoc.org/github.com/gorilla/handlers#RecoveryHandler) for recovering from unexpected panics.
+
+Other handlers are documented [on the Gorilla
+website](http://www.gorillatoolkit.org/pkg/handlers).
+
+## Example
+
+A simple example using `handlers.LoggingHandler` and `handlers.CompressHandler`:
+
+```go
+import (
+    "net/http"
+    "github.com/gorilla/handlers"
+)
+
+func main() {
+    r := http.NewServeMux()
+
+    // Only log requests to our admin dashboard to stdout
+    r.Handle("/admin", handlers.LoggingHandler(os.Stdout, http.HandlerFunc(ShowAdminDashboard)))
+    r.HandleFunc("/", ShowIndex)
+
+    // Wrap our server with our gzip handler to gzip compress all responses.
+    http.ListenAndServe(":8000", handlers.CompressHandler(r))
+}
+```
+
+## License
+
+BSD licensed. See the included LICENSE file for details.
+

vendor/github.com/gorilla/handlers/canonical.go

@@ -0,0 +1,74 @@
+package handlers
+
+import (
+	"net/http"
+	"net/url"
+	"strings"
+)
+
+type canonical struct {
+	h      http.Handler
+	domain string
+	code   int
+}
+
+// CanonicalHost is HTTP middleware that re-directs requests to the canonical
+// domain. It accepts a domain and a status code (e.g. 301 or 302) and
+// re-directs clients to this domain. The existing request path is maintained.
+//
+// Note: If the provided domain is considered invalid by url.Parse or otherwise
+// returns an empty scheme or host, clients are not re-directed.
+//
+// Example:
+//
+//  r := mux.NewRouter()
+//  canonical := handlers.CanonicalHost("http://www.gorillatoolkit.org", 302)
+//  r.HandleFunc("/route", YourHandler)
+//
+//  log.Fatal(http.ListenAndServe(":7000", canonical(r)))
+//
+func CanonicalHost(domain string, code int) func(h http.Handler) http.Handler {
+	fn := func(h http.Handler) http.Handler {
+		return canonical{h, domain, code}
+	}
+
+	return fn
+}
+
+func (c canonical) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	dest, err := url.Parse(c.domain)
+	if err != nil {
+		// Call the next handler if the provided domain fails to parse.
+		c.h.ServeHTTP(w, r)
+		return
+	}
+
+	if dest.Scheme == "" || dest.Host == "" {
+		// Call the next handler if the scheme or host are empty.
+		// Note that url.Parse won't fail on in this case.
+		c.h.ServeHTTP(w, r)
+		return
+	}
+
+	if !strings.EqualFold(cleanHost(r.Host), dest.Host) {
+		// Re-build the destination URL
+		dest := dest.Scheme + "://" + dest.Host + r.URL.Path
+		if r.URL.RawQuery != "" {
+			dest += "?" + r.URL.RawQuery
+		}
+		http.Redirect(w, r, dest, c.code)
+		return
+	}
+
+	c.h.ServeHTTP(w, r)
+}
+
+// cleanHost cleans invalid Host headers by stripping anything after '/' or ' '.
+// This is backported from Go 1.5 (in response to issue #11206) and attempts to
+// mitigate malformed Host headers that do not match the format in RFC7230.
+func cleanHost(in string) string {
+	if i := strings.IndexAny(in, " /"); i != -1 {
+		return in[:i]
+	}
+	return in
+}

vendor/github.com/gorilla/handlers/compress.go

@@ -0,0 +1,145 @@
+// Copyright 2013 The Gorilla Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package handlers
+
+import (
+	"compress/flate"
+	"compress/gzip"
+	"io"
+	"net/http"
+	"strings"
+)
+
+type compressResponseWriter struct {
+	io.Writer
+	http.ResponseWriter
+	http.Hijacker
+	http.Flusher
+	http.CloseNotifier
+}
+
+func (w *compressResponseWriter) WriteHeader(c int) {
+	w.ResponseWriter.Header().Del("Content-Length")
+	w.ResponseWriter.WriteHeader(c)
+}
+
+func (w *compressResponseWriter) Header() http.Header {
+	return w.ResponseWriter.Header()
+}
+
+func (w *compressResponseWriter) Write(b []byte) (int, error) {
+	h := w.ResponseWriter.Header()
+	if h.Get("Content-Type") == "" {
+		h.Set("Content-Type", http.DetectContentType(b))
+	}
+	h.Del("Content-Length")
+
+	return w.Writer.Write(b)
+}
+
+type flusher interface {
+	Flush() error
+}
+
+func (w *compressResponseWriter) Flush() {
+	// Flush compressed data if compressor supports it.
+	if f, ok := w.Writer.(flusher); ok {
+		f.Flush()
+	}
+	// Flush HTTP response.
+	if w.Flusher != nil {
+		w.Flusher.Flush()
+	}
+}
+
+// CompressHandler gzip compresses HTTP responses for clients that support it
+// via the 'Accept-Encoding' header.
+func CompressHandler(h http.Handler) http.Handler {
+	return CompressHandlerLevel(h, gzip.DefaultCompression)
+}
+
+// CompressHandlerLevel gzip compresses HTTP responses with specified compression level
+// for clients that support it via the 'Accept-Encoding' header.
+//
+// The compression level should be gzip.DefaultCompression, gzip.NoCompression,
+// or any integer value between gzip.BestSpeed and gzip.BestCompression inclusive.
+// gzip.DefaultCompression is used in case of invalid compression level.
+func CompressHandlerLevel(h http.Handler, level int) http.Handler {
+	if level < gzip.DefaultCompression || level > gzip.BestCompression {
+		level = gzip.DefaultCompression
+	}
+
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+	L:
+		for _, enc := range strings.Split(r.Header.Get("Accept-Encoding"), ",") {
+			switch strings.TrimSpace(enc) {
+			case "gzip":
+				w.Header().Set("Content-Encoding", "gzip")
+				w.Header().Add("Vary", "Accept-Encoding")
+
+				gw, _ := gzip.NewWriterLevel(w, level)
+				defer gw.Close()
+
+				h, hok := w.(http.Hijacker)
+				if !hok { /* w is not Hijacker... oh well... */
+					h = nil
+				}
+
+				f, fok := w.(http.Flusher)
+				if !fok {
+					f = nil
+				}
+
+				cn, cnok := w.(http.CloseNotifier)
+				if !cnok {
+					cn = nil
+				}
+
+				w = &compressResponseWriter{
+					Writer:         gw,
+					ResponseWriter: w,
+					Hijacker:       h,
+					Flusher:        f,
+					CloseNotifier:  cn,
+				}
+
+				break L
+			case "deflate":
+				w.Header().Set("Content-Encoding", "deflate")
+				w.Header().Add("Vary", "Accept-Encoding")
+
+				fw, _ := flate.NewWriter(w, level)
+				defer fw.Close()
+
+				h, hok := w.(http.Hijacker)
+				if !hok { /* w is not Hijacker... oh well... */
+					h = nil
+				}
+
+				f, fok := w.(http.Flusher)
+				if !fok {
+					f = nil
+				}
+
+				cn, cnok := w.(http.CloseNotifier)
+				if !cnok {
+					cn = nil
+				}
+
+				w = &compressResponseWriter{
+					Writer:         fw,
+					ResponseWriter: w,
+					Hijacker:       h,
+					Flusher:        f,
+					CloseNotifier:  cn,
+				}
+
+				break L
+			}
+		}
+
+		h.ServeHTTP(w, r)
+	})
+}

vendor/github.com/gorilla/handlers/cors.go

@@ -0,0 +1,317 @@
+package handlers
+
+import (
+	"net/http"
+	"strconv"
+	"strings"
+)
+
+// CORSOption represents a functional option for configuring the CORS middleware.
+type CORSOption func(*cors) error
+
+type cors struct {
+	h                      http.Handler
+	allowedHeaders         []string
+	allowedMethods         []string
+	allowedOrigins         []string
+	allowedOriginValidator OriginValidator
+	exposedHeaders         []string
+	maxAge                 int
+	ignoreOptions          bool
+	allowCredentials       bool
+}
+
+// OriginValidator takes an origin string and returns whether or not that origin is allowed.
+type OriginValidator func(string) bool
+
+var (
+	defaultCorsMethods = []string{"GET", "HEAD", "POST"}
+	defaultCorsHeaders = []string{"Accept", "Accept-Language", "Content-Language", "Origin"}
+	// (WebKit/Safari v9 sends the Origin header by default in AJAX requests)
+)
+
+const (
+	corsOptionMethod           string = "OPTIONS"
+	corsAllowOriginHeader      string = "Access-Control-Allow-Origin"
+	corsExposeHeadersHeader    string = "Access-Control-Expose-Headers"
+	corsMaxAgeHeader           string = "Access-Control-Max-Age"
+	corsAllowMethodsHeader     string = "Access-Control-Allow-Methods"
+	corsAllowHeadersHeader     string = "Access-Control-Allow-Headers"
+	corsAllowCredentialsHeader string = "Access-Control-Allow-Credentials"
+	corsRequestMethodHeader    string = "Access-Control-Request-Method"
+	corsRequestHeadersHeader   string = "Access-Control-Request-Headers"
+	corsOriginHeader           string = "Origin"
+	corsVaryHeader             string = "Vary"
+	corsOriginMatchAll         string = "*"
+)
+
+func (ch *cors) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	origin := r.Header.Get(corsOriginHeader)
+	if !ch.isOriginAllowed(origin) {
+		ch.h.ServeHTTP(w, r)
+		return
+	}
+
+	if r.Method == corsOptionMethod {
+		if ch.ignoreOptions {
+			ch.h.ServeHTTP(w, r)
+			return
+		}
+
+		if _, ok := r.Header[corsRequestMethodHeader]; !ok {
+			w.WriteHeader(http.StatusBadRequest)
+			return
+		}
+
+		method := r.Header.Get(corsRequestMethodHeader)
+		if !ch.isMatch(method, ch.allowedMethods) {
+			w.WriteHeader(http.StatusMethodNotAllowed)
+			return
+		}
+
+		requestHeaders := strings.Split(r.Header.Get(corsRequestHeadersHeader), ",")
+		allowedHeaders := []string{}
+		for _, v := range requestHeaders {
+			canonicalHeader := http.CanonicalHeaderKey(strings.TrimSpace(v))
+			if canonicalHeader == "" || ch.isMatch(canonicalHeader, defaultCorsHeaders) {
+				continue
+			}
+
+			if !ch.isMatch(canonicalHeader, ch.allowedHeaders) {
+				w.WriteHeader(http.StatusForbidden)
+				return
+			}
+
+			allowedHeaders = append(allowedHeaders, canonicalHeader)
+		}
+
+		if len(allowedHeaders) > 0 {
+			w.Header().Set(corsAllowHeadersHeader, strings.Join(allowedHeaders, ","))
+		}
+
+		if ch.maxAge > 0 {
+			w.Header().Set(corsMaxAgeHeader, strconv.Itoa(ch.maxAge))
+		}
+
+		if !ch.isMatch(method, defaultCorsMethods) {
+			w.Header().Set(corsAllowMethodsHeader, method)
+		}
+	} else {
+		if len(ch.exposedHeaders) > 0 {
+			w.Header().Set(corsExposeHeadersHeader, strings.Join(ch.exposedHeaders, ","))
+		}
+	}
+
+	if ch.allowCredentials {
+		w.Header().Set(corsAllowCredentialsHeader, "true")
+	}
+
+	if len(ch.allowedOrigins) > 1 {
+		w.Header().Set(corsVaryHeader, corsOriginHeader)
+	}
+
+	w.Header().Set(corsAllowOriginHeader, origin)
+
+	if r.Method == corsOptionMethod {
+		return
+	}
+	ch.h.ServeHTTP(w, r)
+}
+
+// CORS provides Cross-Origin Resource Sharing middleware.
+// Example:
+//
+//  import (
+//      "net/http"
+//
+//      "github.com/gorilla/handlers"
+//      "github.com/gorilla/mux"
+//  )
+//
+//  func main() {
+//      r := mux.NewRouter()
+//      r.HandleFunc("/users", UserEndpoint)
+//      r.HandleFunc("/projects", ProjectEndpoint)
+//
+//      // Apply the CORS middleware to our top-level router, with the defaults.
+//      http.ListenAndServe(":8000", handlers.CORS()(r))
+//  }
+//
+func CORS(opts ...CORSOption) func(http.Handler) http.Handler {
+	return func(h http.Handler) http.Handler {
+		ch := parseCORSOptions(opts...)
+		ch.h = h
+		return ch
+	}
+}
+
+func parseCORSOptions(opts ...CORSOption) *cors {
+	ch := &cors{
+		allowedMethods: defaultCorsMethods,
+		allowedHeaders: defaultCorsHeaders,
+		allowedOrigins: []string{corsOriginMatchAll},
+	}
+
+	for _, option := range opts {
+		option(ch)
+	}
+
+	return ch
+}
+
+//
+// Functional options for configuring CORS.
+//
+
+// AllowedHeaders adds the provided headers to the list of allowed headers in a
+// CORS request.
+// This is an append operation so the headers Accept, Accept-Language,
+// and Content-Language are always allowed.
+// Content-Type must be explicitly declared if accepting Content-Types other than
+// application/x-www-form-urlencoded, multipart/form-data, or text/plain.
+func AllowedHeaders(headers []string) CORSOption {
+	return func(ch *cors) error {
+		for _, v := range headers {
+			normalizedHeader := http.CanonicalHeaderKey(strings.TrimSpace(v))
+			if normalizedHeader == "" {
+				continue
+			}
+
+			if !ch.isMatch(normalizedHeader, ch.allowedHeaders) {
+				ch.allowedHeaders = append(ch.allowedHeaders, normalizedHeader)
+			}
+		}
+
+		return nil
+	}
+}
+
+// AllowedMethods can be used to explicitly allow methods in the
+// Access-Control-Allow-Methods header.
+// This is a replacement operation so you must also
+// pass GET, HEAD, and POST if you wish to support those methods.
+func AllowedMethods(methods []string) CORSOption {
+	return func(ch *cors) error {
+		ch.allowedMethods = []string{}
+		for _, v := range methods {
+			normalizedMethod := strings.ToUpper(strings.TrimSpace(v))
+			if normalizedMethod == "" {
+				continue
+			}
+
+			if !ch.isMatch(normalizedMethod, ch.allowedMethods) {
+				ch.allowedMethods = append(ch.allowedMethods, normalizedMethod)
+			}
+		}
+
+		return nil
+	}
+}
+
+// AllowedOrigins sets the allowed origins for CORS requests, as used in the
+// 'Allow-Access-Control-Origin' HTTP header.
+// Note: Passing in a []string{"*"} will allow any domain.
+func AllowedOrigins(origins []string) CORSOption {
+	return func(ch *cors) error {
+		for _, v := range origins {
+			if v == corsOriginMatchAll {
+				ch.allowedOrigins = []string{corsOriginMatchAll}
+				return nil
+			}
+		}
+
+		ch.allowedOrigins = origins
+		return nil
+	}
+}
+
+// AllowedOriginValidator sets a function for evaluating allowed origins in CORS requests, represented by the
+// 'Allow-Access-Control-Origin' HTTP header.
+func AllowedOriginValidator(fn OriginValidator) CORSOption {
+	return func(ch *cors) error {
+		ch.allowedOriginValidator = fn
+		return nil
+	}
+}
+
+// ExposeHeaders can be used to specify headers that are available
+// and will not be stripped out by the user-agent.
+func ExposedHeaders(headers []string) CORSOption {
+	return func(ch *cors) error {
+		ch.exposedHeaders = []string{}
+		for _, v := range headers {
+			normalizedHeader := http.CanonicalHeaderKey(strings.TrimSpace(v))
+			if normalizedHeader == "" {
+				continue
+			}
+
+			if !ch.isMatch(normalizedHeader, ch.exposedHeaders) {
+				ch.exposedHeaders = append(ch.exposedHeaders, normalizedHeader)
+			}
+		}
+
+		return nil
+	}
+}
+
+// MaxAge determines the maximum age (in seconds) between preflight requests. A
+// maximum of 10 minutes is allowed. An age above this value will default to 10
+// minutes.
+func MaxAge(age int) CORSOption {
+	return func(ch *cors) error {
+		// Maximum of 10 minutes.
+		if age > 600 {
+			age = 600
+		}
+
+		ch.maxAge = age
+		return nil
+	}
+}
+
+// IgnoreOptions causes the CORS middleware to ignore OPTIONS requests, instead
+// passing them through to the next handler. This is useful when your application
+// or framework has a pre-existing mechanism for responding to OPTIONS requests.
+func IgnoreOptions() CORSOption {
+	return func(ch *cors) error {
+		ch.ignoreOptions = true
+		return nil
+	}
+}
+
+// AllowCredentials can be used to specify that the user agent may pass
+// authentication details along with the request.
+func AllowCredentials() CORSOption {
+	return func(ch *cors) error {
+		ch.allowCredentials = true
+		return nil
+	}
+}
+
+func (ch *cors) isOriginAllowed(origin string) bool {
+	if origin == "" {
+		return false
+	}
+
+	if ch.allowedOriginValidator != nil {
+		return ch.allowedOriginValidator(origin)
+	}
+
+	for _, allowedOrigin := range ch.allowedOrigins {
+		if allowedOrigin == origin || allowedOrigin == corsOriginMatchAll {
+			return true
+		}
+	}
+
+	return false
+}
+
+func (ch *cors) isMatch(needle string, haystack []string) bool {
+	for _, v := range haystack {
+		if v == needle {
+			return true
+		}
+	}
+
+	return false
+}

vendor/github.com/gorilla/handlers/doc.go

@@ -0,0 +1,9 @@
+/*
+Package handlers is a collection of handlers (aka "HTTP middleware") for use
+with Go's net/http package (or any framework supporting http.Handler).
+
+The package includes handlers for logging in standardised formats, compressing
+HTTP responses, validating content types and other useful tools for manipulating
+requests and responses.
+*/
+package handlers

vendor/github.com/gorilla/handlers/handlers.go

@@ -0,0 +1,403 @@
+// Copyright 2013 The Gorilla Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package handlers
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"net"
+	"net/http"
+	"net/url"
+	"sort"
+	"strconv"
+	"strings"
+	"time"
+	"unicode/utf8"
+)
+
+// MethodHandler is an http.Handler that dispatches to a handler whose key in the
+// MethodHandler's map matches the name of the HTTP request's method, eg: GET
+//
+// If the request's method is OPTIONS and OPTIONS is not a key in the map then
+// the handler responds with a status of 200 and sets the Allow header to a
+// comma-separated list of available methods.
+//
+// If the request's method doesn't match any of its keys the handler responds
+// with a status of HTTP 405 "Method Not Allowed" and sets the Allow header to a
+// comma-separated list of available methods.
+type MethodHandler map[string]http.Handler
+
+func (h MethodHandler) ServeHTTP(w http.ResponseWriter, req *http.Request) {
+	if handler, ok := h[req.Method]; ok {
+		handler.ServeHTTP(w, req)
+	} else {
+		allow := []string{}
+		for k := range h {
+			allow = append(allow, k)
+		}
+		sort.Strings(allow)
+		w.Header().Set("Allow", strings.Join(allow, ", "))
+		if req.Method == "OPTIONS" {
+			w.WriteHeader(http.StatusOK)
+		} else {
+			http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
+		}
+	}
+}
+
+// loggingHandler is the http.Handler implementation for LoggingHandlerTo and its
+// friends
+type loggingHandler struct {
+	writer  io.Writer
+	handler http.Handler
+}
+
+// combinedLoggingHandler is the http.Handler implementation for LoggingHandlerTo
+// and its friends
+type combinedLoggingHandler struct {
+	writer  io.Writer
+	handler http.Handler
+}
+
+func (h loggingHandler) ServeHTTP(w http.ResponseWriter, req *http.Request) {
+	t := time.Now()
+	logger := makeLogger(w)
+	url := *req.URL
+	h.handler.ServeHTTP(logger, req)
+	writeLog(h.writer, req, url, t, logger.Status(), logger.Size())
+}
+
+func (h combinedLoggingHandler) ServeHTTP(w http.ResponseWriter, req *http.Request) {
+	t := time.Now()
+	logger := makeLogger(w)
+	url := *req.URL
+	h.handler.ServeHTTP(logger, req)
+	writeCombinedLog(h.writer, req, url, t, logger.Status(), logger.Size())
+}
+
+func makeLogger(w http.ResponseWriter) loggingResponseWriter {
+	var logger loggingResponseWriter = &responseLogger{w: w}
+	if _, ok := w.(http.Hijacker); ok {
+		logger = &hijackLogger{responseLogger{w: w}}
+	}
+	h, ok1 := logger.(http.Hijacker)
+	c, ok2 := w.(http.CloseNotifier)
+	if ok1 && ok2 {
+		return hijackCloseNotifier{logger, h, c}
+	}
+	if ok2 {
+		return &closeNotifyWriter{logger, c}
+	}
+	return logger
+}
+
+type loggingResponseWriter interface {
+	http.ResponseWriter
+	http.Flusher
+	Status() int
+	Size() int
+}
+
+// responseLogger is wrapper of http.ResponseWriter that keeps track of its HTTP
+// status code and body size
+type responseLogger struct {
+	w      http.ResponseWriter
+	status int
+	size   int
+}
+
+func (l *responseLogger) Header() http.Header {
+	return l.w.Header()
+}
+
+func (l *responseLogger) Write(b []byte) (int, error) {
+	if l.status == 0 {
+		// The status will be StatusOK if WriteHeader has not been called yet
+		l.status = http.StatusOK
+	}
+	size, err := l.w.Write(b)
+	l.size += size
+	return size, err
+}
+
+func (l *responseLogger) WriteHeader(s int) {
+	l.w.WriteHeader(s)
+	l.status = s
+}
+
+func (l *responseLogger) Status() int {
+	return l.status
+}
+
+func (l *responseLogger) Size() int {
+	return l.size
+}
+
+func (l *responseLogger) Flush() {
+	f, ok := l.w.(http.Flusher)
+	if ok {
+		f.Flush()
+	}
+}
+
+type hijackLogger struct {
+	responseLogger
+}
+
+func (l *hijackLogger) Hijack() (net.Conn, *bufio.ReadWriter, error) {
+	h := l.responseLogger.w.(http.Hijacker)
+	conn, rw, err := h.Hijack()
+	if err == nil && l.responseLogger.status == 0 {
+		// The status will be StatusSwitchingProtocols if there was no error and
+		// WriteHeader has not been called yet
+		l.responseLogger.status = http.StatusSwitchingProtocols
+	}
+	return conn, rw, err
+}
+
+type closeNotifyWriter struct {
+	loggingResponseWriter
+	http.CloseNotifier
+}
+
+type hijackCloseNotifier struct {
+	loggingResponseWriter
+	http.Hijacker
+	http.CloseNotifier
+}
+
+const lowerhex = "0123456789abcdef"
+
+func appendQuoted(buf []byte, s string) []byte {
+	var runeTmp [utf8.UTFMax]byte
+	for width := 0; len(s) > 0; s = s[width:] {
+		r := rune(s[0])
+		width = 1
+		if r >= utf8.RuneSelf {
+			r, width = utf8.DecodeRuneInString(s)
+		}
+		if width == 1 && r == utf8.RuneError {
+			buf = append(buf, `\x`...)
+			buf = append(buf, lowerhex[s[0]>>4])
+			buf = append(buf, lowerhex[s[0]&0xF])
+			continue
+		}
+		if r == rune('"') || r == '\\' { // always backslashed
+			buf = append(buf, '\\')
+			buf = append(buf, byte(r))
+			continue
+		}
+		if strconv.IsPrint(r) {
+			n := utf8.EncodeRune(runeTmp[:], r)
+			buf = append(buf, runeTmp[:n]...)
+			continue
+		}
+		switch r {
+		case '\a':
+			buf = append(buf, `\a`...)
+		case '\b':
+			buf = append(buf, `\b`...)
+		case '\f':
+			buf = append(buf, `\f`...)
+		case '\n':
+			buf = append(buf, `\n`...)
+		case '\r':
+			buf = append(buf, `\r`...)
+		case '\t':
+			buf = append(buf, `\t`...)
+		case '\v':
+			buf = append(buf, `\v`...)
+		default:
+			switch {
+			case r < ' ':
+				buf = append(buf, `\x`...)
+				buf = append(buf, lowerhex[s[0]>>4])
+				buf = append(buf, lowerhex[s[0]&0xF])
+			case r > utf8.MaxRune:
+				r = 0xFFFD
+				fallthrough
+			case r < 0x10000:
+				buf = append(buf, `\u`...)
+				for s := 12; s >= 0; s -= 4 {
+					buf = append(buf, lowerhex[r>>uint(s)&0xF])
+				}
+			default:
+				buf = append(buf, `\U`...)
+				for s := 28; s >= 0; s -= 4 {
+					buf = append(buf, lowerhex[r>>uint(s)&0xF])
+				}
+			}
+		}
+	}
+	return buf
+
+}
+
+// buildCommonLogLine builds a log entry for req in Apache Common Log Format.
+// ts is the timestamp with which the entry should be logged.
+// status and size are used to provide the response HTTP status and size.
+func buildCommonLogLine(req *http.Request, url url.URL, ts time.Time, status int, size int) []byte {
+	username := "-"
+	if url.User != nil {
+		if name := url.User.Username(); name != "" {
+			username = name
+		}
+	}
+
+	host, _, err := net.SplitHostPort(req.RemoteAddr)
+
+	if err != nil {
+		host = req.RemoteAddr
+	}
+
+	uri := req.RequestURI
+
+	// Requests using the CONNECT method over HTTP/2.0 must use
+	// the authority field (aka r.Host) to identify the target.
+	// Refer: https://httpwg.github.io/specs/rfc7540.html#CONNECT
+	if req.ProtoMajor == 2 && req.Method == "CONNECT" {
+		uri = req.Host
+	}
+	if uri == "" {
+		uri = url.RequestURI()
+	}
+
+	buf := make([]byte, 0, 3*(len(host)+len(username)+len(req.Method)+len(uri)+len(req.Proto)+50)/2)
+	buf = append(buf, host...)
+	buf = append(buf, " - "...)
+	buf = append(buf, username...)
+	buf = append(buf, " ["...)
+	buf = append(buf, ts.Format("02/Jan/2006:15:04:05 -0700")...)
+	buf = append(buf, `] "`...)
+	buf = append(buf, req.Method...)
+	buf = append(buf, " "...)
+	buf = appendQuoted(buf, uri)
+	buf = append(buf, " "...)
+	buf = append(buf, req.Proto...)
+	buf = append(buf, `" `...)
+	buf = append(buf, strconv.Itoa(status)...)
+	buf = append(buf, " "...)
+	buf = append(buf, strconv.Itoa(size)...)
+	return buf
+}
+
+// writeLog writes a log entry for req to w in Apache Common Log Format.
+// ts is the timestamp with which the entry should be logged.
+// status and size are used to provide the response HTTP status and size.
+func writeLog(w io.Writer, req *http.Request, url url.URL, ts time.Time, status, size int) {
+	buf := buildCommonLogLine(req, url, ts, status, size)
+	buf = append(buf, '\n')
+	w.Write(buf)
+}
+
+// writeCombinedLog writes a log entry for req to w in Apache Combined Log Format.
+// ts is the timestamp with which the entry should be logged.
+// status and size are used to provide the response HTTP status and size.
+func writeCombinedLog(w io.Writer, req *http.Request, url url.URL, ts time.Time, status, size int) {
+	buf := buildCommonLogLine(req, url, ts, status, size)
+	buf = append(buf, ` "`...)
+	buf = appendQuoted(buf, req.Referer())
+	buf = append(buf, `" "`...)
+	buf = appendQuoted(buf, req.UserAgent())
+	buf = append(buf, '"', '\n')
+	w.Write(buf)
+}
+
+// CombinedLoggingHandler return a http.Handler that wraps h and logs requests to out in
+// Apache Combined Log Format.
+//
+// See http://httpd.apache.org/docs/2.2/logs.html#combined for a description of this format.
+//
+// LoggingHandler always sets the ident field of the log to -
+func CombinedLoggingHandler(out io.Writer, h http.Handler) http.Handler {
+	return combinedLoggingHandler{out, h}
+}
+
+// LoggingHandler return a http.Handler that wraps h and logs requests to out in
+// Apache Common Log Format (CLF).
+//
+// See http://httpd.apache.org/docs/2.2/logs.html#common for a description of this format.
+//
+// LoggingHandler always sets the ident field of the log to -
+//
+// Example:
+//
+//  r := mux.NewRouter()
+//  r.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
+//  	w.Write([]byte("This is a catch-all route"))
+//  })
+//  loggedRouter := handlers.LoggingHandler(os.Stdout, r)
+//  http.ListenAndServe(":1123", loggedRouter)
+//
+func LoggingHandler(out io.Writer, h http.Handler) http.Handler {
+	return loggingHandler{out, h}
+}
+
+// isContentType validates the Content-Type header matches the supplied
+// contentType. That is, its type and subtype match.
+func isContentType(h http.Header, contentType string) bool {
+	ct := h.Get("Content-Type")
+	if i := strings.IndexRune(ct, ';'); i != -1 {
+		ct = ct[0:i]
+	}
+	return ct == contentType
+}
+
+// ContentTypeHandler wraps and returns a http.Handler, validating the request
+// content type is compatible with the contentTypes list. It writes a HTTP 415
+// error if that fails.
+//
+// Only PUT, POST, and PATCH requests are considered.
+func ContentTypeHandler(h http.Handler, contentTypes ...string) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if !(r.Method == "PUT" || r.Method == "POST" || r.Method == "PATCH") {
+			h.ServeHTTP(w, r)
+			return
+		}
+
+		for _, ct := range contentTypes {
+			if isContentType(r.Header, ct) {
+				h.ServeHTTP(w, r)
+				return
+			}
+		}
+		http.Error(w, fmt.Sprintf("Unsupported content type %q; expected one of %q", r.Header.Get("Content-Type"), contentTypes), http.StatusUnsupportedMediaType)
+	})
+}
+
+const (
+	// HTTPMethodOverrideHeader is a commonly used
+	// http header to override a request method.
+	HTTPMethodOverrideHeader = "X-HTTP-Method-Override"
+	// HTTPMethodOverrideFormKey is a commonly used
+	// HTML form key to override a request method.
+	HTTPMethodOverrideFormKey = "_method"
+)
+
+// HTTPMethodOverrideHandler wraps and returns a http.Handler which checks for
+// the X-HTTP-Method-Override header or the _method form key, and overrides (if
+// valid) request.Method with its value.
+//
+// This is especially useful for HTTP clients that don't support many http verbs.
+// It isn't secure to override e.g a GET to a POST, so only POST requests are
+// considered.  Likewise, the override method can only be a "write" method: PUT,
+// PATCH or DELETE.
+//
+// Form method takes precedence over header method.
+func HTTPMethodOverrideHandler(h http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.Method == "POST" {
+			om := r.FormValue(HTTPMethodOverrideFormKey)
+			if om == "" {
+				om = r.Header.Get(HTTPMethodOverrideHeader)
+			}
+			if om == "PUT" || om == "PATCH" || om == "DELETE" {
+				r.Method = om
+			}
+		}
+		h.ServeHTTP(w, r)
+	})
+}

vendor/github.com/gorilla/handlers/proxy_headers.go

@@ -0,0 +1,113 @@
+package handlers
+
+import (
+	"net/http"
+	"regexp"
+	"strings"
+)
+
+var (
+	// De-facto standard header keys.
+	xForwardedFor   = http.CanonicalHeaderKey("X-Forwarded-For")
+	xRealIP         = http.CanonicalHeaderKey("X-Real-IP")
+	xForwardedProto = http.CanonicalHeaderKey("X-Forwarded-Scheme")
+)
+
+var (
+	// RFC7239 defines a new "Forwarded: " header designed to replace the
+	// existing use of X-Forwarded-* headers.
+	// e.g. Forwarded: for=192.0.2.60;proto=https;by=203.0.113.43
+	forwarded = http.CanonicalHeaderKey("Forwarded")
+	// Allows for a sub-match of the first value after 'for=' to the next
+	// comma, semi-colon or space. The match is case-insensitive.
+	forRegex = regexp.MustCompile(`(?i)(?:for=)([^(;|,| )]+)`)
+	// Allows for a sub-match for the first instance of scheme (http|https)
+	// prefixed by 'proto='. The match is case-insensitive.
+	protoRegex = regexp.MustCompile(`(?i)(?:proto=)(https|http)`)
+)
+
+// ProxyHeaders inspects common reverse proxy headers and sets the corresponding
+// fields in the HTTP request struct. These are X-Forwarded-For and X-Real-IP
+// for the remote (client) IP address, X-Forwarded-Proto for the scheme
+// (http|https) and the RFC7239 Forwarded header, which may include both client
+// IPs and schemes.
+//
+// NOTE: This middleware should only be used when behind a reverse
+// proxy like nginx, HAProxy or Apache. Reverse proxies that don't (or are
+// configured not to) strip these headers from client requests, or where these
+// headers are accepted "as is" from a remote client (e.g. when Go is not behind
+// a proxy), can manifest as a vulnerability if your application uses these
+// headers for validating the 'trustworthiness' of a request.
+func ProxyHeaders(h http.Handler) http.Handler {
+	fn := func(w http.ResponseWriter, r *http.Request) {
+		// Set the remote IP with the value passed from the proxy.
+		if fwd := getIP(r); fwd != "" {
+			r.RemoteAddr = fwd
+		}
+
+		// Set the scheme (proto) with the value passed from the proxy.
+		if scheme := getScheme(r); scheme != "" {
+			r.URL.Scheme = scheme
+		}
+
+		// Call the next handler in the chain.
+		h.ServeHTTP(w, r)
+	}
+
+	return http.HandlerFunc(fn)
+}
+
+// getIP retrieves the IP from the X-Forwarded-For, X-Real-IP and RFC7239
+// Forwarded headers (in that order).
+func getIP(r *http.Request) string {
+	var addr string
+
+	if fwd := r.Header.Get(xForwardedFor); fwd != "" {
+		// Only grab the first (client) address. Note that '192.168.0.1,
+		// 10.1.1.1' is a valid key for X-Forwarded-For where addresses after
+		// the first may represent forwarding proxies earlier in the chain.
+		s := strings.Index(fwd, ", ")
+		if s == -1 {
+			s = len(fwd)
+		}
+		addr = fwd[:s]
+	} else if fwd := r.Header.Get(xRealIP); fwd != "" {
+		// X-Real-IP should only contain one IP address (the client making the
+		// request).
+		addr = fwd
+	} else if fwd := r.Header.Get(forwarded); fwd != "" {
+		// match should contain at least two elements if the protocol was
+		// specified in the Forwarded header. The first element will always be
+		// the 'for=' capture, which we ignore. In the case of multiple IP
+		// addresses (for=8.8.8.8, 8.8.4.4,172.16.1.20 is valid) we only
+		// extract the first, which should be the client IP.
+		if match := forRegex.FindStringSubmatch(fwd); len(match) > 1 {
+			// IPv6 addresses in Forwarded headers are quoted-strings. We strip
+			// these quotes.
+			addr = strings.Trim(match[1], `"`)
+		}
+	}
+
+	return addr
+}
+
+// getScheme retrieves the scheme from the X-Forwarded-Proto and RFC7239
+// Forwarded headers (in that order).
+func getScheme(r *http.Request) string {
+	var scheme string
+
+	// Retrieve the scheme from X-Forwarded-Proto.
+	if proto := r.Header.Get(xForwardedProto); proto != "" {
+		scheme = strings.ToLower(proto)
+	} else if proto := r.Header.Get(forwarded); proto != "" {
+		// match should contain at least two elements if the protocol was
+		// specified in the Forwarded header. The first element will always be
+		// the 'proto=' capture, which we ignore. In the case of multiple proto
+		// parameters (invalid) we only extract the first.
+		if match := protoRegex.FindStringSubmatch(proto); len(match) > 1 {
+			scheme = strings.ToLower(match[1])
+		}
+	}
+
+	return scheme
+}

vendor/github.com/gorilla/handlers/recovery.go

@@ -0,0 +1,86 @@
+package handlers
+
+import (
+	"log"
+	"net/http"
+	"runtime/debug"
+)
+
+type recoveryHandler struct {
+	handler    http.Handler
+	logger     *log.Logger
+	printStack bool
+}
+
+// RecoveryOption provides a functional approach to define
+// configuration for a handler; such as setting the logging
+// whether or not to print strack traces on panic.
+type RecoveryOption func(http.Handler)
+
+func parseRecoveryOptions(h http.Handler, opts ...RecoveryOption) http.Handler {
+	for _, option := range opts {
+		option(h)
+	}
+
+	return h
+}
+
+// RecoveryHandler is HTTP middleware that recovers from a panic,
+// logs the panic, writes http.StatusInternalServerError, and
+// continues to the next handler.
+//
+// Example:
+//
+//  r := mux.NewRouter()
+//  r.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
+//  	panic("Unexpected error!")
+//  })
+//
+//  http.ListenAndServe(":1123", handlers.RecoveryHandler()(r))
+func RecoveryHandler(opts ...RecoveryOption) func(h http.Handler) http.Handler {
+	return func(h http.Handler) http.Handler {
+		r := &recoveryHandler{handler: h}
+		return parseRecoveryOptions(r, opts...)
+	}
+}
+
+// RecoveryLogger is a functional option to override
+// the default logger
+func RecoveryLogger(logger *log.Logger) RecoveryOption {
+	return func(h http.Handler) {
+		r := h.(*recoveryHandler)
+		r.logger = logger
+	}
+}
+
+// PrintRecoveryStack is a functional option to enable
+// or disable printing stack traces on panic.
+func PrintRecoveryStack(print bool) RecoveryOption {
+	return func(h http.Handler) {
+		r := h.(*recoveryHandler)
+		r.printStack = print
+	}
+}
+
+func (h recoveryHandler) ServeHTTP(w http.ResponseWriter, req *http.Request) {
+	defer func() {
+		if err := recover(); err != nil {
+			w.WriteHeader(http.StatusInternalServerError)
+			h.log(err)
+		}
+	}()
+
+	h.handler.ServeHTTP(w, req)
+}
+
+func (h recoveryHandler) log(message interface{}) {
+	if h.logger != nil {
+		h.logger.Println(message)
+	} else {
+		log.Println(message)
+	}
+
+	if h.printStack {
+		debug.PrintStack()
+	}
+}

vendor/github.com/gorilla/mux/.travis.yml

@@ -0,0 +1,17 @@
+language: go
+sudo: false
+
+matrix:
+  include:
+    - go: 1.2
+    - go: 1.3
+    - go: 1.4
+    - go: 1.5
+    - go: 1.6
+    - go: tip
+
+script:
+  - go get -t -v ./...
+  - diff -u <(echo -n) <(gofmt -d .)
+  - go tool vet .
+  - go test -v -race ./...

vendor/github.com/gorilla/mux/LICENSE

@@ -0,0 +1,27 @@
+Copyright (c) 2012 Rodrigo Moraes. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+	 * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+	 * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+	 * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

vendor/github.com/gorilla/mux/README.md

@@ -0,0 +1,242 @@
+mux
+===
+[![GoDoc](https://godoc.org/github.com/gorilla/mux?status.svg)](https://godoc.org/github.com/gorilla/mux)
+[![Build Status](https://travis-ci.org/gorilla/mux.svg?branch=master)](https://travis-ci.org/gorilla/mux)
+
+http://www.gorillatoolkit.org/pkg/mux
+
+Package `gorilla/mux` implements a request router and dispatcher.
+
+The name mux stands for "HTTP request multiplexer". Like the standard `http.ServeMux`, `mux.Router` matches incoming requests against a list of registered routes and calls a handler for the route that matches the URL or other conditions. The main features are:
+
+* Requests can be matched based on URL host, path, path prefix, schemes, header and query values, HTTP methods or using custom matchers.
+* URL hosts and paths can have variables with an optional regular expression.
+* Registered URLs can be built, or "reversed", which helps maintaining references to resources.
+* Routes can be used as subrouters: nested routes are only tested if the parent route matches. This is useful to define groups of routes that share common conditions like a host, a path prefix or other repeated attributes. As a bonus, this optimizes request matching.
+* It implements the `http.Handler` interface so it is compatible with the standard `http.ServeMux`.
+
+Let's start registering a couple of URL paths and handlers:
+
+```go
+func main() {
+	r := mux.NewRouter()
+	r.HandleFunc("/", HomeHandler)
+	r.HandleFunc("/products", ProductsHandler)
+	r.HandleFunc("/articles", ArticlesHandler)
+	http.Handle("/", r)
+}
+```
+
+Here we register three routes mapping URL paths to handlers. This is equivalent to how `http.HandleFunc()` works: if an incoming request URL matches one of the paths, the corresponding handler is called passing (`http.ResponseWriter`, `*http.Request`) as parameters.
+
+Paths can have variables. They are defined using the format `{name}` or `{name:pattern}`. If a regular expression pattern is not defined, the matched variable will be anything until the next slash. For example:
+
+```go
+r := mux.NewRouter()
+r.HandleFunc("/products/{key}", ProductHandler)
+r.HandleFunc("/articles/{category}/", ArticlesCategoryHandler)
+r.HandleFunc("/articles/{category}/{id:[0-9]+}", ArticleHandler)
+```
+
+The names are used to create a map of route variables which can be retrieved calling `mux.Vars()`:
+
+```go
+vars := mux.Vars(request)
+category := vars["category"]
+```
+
+And this is all you need to know about the basic usage. More advanced options are explained below.
+
+Routes can also be restricted to a domain or subdomain. Just define a host pattern to be matched. They can also have variables:
+
+```go
+r := mux.NewRouter()
+// Only matches if domain is "www.example.com".
+r.Host("www.example.com")
+// Matches a dynamic subdomain.
+r.Host("{subdomain:[a-z]+}.domain.com")
+```
+
+There are several other matchers that can be added. To match path prefixes:
+
+```go
+r.PathPrefix("/products/")
+```
+
+...or HTTP methods:
+
+```go
+r.Methods("GET", "POST")
+```
+
+...or URL schemes:
+
+```go
+r.Schemes("https")
+```
+
+...or header values:
+
+```go
+r.Headers("X-Requested-With", "XMLHttpRequest")
+```
+
+...or query values:
+
+```go
+r.Queries("key", "value")
+```
+
+...or to use a custom matcher function:
+
+```go
+r.MatcherFunc(func(r *http.Request, rm *RouteMatch) bool {
+	return r.ProtoMajor == 0
+})
+```
+
+...and finally, it is possible to combine several matchers in a single route:
+
+```go
+r.HandleFunc("/products", ProductsHandler).
+  Host("www.example.com").
+  Methods("GET").
+  Schemes("http")
+```
+
+Setting the same matching conditions again and again can be boring, so we have a way to group several routes that share the same requirements. We call it "subrouting".
+
+For example, let's say we have several URLs that should only match when the host is `www.example.com`. Create a route for that host and get a "subrouter" from it:
+
+```go
+r := mux.NewRouter()
+s := r.Host("www.example.com").Subrouter()
+```
+
+Then register routes in the subrouter:
+
+```go
+s.HandleFunc("/products/", ProductsHandler)
+s.HandleFunc("/products/{key}", ProductHandler)
+s.HandleFunc("/articles/{category}/{id:[0-9]+}"), ArticleHandler)
+```
+
+The three URL paths we registered above will only be tested if the domain is `www.example.com`, because the subrouter is tested first. This is not only convenient, but also optimizes request matching. You can create subrouters combining any attribute matchers accepted by a route.
+
+Subrouters can be used to create domain or path "namespaces": you define subrouters in a central place and then parts of the app can register its paths relatively to a given subrouter.
+
+There's one more thing about subroutes. When a subrouter has a path prefix, the inner routes use it as base for their paths:
+
+```go
+r := mux.NewRouter()
+s := r.PathPrefix("/products").Subrouter()
+// "/products/"
+s.HandleFunc("/", ProductsHandler)
+// "/products/{key}/"
+s.HandleFunc("/{key}/", ProductHandler)
+// "/products/{key}/details"
+s.HandleFunc("/{key}/details", ProductDetailsHandler)
+```
+
+Now let's see how to build registered URLs.
+
+Routes can be named. All routes that define a name can have their URLs built, or "reversed". We define a name calling `Name()` on a route. For example:
+
+```go
+r := mux.NewRouter()
+r.HandleFunc("/articles/{category}/{id:[0-9]+}", ArticleHandler).
+  Name("article")
+```
+
+To build a URL, get the route and call the `URL()` method, passing a sequence of key/value pairs for the route variables. For the previous route, we would do:
+
+```go
+url, err := r.Get("article").URL("category", "technology", "id", "42")
+```
+
+...and the result will be a `url.URL` with the following path:
+
+```
+"/articles/technology/42"
+```
+
+This also works for host variables:
+
+```go
+r := mux.NewRouter()
+r.Host("{subdomain}.domain.com").
+  Path("/articles/{category}/{id:[0-9]+}").
+  HandlerFunc(ArticleHandler).
+  Name("article")
+
+// url.String() will be "http://news.domain.com/articles/technology/42"
+url, err := r.Get("article").URL("subdomain", "news",
+                                 "category", "technology",
+                                 "id", "42")
+```
+
+All variables defined in the route are required, and their values must conform to the corresponding patterns. These requirements guarantee that a generated URL will always match a registered route -- the only exception is for explicitly defined "build-only" routes which never match.
+
+Regex support also exists for matching Headers within a route. For example, we could do:
+
+```go
+r.HeadersRegexp("Content-Type", "application/(text|json)")
+```
+
+...and the route will match both requests with a Content-Type of `application/json` as well as `application/text`
+
+There's also a way to build only the URL host or path for a route: use the methods `URLHost()` or `URLPath()` instead. For the previous route, we would do:
+
+```go
+// "http://news.domain.com/"
+host, err := r.Get("article").URLHost("subdomain", "news")
+
+// "/articles/technology/42"
+path, err := r.Get("article").URLPath("category", "technology", "id", "42")
+```
+
+And if you use subrouters, host and path defined separately can be built as well:
+
+```go
+r := mux.NewRouter()
+s := r.Host("{subdomain}.domain.com").Subrouter()
+s.Path("/articles/{category}/{id:[0-9]+}").
+  HandlerFunc(ArticleHandler).
+  Name("article")
+
+// "http://news.domain.com/articles/technology/42"
+url, err := r.Get("article").URL("subdomain", "news",
+                                 "category", "technology",
+                                 "id", "42")
+```
+
+## Full Example
+
+Here's a complete, runnable example of a small `mux` based server:
+
+```go
+package main
+
+import (
+	"net/http"
+
+	"github.com/gorilla/mux"
+)
+
+func YourHandler(w http.ResponseWriter, r *http.Request) {
+	w.Write([]byte("Gorilla!\n"))
+}
+
+func main() {
+	r := mux.NewRouter()
+	// Routes consist of a path and a handler function.
+	r.HandleFunc("/", YourHandler)
+
+	// Bind to a port and pass our router in
+	http.ListenAndServe(":8000", r)
+}
+```
+
+## License
+
+BSD licensed. See the LICENSE file for details.

vendor/github.com/gorilla/mux/doc.go

@@ -0,0 +1,206 @@
+// Copyright 2012 The Gorilla Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+/*
+Package mux implements a request router and dispatcher.
+
+The name mux stands for "HTTP request multiplexer". Like the standard
+http.ServeMux, mux.Router matches incoming requests against a list of
+registered routes and calls a handler for the route that matches the URL
+or other conditions. The main features are:
+
+	* Requests can be matched based on URL host, path, path prefix, schemes,
+	  header and query values, HTTP methods or using custom matchers.
+	* URL hosts and paths can have variables with an optional regular
+	  expression.
+	* Registered URLs can be built, or "reversed", which helps maintaining
+	  references to resources.
+	* Routes can be used as subrouters: nested routes are only tested if the
+	  parent route matches. This is useful to define groups of routes that
+	  share common conditions like a host, a path prefix or other repeated
+	  attributes. As a bonus, this optimizes request matching.
+	* It implements the http.Handler interface so it is compatible with the
+	  standard http.ServeMux.
+
+Let's start registering a couple of URL paths and handlers:
+
+	func main() {
+		r := mux.NewRouter()
+		r.HandleFunc("/", HomeHandler)
+		r.HandleFunc("/products", ProductsHandler)
+		r.HandleFunc("/articles", ArticlesHandler)
+		http.Handle("/", r)
+	}
+
+Here we register three routes mapping URL paths to handlers. This is
+equivalent to how http.HandleFunc() works: if an incoming request URL matches
+one of the paths, the corresponding handler is called passing
+(http.ResponseWriter, *http.Request) as parameters.
+
+Paths can have variables. They are defined using the format {name} or
+{name:pattern}. If a regular expression pattern is not defined, the matched
+variable will be anything until the next slash. For example:
+
+	r := mux.NewRouter()
+	r.HandleFunc("/products/{key}", ProductHandler)
+	r.HandleFunc("/articles/{category}/", ArticlesCategoryHandler)
+	r.HandleFunc("/articles/{category}/{id:[0-9]+}", ArticleHandler)
+
+The names are used to create a map of route variables which can be retrieved
+calling mux.Vars():
+
+	vars := mux.Vars(request)
+	category := vars["category"]
+
+And this is all you need to know about the basic usage. More advanced options
+are explained below.
+
+Routes can also be restricted to a domain or subdomain. Just define a host
+pattern to be matched. They can also have variables:
+
+	r := mux.NewRouter()
+	// Only matches if domain is "www.example.com".
+	r.Host("www.example.com")
+	// Matches a dynamic subdomain.
+	r.Host("{subdomain:[a-z]+}.domain.com")
+
+There are several other matchers that can be added. To match path prefixes:
+
+	r.PathPrefix("/products/")
+
+...or HTTP methods:
+
+	r.Methods("GET", "POST")
+
+...or URL schemes:
+
+	r.Schemes("https")
+
+...or header values:
+
+	r.Headers("X-Requested-With", "XMLHttpRequest")
+
+...or query values:
+
+	r.Queries("key", "value")
+
+...or to use a custom matcher function:
+
+	r.MatcherFunc(func(r *http.Request, rm *RouteMatch) bool {
+		return r.ProtoMajor == 0
+	})
+
+...and finally, it is possible to combine several matchers in a single route:
+
+	r.HandleFunc("/products", ProductsHandler).
+	  Host("www.example.com").
+	  Methods("GET").
+	  Schemes("http")
+
+Setting the same matching conditions again and again can be boring, so we have
+a way to group several routes that share the same requirements.
+We call it "subrouting".
+
+For example, let's say we have several URLs that should only match when the
+host is "www.example.com". Create a route for that host and get a "subrouter"
+from it:
+
+	r := mux.NewRouter()
+	s := r.Host("www.example.com").Subrouter()
+
+Then register routes in the subrouter:
+
+	s.HandleFunc("/products/", ProductsHandler)
+	s.HandleFunc("/products/{key}", ProductHandler)
+	s.HandleFunc("/articles/{category}/{id:[0-9]+}"), ArticleHandler)
+
+The three URL paths we registered above will only be tested if the domain is
+"www.example.com", because the subrouter is tested first. This is not
+only convenient, but also optimizes request matching. You can create
+subrouters combining any attribute matchers accepted by a route.
+
+Subrouters can be used to create domain or path "namespaces": you define
+subrouters in a central place and then parts of the app can register its
+paths relatively to a given subrouter.
+
+There's one more thing about subroutes. When a subrouter has a path prefix,
+the inner routes use it as base for their paths:
+
+	r := mux.NewRouter()
+	s := r.PathPrefix("/products").Subrouter()
+	// "/products/"
+	s.HandleFunc("/", ProductsHandler)
+	// "/products/{key}/"
+	s.HandleFunc("/{key}/", ProductHandler)
+	// "/products/{key}/details"
+	s.HandleFunc("/{key}/details", ProductDetailsHandler)
+
+Now let's see how to build registered URLs.
+
+Routes can be named. All routes that define a name can have their URLs built,
+or "reversed". We define a name calling Name() on a route. For example:
+
+	r := mux.NewRouter()
+	r.HandleFunc("/articles/{category}/{id:[0-9]+}", ArticleHandler).
+	  Name("article")
+
+To build a URL, get the route and call the URL() method, passing a sequence of
+key/value pairs for the route variables. For the previous route, we would do:
+
+	url, err := r.Get("article").URL("category", "technology", "id", "42")
+
+...and the result will be a url.URL with the following path:
+
+	"/articles/technology/42"
+
+This also works for host variables:
+
+	r := mux.NewRouter()
+	r.Host("{subdomain}.domain.com").
+	  Path("/articles/{category}/{id:[0-9]+}").
+	  HandlerFunc(ArticleHandler).
+	  Name("article")
+
+	// url.String() will be "http://news.domain.com/articles/technology/42"
+	url, err := r.Get("article").URL("subdomain", "news",
+	                                 "category", "technology",
+	                                 "id", "42")
+
+All variables defined in the route are required, and their values must
+conform to the corresponding patterns. These requirements guarantee that a
+generated URL will always match a registered route -- the only exception is
+for explicitly defined "build-only" routes which never match.
+
+Regex support also exists for matching Headers within a route. For example, we could do:
+
+	r.HeadersRegexp("Content-Type", "application/(text|json)")
+
+...and the route will match both requests with a Content-Type of `application/json` as well as
+`application/text`
+
+There's also a way to build only the URL host or path for a route:
+use the methods URLHost() or URLPath() instead. For the previous route,
+we would do:
+
+	// "http://news.domain.com/"
+	host, err := r.Get("article").URLHost("subdomain", "news")
+
+	// "/articles/technology/42"
+	path, err := r.Get("article").URLPath("category", "technology", "id", "42")
+
+And if you use subrouters, host and path defined separately can be built
+as well:
+
+	r := mux.NewRouter()
+	s := r.Host("{subdomain}.domain.com").Subrouter()
+	s.Path("/articles/{category}/{id:[0-9]+}").
+	  HandlerFunc(ArticleHandler).
+	  Name("article")
+
+	// "http://news.domain.com/articles/technology/42"
+	url, err := r.Get("article").URL("subdomain", "news",
+	                                 "category", "technology",
+	                                 "id", "42")
+*/
+package mux

vendor/github.com/gorilla/mux/mux.go

@@ -0,0 +1,499 @@
+// Copyright 2012 The Gorilla Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package mux
+
+import (
+	"errors"
+	"fmt"
+	"net/http"
+	"path"
+	"regexp"
+
+	"github.com/gorilla/context"
+)
+
+// NewRouter returns a new router instance.
+func NewRouter() *Router {
+	return &Router{namedRoutes: make(map[string]*Route), KeepContext: false}
+}
+
+// Router registers routes to be matched and dispatches a handler.
+//
+// It implements the http.Handler interface, so it can be registered to serve
+// requests:
+//
+//     var router = mux.NewRouter()
+//
+//     func main() {
+//         http.Handle("/", router)
+//     }
+//
+// Or, for Google App Engine, register it in a init() function:
+//
+//     func init() {
+//         http.Handle("/", router)
+//     }
+//
+// This will send all incoming requests to the router.
+type Router struct {
+	// Configurable Handler to be used when no route matches.
+	NotFoundHandler http.Handler
+	// Parent route, if this is a subrouter.
+	parent parentRoute
+	// Routes to be matched, in order.
+	routes []*Route
+	// Routes by name for URL building.
+	namedRoutes map[string]*Route
+	// See Router.StrictSlash(). This defines the flag for new routes.
+	strictSlash bool
+	// See Router.SkipClean(). This defines the flag for new routes.
+	skipClean bool
+	// If true, do not clear the request context after handling the request
+	KeepContext bool
+}
+
+// Match matches registered routes against the request.
+func (r *Router) Match(req *http.Request, match *RouteMatch) bool {
+	for _, route := range r.routes {
+		if route.Match(req, match) {
+			return true
+		}
+	}
+
+	// Closest match for a router (includes sub-routers)
+	if r.NotFoundHandler != nil {
+		match.Handler = r.NotFoundHandler
+		return true
+	}
+	return false
+}
+
+// ServeHTTP dispatches the handler registered in the matched route.
+//
+// When there is a match, the route variables can be retrieved calling
+// mux.Vars(request).
+func (r *Router) ServeHTTP(w http.ResponseWriter, req *http.Request) {
+	if !r.skipClean {
+		// Clean path to canonical form and redirect.
+		if p := cleanPath(req.URL.Path); p != req.URL.Path {
+
+			// Added 3 lines (Philip Schlump) - It was dropping the query string and #whatever from query.
+			// This matches with fix in go 1.2 r.c. 4 for same problem.  Go Issue:
+			// http://code.google.com/p/go/issues/detail?id=5252
+			url := *req.URL
+			url.Path = p
+			p = url.String()
+
+			w.Header().Set("Location", p)
+			w.WriteHeader(http.StatusMovedPermanently)
+			return
+		}
+	}
+	var match RouteMatch
+	var handler http.Handler
+	if r.Match(req, &match) {
+		handler = match.Handler
+		setVars(req, match.Vars)
+		setCurrentRoute(req, match.Route)
+	}
+	if handler == nil {
+		handler = http.NotFoundHandler()
+	}
+	if !r.KeepContext {
+		defer context.Clear(req)
+	}
+	handler.ServeHTTP(w, req)
+}
+
+// Get returns a route registered with the given name.
+func (r *Router) Get(name string) *Route {
+	return r.getNamedRoutes()[name]
+}
+
+// GetRoute returns a route registered with the given name. This method
+// was renamed to Get() and remains here for backwards compatibility.
+func (r *Router) GetRoute(name string) *Route {
+	return r.getNamedRoutes()[name]
+}
+
+// StrictSlash defines the trailing slash behavior for new routes. The initial
+// value is false.
+//
+// When true, if the route path is "/path/", accessing "/path" will redirect
+// to the former and vice versa. In other words, your application will always
+// see the path as specified in the route.
+//
+// When false, if the route path is "/path", accessing "/path/" will not match
+// this route and vice versa.
+//
+// Special case: when a route sets a path prefix using the PathPrefix() method,
+// strict slash is ignored for that route because the redirect behavior can't
+// be determined from a prefix alone. However, any subrouters created from that
+// route inherit the original StrictSlash setting.
+func (r *Router) StrictSlash(value bool) *Router {
+	r.strictSlash = value
+	return r
+}
+
+// SkipClean defines the path cleaning behaviour for new routes. The initial
+// value is false. Users should be careful about which routes are not cleaned
+//
+// When true, if the route path is "/path//to", it will remain with the double
+// slash. This is helpful if you have a route like: /fetch/http://xkcd.com/534/
+//
+// When false, the path will be cleaned, so /fetch/http://xkcd.com/534/ will
+// become /fetch/http/xkcd.com/534
+func (r *Router) SkipClean(value bool) *Router {
+	r.skipClean = value
+	return r
+}
+
+// ----------------------------------------------------------------------------
+// parentRoute
+// ----------------------------------------------------------------------------
+
+// getNamedRoutes returns the map where named routes are registered.
+func (r *Router) getNamedRoutes() map[string]*Route {
+	if r.namedRoutes == nil {
+		if r.parent != nil {
+			r.namedRoutes = r.parent.getNamedRoutes()
+		} else {
+			r.namedRoutes = make(map[string]*Route)
+		}
+	}
+	return r.namedRoutes
+}
+
+// getRegexpGroup returns regexp definitions from the parent route, if any.
+func (r *Router) getRegexpGroup() *routeRegexpGroup {
+	if r.parent != nil {
+		return r.parent.getRegexpGroup()
+	}
+	return nil
+}
+
+func (r *Router) buildVars(m map[string]string) map[string]string {
+	if r.parent != nil {
+		m = r.parent.buildVars(m)
+	}
+	return m
+}
+
+// ----------------------------------------------------------------------------
+// Route factories
+// ----------------------------------------------------------------------------
+
+// NewRoute registers an empty route.
+func (r *Router) NewRoute() *Route {
+	route := &Route{parent: r, strictSlash: r.strictSlash, skipClean: r.skipClean}
+	r.routes = append(r.routes, route)
+	return route
+}
+
+// Handle registers a new route with a matcher for the URL path.
+// See Route.Path() and Route.Handler().
+func (r *Router) Handle(path string, handler http.Handler) *Route {
+	return r.NewRoute().Path(path).Handler(handler)
+}
+
+// HandleFunc registers a new route with a matcher for the URL path.
+// See Route.Path() and Route.HandlerFunc().
+func (r *Router) HandleFunc(path string, f func(http.ResponseWriter,
+	*http.Request)) *Route {
+	return r.NewRoute().Path(path).HandlerFunc(f)
+}
+
+// Headers registers a new route with a matcher for request header values.
+// See Route.Headers().
+func (r *Router) Headers(pairs ...string) *Route {
+	return r.NewRoute().Headers(pairs...)
+}
+
+// Host registers a new route with a matcher for the URL host.
+// See Route.Host().
+func (r *Router) Host(tpl string) *Route {
+	return r.NewRoute().Host(tpl)
+}
+
+// MatcherFunc registers a new route with a custom matcher function.
+// See Route.MatcherFunc().
+func (r *Router) MatcherFunc(f MatcherFunc) *Route {
+	return r.NewRoute().MatcherFunc(f)
+}
+
+// Methods registers a new route with a matcher for HTTP methods.
+// See Route.Methods().
+func (r *Router) Methods(methods ...string) *Route {
+	return r.NewRoute().Methods(methods...)
+}
+
+// Path registers a new route with a matcher for the URL path.
+// See Route.Path().
+func (r *Router) Path(tpl string) *Route {
+	return r.NewRoute().Path(tpl)
+}
+
+// PathPrefix registers a new route with a matcher for the URL path prefix.
+// See Route.PathPrefix().
+func (r *Router) PathPrefix(tpl string) *Route {
+	return r.NewRoute().PathPrefix(tpl)
+}
+
+// Queries registers a new route with a matcher for URL query values.
+// See Route.Queries().
+func (r *Router) Queries(pairs ...string) *Route {
+	return r.NewRoute().Queries(pairs...)
+}
+
+// Schemes registers a new route with a matcher for URL schemes.
+// See Route.Schemes().
+func (r *Router) Schemes(schemes ...string) *Route {
+	return r.NewRoute().Schemes(schemes...)
+}
+
+// BuildVarsFunc registers a new route with a custom function for modifying
+// route variables before building a URL.
+func (r *Router) BuildVarsFunc(f BuildVarsFunc) *Route {
+	return r.NewRoute().BuildVarsFunc(f)
+}
+
+// Walk walks the router and all its sub-routers, calling walkFn for each route
+// in the tree. The routes are walked in the order they were added. Sub-routers
+// are explored depth-first.
+func (r *Router) Walk(walkFn WalkFunc) error {
+	return r.walk(walkFn, []*Route{})
+}
+
+// SkipRouter is used as a return value from WalkFuncs to indicate that the
+// router that walk is about to descend down to should be skipped.
+var SkipRouter = errors.New("skip this router")
+
+// WalkFunc is the type of the function called for each route visited by Walk.
+// At every invocation, it is given the current route, and the current router,
+// and a list of ancestor routes that lead to the current route.
+type WalkFunc func(route *Route, router *Router, ancestors []*Route) error
+
+func (r *Router) walk(walkFn WalkFunc, ancestors []*Route) error {
+	for _, t := range r.routes {
+		if t.regexp == nil || t.regexp.path == nil || t.regexp.path.template == "" {
+			continue
+		}
+
+		err := walkFn(t, r, ancestors)
+		if err == SkipRouter {
+			continue
+		}
+		for _, sr := range t.matchers {
+			if h, ok := sr.(*Router); ok {
+				err := h.walk(walkFn, ancestors)
+				if err != nil {
+					return err
+				}
+			}
+		}
+		if h, ok := t.handler.(*Router); ok {
+			ancestors = append(ancestors, t)
+			err := h.walk(walkFn, ancestors)
+			if err != nil {
+				return err
+			}
+			ancestors = ancestors[:len(ancestors)-1]
+		}
+	}
+	return nil
+}
+
+// ----------------------------------------------------------------------------
+// Context
+// ----------------------------------------------------------------------------
+
+// RouteMatch stores information about a matched route.
+type RouteMatch struct {
+	Route   *Route
+	Handler http.Handler
+	Vars    map[string]string
+}
+
+type contextKey int
+
+const (
+	varsKey contextKey = iota
+	routeKey
+)
+
+// Vars returns the route variables for the current request, if any.
+func Vars(r *http.Request) map[string]string {
+	if rv := context.Get(r, varsKey); rv != nil {
+		return rv.(map[string]string)
+	}
+	return nil
+}
+
+// CurrentRoute returns the matched route for the current request, if any.
+// This only works when called inside the handler of the matched route
+// because the matched route is stored in the request context which is cleared
+// after the handler returns, unless the KeepContext option is set on the
+// Router.
+func CurrentRoute(r *http.Request) *Route {
+	if rv := context.Get(r, routeKey); rv != nil {
+		return rv.(*Route)
+	}
+	return nil
+}
+
+func setVars(r *http.Request, val interface{}) {
+	if val != nil {
+		context.Set(r, varsKey, val)
+	}
+}
+
+func setCurrentRoute(r *http.Request, val interface{}) {
+	if val != nil {
+		context.Set(r, routeKey, val)
+	}
+}
+
+// ----------------------------------------------------------------------------
+// Helpers
+// ----------------------------------------------------------------------------
+
+// cleanPath returns the canonical path for p, eliminating . and .. elements.
+// Borrowed from the net/http package.
+func cleanPath(p string) string {
+	if p == "" {
+		return "/"
+	}
+	if p[0] != '/' {
+		p = "/" + p
+	}
+	np := path.Clean(p)
+	// path.Clean removes trailing slash except for root;
+	// put the trailing slash back if necessary.
+	if p[len(p)-1] == '/' && np != "/" {
+		np += "/"
+	}
+
+	return np
+}
+
+// uniqueVars returns an error if two slices contain duplicated strings.
+func uniqueVars(s1, s2 []string) error {
+	for _, v1 := range s1 {
+		for _, v2 := range s2 {
+			if v1 == v2 {
+				return fmt.Errorf("mux: duplicated route variable %q", v2)
+			}
+		}
+	}
+	return nil
+}
+
+// checkPairs returns the count of strings passed in, and an error if
+// the count is not an even number.
+func checkPairs(pairs ...string) (int, error) {
+	length := len(pairs)
+	if length%2 != 0 {
+		return length, fmt.Errorf(
+			"mux: number of parameters must be multiple of 2, got %v", pairs)
+	}
+	return length, nil
+}
+
+// mapFromPairsToString converts variadic string parameters to a
+// string to string map.
+func mapFromPairsToString(pairs ...string) (map[string]string, error) {
+	length, err := checkPairs(pairs...)
+	if err != nil {
+		return nil, err
+	}
+	m := make(map[string]string, length/2)
+	for i := 0; i < length; i += 2 {
+		m[pairs[i]] = pairs[i+1]
+	}
+	return m, nil
+}
+
+// mapFromPairsToRegex converts variadic string paramers to a
+// string to regex map.
+func mapFromPairsToRegex(pairs ...string) (map[string]*regexp.Regexp, error) {
+	length, err := checkPairs(pairs...)
+	if err != nil {
+		return nil, err
+	}
+	m := make(map[string]*regexp.Regexp, length/2)
+	for i := 0; i < length; i += 2 {
+		regex, err := regexp.Compile(pairs[i+1])
+		if err != nil {
+			return nil, err
+		}
+		m[pairs[i]] = regex
+	}
+	return m, nil
+}
+
+// matchInArray returns true if the given string value is in the array.
+func matchInArray(arr []string, value string) bool {
+	for _, v := range arr {
+		if v == value {
+			return true
+		}
+	}
+	return false
+}
+
+// matchMapWithString returns true if the given key/value pairs exist in a given map.
+func matchMapWithString(toCheck map[string]string, toMatch map[string][]string, canonicalKey bool) bool {
+	for k, v := range toCheck {
+		// Check if key exists.
+		if canonicalKey {
+			k = http.CanonicalHeaderKey(k)
+		}
+		if values := toMatch[k]; values == nil {
+			return false
+		} else if v != "" {
+			// If value was defined as an empty string we only check that the
+			// key exists. Otherwise we also check for equality.
+			valueExists := false
+			for _, value := range values {
+				if v == value {
+					valueExists = true
+					break
+				}
+			}
+			if !valueExists {
+				return false
+			}
+		}
+	}
+	return true
+}
+
+// matchMapWithRegex returns true if the given key/value pairs exist in a given map compiled against
+// the given regex
+func matchMapWithRegex(toCheck map[string]*regexp.Regexp, toMatch map[string][]string, canonicalKey bool) bool {
+	for k, v := range toCheck {
+		// Check if key exists.
+		if canonicalKey {
+			k = http.CanonicalHeaderKey(k)
+		}
+		if values := toMatch[k]; values == nil {
+			return false
+		} else if v != nil {
+			// If value was defined as an empty string we only check that the
+			// key exists. Otherwise we also check for equality.
+			valueExists := false
+			for _, value := range values {
+				if v.MatchString(value) {
+					valueExists = true
+					break
+				}
+			}
+			if !valueExists {
+				return false
+			}
+		}
+	}
+	return true
+}

vendor/github.com/gorilla/mux/regexp.go

@@ -0,0 +1,312 @@
+// Copyright 2012 The Gorilla Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package mux
+
+import (
+	"bytes"
+	"fmt"
+	"net/http"
+	"net/url"
+	"regexp"
+	"strconv"
+	"strings"
+)
+
+// newRouteRegexp parses a route template and returns a routeRegexp,
+// used to match a host, a path or a query string.
+//
+// It will extract named variables, assemble a regexp to be matched, create
+// a "reverse" template to build URLs and compile regexps to validate variable
+// values used in URL building.
+//
+// Previously we accepted only Python-like identifiers for variable
+// names ([a-zA-Z_][a-zA-Z0-9_]*), but currently the only restriction is that
+// name and pattern can't be empty, and names can't contain a colon.
+func newRouteRegexp(tpl string, matchHost, matchPrefix, matchQuery, strictSlash bool) (*routeRegexp, error) {
+	// Check if it is well-formed.
+	idxs, errBraces := braceIndices(tpl)
+	if errBraces != nil {
+		return nil, errBraces
+	}
+	// Backup the original.
+	template := tpl
+	// Now let's parse it.
+	defaultPattern := "[^/]+"
+	if matchQuery {
+		defaultPattern = "[^?&]*"
+	} else if matchHost {
+		defaultPattern = "[^.]+"
+		matchPrefix = false
+	}
+	// Only match strict slash if not matching
+	if matchPrefix || matchHost || matchQuery {
+		strictSlash = false
+	}
+	// Set a flag for strictSlash.
+	endSlash := false
+	if strictSlash && strings.HasSuffix(tpl, "/") {
+		tpl = tpl[:len(tpl)-1]
+		endSlash = true
+	}
+	varsN := make([]string, len(idxs)/2)
+	varsR := make([]*regexp.Regexp, len(idxs)/2)
+	pattern := bytes.NewBufferString("")
+	pattern.WriteByte('^')
+	reverse := bytes.NewBufferString("")
+	var end int
+	var err error
+	for i := 0; i < len(idxs); i += 2 {
+		// Set all values we are interested in.
+		raw := tpl[end:idxs[i]]
+		end = idxs[i+1]
+		parts := strings.SplitN(tpl[idxs[i]+1:end-1], ":", 2)
+		name := parts[0]
+		patt := defaultPattern
+		if len(parts) == 2 {
+			patt = parts[1]
+		}
+		// Name or pattern can't be empty.
+		if name == "" || patt == "" {
+			return nil, fmt.Errorf("mux: missing name or pattern in %q",
+				tpl[idxs[i]:end])
+		}
+		// Build the regexp pattern.
+		fmt.Fprintf(pattern, "%s(?P<%s>%s)", regexp.QuoteMeta(raw), varGroupName(i/2), patt)
+
+		// Build the reverse template.
+		fmt.Fprintf(reverse, "%s%%s", raw)
+
+		// Append variable name and compiled pattern.
+		varsN[i/2] = name
+		varsR[i/2], err = regexp.Compile(fmt.Sprintf("^%s$", patt))
+		if err != nil {
+			return nil, err
+		}
+	}
+	// Add the remaining.
+	raw := tpl[end:]
+	pattern.WriteString(regexp.QuoteMeta(raw))
+	if strictSlash {
+		pattern.WriteString("[/]?")
+	}
+	if matchQuery {
+		// Add the default pattern if the query value is empty
+		if queryVal := strings.SplitN(template, "=", 2)[1]; queryVal == "" {
+			pattern.WriteString(defaultPattern)
+		}
+	}
+	if !matchPrefix {
+		pattern.WriteByte('$')
+	}
+	reverse.WriteString(raw)
+	if endSlash {
+		reverse.WriteByte('/')
+	}
+	// Compile full regexp.
+	reg, errCompile := regexp.Compile(pattern.String())
+	if errCompile != nil {
+		return nil, errCompile
+	}
+	// Done!
+	return &routeRegexp{
+		template:    template,
+		matchHost:   matchHost,
+		matchQuery:  matchQuery,
+		strictSlash: strictSlash,
+		regexp:      reg,
+		reverse:     reverse.String(),
+		varsN:       varsN,
+		varsR:       varsR,
+	}, nil
+}
+
+// routeRegexp stores a regexp to match a host or path and information to
+// collect and validate route variables.
+type routeRegexp struct {
+	// The unmodified template.
+	template string
+	// True for host match, false for path or query string match.
+	matchHost bool
+	// True for query string match, false for path and host match.
+	matchQuery bool
+	// The strictSlash value defined on the route, but disabled if PathPrefix was used.
+	strictSlash bool
+	// Expanded regexp.
+	regexp *regexp.Regexp
+	// Reverse template.
+	reverse string
+	// Variable names.
+	varsN []string
+	// Variable regexps (validators).
+	varsR []*regexp.Regexp
+}
+
+// Match matches the regexp against the URL host or path.
+func (r *routeRegexp) Match(req *http.Request, match *RouteMatch) bool {
+	if !r.matchHost {
+		if r.matchQuery {
+			return r.matchQueryString(req)
+		}
+
+		return r.regexp.MatchString(req.URL.Path)
+	}
+
+	return r.regexp.MatchString(getHost(req))
+}
+
+// url builds a URL part using the given values.
+func (r *routeRegexp) url(values map[string]string) (string, error) {
+	urlValues := make([]interface{}, len(r.varsN))
+	for k, v := range r.varsN {
+		value, ok := values[v]
+		if !ok {
+			return "", fmt.Errorf("mux: missing route variable %q", v)
+		}
+		urlValues[k] = value
+	}
+	rv := fmt.Sprintf(r.reverse, urlValues...)
+	if !r.regexp.MatchString(rv) {
+		// The URL is checked against the full regexp, instead of checking
+		// individual variables. This is faster but to provide a good error
+		// message, we check individual regexps if the URL doesn't match.
+		for k, v := range r.varsN {
+			if !r.varsR[k].MatchString(values[v]) {
+				return "", fmt.Errorf(
+					"mux: variable %q doesn't match, expected %q", values[v],
+					r.varsR[k].String())
+			}
+		}
+	}
+	return rv, nil
+}
+
+// getURLQuery returns a single query parameter from a request URL.
+// For a URL with foo=bar&baz=ding, we return only the relevant key
+// value pair for the routeRegexp.
+func (r *routeRegexp) getURLQuery(req *http.Request) string {
+	if !r.matchQuery {
+		return ""
+	}
+	templateKey := strings.SplitN(r.template, "=", 2)[0]
+	for key, vals := range req.URL.Query() {
+		if key == templateKey && len(vals) > 0 {
+			return key + "=" + vals[0]
+		}
+	}
+	return ""
+}
+
+func (r *routeRegexp) matchQueryString(req *http.Request) bool {
+	return r.regexp.MatchString(r.getURLQuery(req))
+}
+
+// braceIndices returns the first level curly brace indices from a string.
+// It returns an error in case of unbalanced braces.
+func braceIndices(s string) ([]int, error) {
+	var level, idx int
+	var idxs []int
+	for i := 0; i < len(s); i++ {
+		switch s[i] {
+		case '{':
+			if level++; level == 1 {
+				idx = i
+			}
+		case '}':
+			if level--; level == 0 {
+				idxs = append(idxs, idx, i+1)
+			} else if level < 0 {
+				return nil, fmt.Errorf("mux: unbalanced braces in %q", s)
+			}
+		}
+	}
+	if level != 0 {
+		return nil, fmt.Errorf("mux: unbalanced braces in %q", s)
+	}
+	return idxs, nil
+}
+
+// varGroupName builds a capturing group name for the indexed variable.
+func varGroupName(idx int) string {
+	return "v" + strconv.Itoa(idx)
+}
+
+// ----------------------------------------------------------------------------
+// routeRegexpGroup
+// ----------------------------------------------------------------------------
+
+// routeRegexpGroup groups the route matchers that carry variables.
+type routeRegexpGroup struct {
+	host    *routeRegexp
+	path    *routeRegexp
+	queries []*routeRegexp
+}
+
+// setMatch extracts the variables from the URL once a route matches.
+func (v *routeRegexpGroup) setMatch(req *http.Request, m *RouteMatch, r *Route) {
+	// Store host variables.
+	if v.host != nil {
+		host := getHost(req)
+		matches := v.host.regexp.FindStringSubmatchIndex(host)
+		if len(matches) > 0 {
+			extractVars(host, matches, v.host.varsN, m.Vars)
+		}
+	}
+	// Store path variables.
+	if v.path != nil {
+		matches := v.path.regexp.FindStringSubmatchIndex(req.URL.Path)
+		if len(matches) > 0 {
+			extractVars(req.URL.Path, matches, v.path.varsN, m.Vars)
+			// Check if we should redirect.
+			if v.path.strictSlash {
+				p1 := strings.HasSuffix(req.URL.Path, "/")
+				p2 := strings.HasSuffix(v.path.template, "/")
+				if p1 != p2 {
+					u, _ := url.Parse(req.URL.String())
+					if p1 {
+						u.Path = u.Path[:len(u.Path)-1]
+					} else {
+						u.Path += "/"
+					}
+					m.Handler = http.RedirectHandler(u.String(), 301)
+				}
+			}
+		}
+	}
+	// Store query string variables.
+	for _, q := range v.queries {
+		queryURL := q.getURLQuery(req)
+		matches := q.regexp.FindStringSubmatchIndex(queryURL)
+		if len(matches) > 0 {
+			extractVars(queryURL, matches, q.varsN, m.Vars)
+		}
+	}
+}
+
+// getHost tries its best to return the request host.
+func getHost(r *http.Request) string {
+	if r.URL.IsAbs() {
+		return r.URL.Host
+	}
+	host := r.Host
+	// Slice off any port information.
+	if i := strings.Index(host, ":"); i != -1 {
+		host = host[:i]
+	}
+	return host
+
+}
+
+func extractVars(input string, matches []int, names []string, output map[string]string) {
+	matchesCount := 0
+	prevEnd := -1
+	for i := 2; i < len(matches) && matchesCount < len(names); i += 2 {
+		if prevEnd < matches[i+1] {
+			value := input[matches[i]:matches[i+1]]
+			output[names[matchesCount]] = value
+			prevEnd = matches[i+1]
+			matchesCount++
+		}
+	}
+}

vendor/github.com/gorilla/mux/route.go

@@ -0,0 +1,634 @@
+// Copyright 2012 The Gorilla Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package mux
+
+import (
+	"errors"
+	"fmt"
+	"net/http"
+	"net/url"
+	"regexp"
+	"strings"
+)
+
+// Route stores information to match a request and build URLs.
+type Route struct {
+	// Parent where the route was registered (a Router).
+	parent parentRoute
+	// Request handler for the route.
+	handler http.Handler
+	// List of matchers.
+	matchers []matcher
+	// Manager for the variables from host and path.
+	regexp *routeRegexpGroup
+	// If true, when the path pattern is "/path/", accessing "/path" will
+	// redirect to the former and vice versa.
+	strictSlash bool
+	// If true, when the path pattern is "/path//to", accessing "/path//to"
+	// will not redirect
+	skipClean bool
+	// If true, this route never matches: it is only used to build URLs.
+	buildOnly bool
+	// The name used to build URLs.
+	name string
+	// Error resulted from building a route.
+	err error
+
+	buildVarsFunc BuildVarsFunc
+}
+
+func (r *Route) SkipClean() bool {
+	return r.skipClean
+}
+
+// Match matches the route against the request.
+func (r *Route) Match(req *http.Request, match *RouteMatch) bool {
+	if r.buildOnly || r.err != nil {
+		return false
+	}
+	// Match everything.
+	for _, m := range r.matchers {
+		if matched := m.Match(req, match); !matched {
+			return false
+		}
+	}
+	// Yay, we have a match. Let's collect some info about it.
+	if match.Route == nil {
+		match.Route = r
+	}
+	if match.Handler == nil {
+		match.Handler = r.handler
+	}
+	if match.Vars == nil {
+		match.Vars = make(map[string]string)
+	}
+	// Set variables.
+	if r.regexp != nil {
+		r.regexp.setMatch(req, match, r)
+	}
+	return true
+}
+
+// ----------------------------------------------------------------------------
+// Route attributes
+// ----------------------------------------------------------------------------
+
+// GetError returns an error resulted from building the route, if any.
+func (r *Route) GetError() error {
+	return r.err
+}
+
+// BuildOnly sets the route to never match: it is only used to build URLs.
+func (r *Route) BuildOnly() *Route {
+	r.buildOnly = true
+	return r
+}
+
+// Handler --------------------------------------------------------------------
+
+// Handler sets a handler for the route.
+func (r *Route) Handler(handler http.Handler) *Route {
+	if r.err == nil {
+		r.handler = handler
+	}
+	return r
+}
+
+// HandlerFunc sets a handler function for the route.
+func (r *Route) HandlerFunc(f func(http.ResponseWriter, *http.Request)) *Route {
+	return r.Handler(http.HandlerFunc(f))
+}
+
+// GetHandler returns the handler for the route, if any.
+func (r *Route) GetHandler() http.Handler {
+	return r.handler
+}
+
+// Name -----------------------------------------------------------------------
+
+// Name sets the name for the route, used to build URLs.
+// If the name was registered already it will be overwritten.
+func (r *Route) Name(name string) *Route {
+	if r.name != "" {
+		r.err = fmt.Errorf("mux: route already has name %q, can't set %q",
+			r.name, name)
+	}
+	if r.err == nil {
+		r.name = name
+		r.getNamedRoutes()[name] = r
+	}
+	return r
+}
+
+// GetName returns the name for the route, if any.
+func (r *Route) GetName() string {
+	return r.name
+}
+
+// ----------------------------------------------------------------------------
+// Matchers
+// ----------------------------------------------------------------------------
+
+// matcher types try to match a request.
+type matcher interface {
+	Match(*http.Request, *RouteMatch) bool
+}
+
+// addMatcher adds a matcher to the route.
+func (r *Route) addMatcher(m matcher) *Route {
+	if r.err == nil {
+		r.matchers = append(r.matchers, m)
+	}
+	return r
+}
+
+// addRegexpMatcher adds a host or path matcher and builder to a route.
+func (r *Route) addRegexpMatcher(tpl string, matchHost, matchPrefix, matchQuery bool) error {
+	if r.err != nil {
+		return r.err
+	}
+	r.regexp = r.getRegexpGroup()
+	if !matchHost && !matchQuery {
+		if len(tpl) == 0 || tpl[0] != '/' {
+			return fmt.Errorf("mux: path must start with a slash, got %q", tpl)
+		}
+		if r.regexp.path != nil {
+			tpl = strings.TrimRight(r.regexp.path.template, "/") + tpl
+		}
+	}
+	rr, err := newRouteRegexp(tpl, matchHost, matchPrefix, matchQuery, r.strictSlash)
+	if err != nil {
+		return err
+	}
+	for _, q := range r.regexp.queries {
+		if err = uniqueVars(rr.varsN, q.varsN); err != nil {
+			return err
+		}
+	}
+	if matchHost {
+		if r.regexp.path != nil {
+			if err = uniqueVars(rr.varsN, r.regexp.path.varsN); err != nil {
+				return err
+			}
+		}
+		r.regexp.host = rr
+	} else {
+		if r.regexp.host != nil {
+			if err = uniqueVars(rr.varsN, r.regexp.host.varsN); err != nil {
+				return err
+			}
+		}
+		if matchQuery {
+			r.regexp.queries = append(r.regexp.queries, rr)
+		} else {
+			r.regexp.path = rr
+		}
+	}
+	r.addMatcher(rr)
+	return nil
+}
+
+// Headers --------------------------------------------------------------------
+
+// headerMatcher matches the request against header values.
+type headerMatcher map[string]string
+
+func (m headerMatcher) Match(r *http.Request, match *RouteMatch) bool {
+	return matchMapWithString(m, r.Header, true)
+}
+
+// Headers adds a matcher for request header values.
+// It accepts a sequence of key/value pairs to be matched. For example:
+//
+//     r := mux.NewRouter()
+//     r.Headers("Content-Type", "application/json",
+//               "X-Requested-With", "XMLHttpRequest")
+//
+// The above route will only match if both request header values match.
+// If the value is an empty string, it will match any value if the key is set.
+func (r *Route) Headers(pairs ...string) *Route {
+	if r.err == nil {
+		var headers map[string]string
+		headers, r.err = mapFromPairsToString(pairs...)
+		return r.addMatcher(headerMatcher(headers))
+	}
+	return r
+}
+
+// headerRegexMatcher matches the request against the route given a regex for the header
+type headerRegexMatcher map[string]*regexp.Regexp
+
+func (m headerRegexMatcher) Match(r *http.Request, match *RouteMatch) bool {
+	return matchMapWithRegex(m, r.Header, true)
+}
+
+// HeadersRegexp accepts a sequence of key/value pairs, where the value has regex
+// support. For example:
+//
+//     r := mux.NewRouter()
+//     r.HeadersRegexp("Content-Type", "application/(text|json)",
+//               "X-Requested-With", "XMLHttpRequest")
+//
+// The above route will only match if both the request header matches both regular expressions.
+// It the value is an empty string, it will match any value if the key is set.
+func (r *Route) HeadersRegexp(pairs ...string) *Route {
+	if r.err == nil {
+		var headers map[string]*regexp.Regexp
+		headers, r.err = mapFromPairsToRegex(pairs...)
+		return r.addMatcher(headerRegexMatcher(headers))
+	}
+	return r
+}
+
+// Host -----------------------------------------------------------------------
+
+// Host adds a matcher for the URL host.
+// It accepts a template with zero or more URL variables enclosed by {}.
+// Variables can define an optional regexp pattern to be matched:
+//
+// - {name} matches anything until the next dot.
+//
+// - {name:pattern} matches the given regexp pattern.
+//
+// For example:
+//
+//     r := mux.NewRouter()
+//     r.Host("www.example.com")
+//     r.Host("{subdomain}.domain.com")
+//     r.Host("{subdomain:[a-z]+}.domain.com")
+//
+// Variable names must be unique in a given route. They can be retrieved
+// calling mux.Vars(request).
+func (r *Route) Host(tpl string) *Route {
+	r.err = r.addRegexpMatcher(tpl, true, false, false)
+	return r
+}
+
+// MatcherFunc ----------------------------------------------------------------
+
+// MatcherFunc is the function signature used by custom matchers.
+type MatcherFunc func(*http.Request, *RouteMatch) bool
+
+// Match returns the match for a given request.
+func (m MatcherFunc) Match(r *http.Request, match *RouteMatch) bool {
+	return m(r, match)
+}
+
+// MatcherFunc adds a custom function to be used as request matcher.
+func (r *Route) MatcherFunc(f MatcherFunc) *Route {
+	return r.addMatcher(f)
+}
+
+// Methods --------------------------------------------------------------------
+
+// methodMatcher matches the request against HTTP methods.
+type methodMatcher []string
+
+func (m methodMatcher) Match(r *http.Request, match *RouteMatch) bool {
+	return matchInArray(m, r.Method)
+}
+
+// Methods adds a matcher for HTTP methods.
+// It accepts a sequence of one or more methods to be matched, e.g.:
+// "GET", "POST", "PUT".
+func (r *Route) Methods(methods ...string) *Route {
+	for k, v := range methods {
+		methods[k] = strings.ToUpper(v)
+	}
+	return r.addMatcher(methodMatcher(methods))
+}
+
+// Path -----------------------------------------------------------------------
+
+// Path adds a matcher for the URL path.
+// It accepts a template with zero or more URL variables enclosed by {}. The
+// template must start with a "/".
+// Variables can define an optional regexp pattern to be matched:
+//
+// - {name} matches anything until the next slash.
+//
+// - {name:pattern} matches the given regexp pattern.
+//
+// For example:
+//
+//     r := mux.NewRouter()
+//     r.Path("/products/").Handler(ProductsHandler)
+//     r.Path("/products/{key}").Handler(ProductsHandler)
+//     r.Path("/articles/{category}/{id:[0-9]+}").
+//       Handler(ArticleHandler)
+//
+// Variable names must be unique in a given route. They can be retrieved
+// calling mux.Vars(request).
+func (r *Route) Path(tpl string) *Route {
+	r.err = r.addRegexpMatcher(tpl, false, false, false)
+	return r
+}
+
+// PathPrefix -----------------------------------------------------------------
+
+// PathPrefix adds a matcher for the URL path prefix. This matches if the given
+// template is a prefix of the full URL path. See Route.Path() for details on
+// the tpl argument.
+//
+// Note that it does not treat slashes specially ("/foobar/" will be matched by
+// the prefix "/foo") so you may want to use a trailing slash here.
+//
+// Also note that the setting of Router.StrictSlash() has no effect on routes
+// with a PathPrefix matcher.
+func (r *Route) PathPrefix(tpl string) *Route {
+	r.err = r.addRegexpMatcher(tpl, false, true, false)
+	return r
+}
+
+// Query ----------------------------------------------------------------------
+
+// Queries adds a matcher for URL query values.
+// It accepts a sequence of key/value pairs. Values may define variables.
+// For example:
+//
+//     r := mux.NewRouter()
+//     r.Queries("foo", "bar", "id", "{id:[0-9]+}")
+//
+// The above route will only match if the URL contains the defined queries
+// values, e.g.: ?foo=bar&id=42.
+//
+// It the value is an empty string, it will match any value if the key is set.
+//
+// Variables can define an optional regexp pattern to be matched:
+//
+// - {name} matches anything until the next slash.
+//
+// - {name:pattern} matches the given regexp pattern.
+func (r *Route) Queries(pairs ...string) *Route {
+	length := len(pairs)
+	if length%2 != 0 {
+		r.err = fmt.Errorf(
+			"mux: number of parameters must be multiple of 2, got %v", pairs)
+		return nil
+	}
+	for i := 0; i < length; i += 2 {
+		if r.err = r.addRegexpMatcher(pairs[i]+"="+pairs[i+1], false, false, true); r.err != nil {
+			return r
+		}
+	}
+
+	return r
+}
+
+// Schemes --------------------------------------------------------------------
+
+// schemeMatcher matches the request against URL schemes.
+type schemeMatcher []string
+
+func (m schemeMatcher) Match(r *http.Request, match *RouteMatch) bool {
+	return matchInArray(m, r.URL.Scheme)
+}
+
+// Schemes adds a matcher for URL schemes.
+// It accepts a sequence of schemes to be matched, e.g.: "http", "https".
+func (r *Route) Schemes(schemes ...string) *Route {
+	for k, v := range schemes {
+		schemes[k] = strings.ToLower(v)
+	}
+	return r.addMatcher(schemeMatcher(schemes))
+}
+
+// BuildVarsFunc --------------------------------------------------------------
+
+// BuildVarsFunc is the function signature used by custom build variable
+// functions (which can modify route variables before a route's URL is built).
+type BuildVarsFunc func(map[string]string) map[string]string
+
+// BuildVarsFunc adds a custom function to be used to modify build variables
+// before a route's URL is built.
+func (r *Route) BuildVarsFunc(f BuildVarsFunc) *Route {
+	r.buildVarsFunc = f
+	return r
+}
+
+// Subrouter ------------------------------------------------------------------
+
+// Subrouter creates a subrouter for the route.
+//
+// It will test the inner routes only if the parent route matched. For example:
+//
+//     r := mux.NewRouter()
+//     s := r.Host("www.example.com").Subrouter()
+//     s.HandleFunc("/products/", ProductsHandler)
+//     s.HandleFunc("/products/{key}", ProductHandler)
+//     s.HandleFunc("/articles/{category}/{id:[0-9]+}"), ArticleHandler)
+//
+// Here, the routes registered in the subrouter won't be tested if the host
+// doesn't match.
+func (r *Route) Subrouter() *Router {
+	router := &Router{parent: r, strictSlash: r.strictSlash}
+	r.addMatcher(router)
+	return router
+}
+
+// ----------------------------------------------------------------------------
+// URL building
+// ----------------------------------------------------------------------------
+
+// URL builds a URL for the route.
+//
+// It accepts a sequence of key/value pairs for the route variables. For
+// example, given this route:
+//
+//     r := mux.NewRouter()
+//     r.HandleFunc("/articles/{category}/{id:[0-9]+}", ArticleHandler).
+//       Name("article")
+//
+// ...a URL for it can be built using:
+//
+//     url, err := r.Get("article").URL("category", "technology", "id", "42")
+//
+// ...which will return an url.URL with the following path:
+//
+//     "/articles/technology/42"
+//
+// This also works for host variables:
+//
+//     r := mux.NewRouter()
+//     r.Host("{subdomain}.domain.com").
+//       HandleFunc("/articles/{category}/{id:[0-9]+}", ArticleHandler).
+//       Name("article")
+//
+//     // url.String() will be "http://news.domain.com/articles/technology/42"
+//     url, err := r.Get("article").URL("subdomain", "news",
+//                                      "category", "technology",
+//                                      "id", "42")
+//
+// All variables defined in the route are required, and their values must
+// conform to the corresponding patterns.
+func (r *Route) URL(pairs ...string) (*url.URL, error) {
+	if r.err != nil {
+		return nil, r.err
+	}
+	if r.regexp == nil {
+		return nil, errors.New("mux: route doesn't have a host or path")
+	}
+	values, err := r.prepareVars(pairs...)
+	if err != nil {
+		return nil, err
+	}
+	var scheme, host, path string
+	if r.regexp.host != nil {
+		// Set a default scheme.
+		scheme = "http"
+		if host, err = r.regexp.host.url(values); err != nil {
+			return nil, err
+		}
+	}
+	if r.regexp.path != nil {
+		if path, err = r.regexp.path.url(values); err != nil {
+			return nil, err
+		}
+	}
+	return &url.URL{
+		Scheme: scheme,
+		Host:   host,
+		Path:   path,
+	}, nil
+}
+
+// URLHost builds the host part of the URL for a route. See Route.URL().
+//
+// The route must have a host defined.
+func (r *Route) URLHost(pairs ...string) (*url.URL, error) {
+	if r.err != nil {
+		return nil, r.err
+	}
+	if r.regexp == nil || r.regexp.host == nil {
+		return nil, errors.New("mux: route doesn't have a host")
+	}
+	values, err := r.prepareVars(pairs...)
+	if err != nil {
+		return nil, err
+	}
+	host, err := r.regexp.host.url(values)
+	if err != nil {
+		return nil, err
+	}
+	return &url.URL{
+		Scheme: "http",
+		Host:   host,
+	}, nil
+}
+
+// URLPath builds the path part of the URL for a route. See Route.URL().
+//
+// The route must have a path defined.
+func (r *Route) URLPath(pairs ...string) (*url.URL, error) {
+	if r.err != nil {
+		return nil, r.err
+	}
+	if r.regexp == nil || r.regexp.path == nil {
+		return nil, errors.New("mux: route doesn't have a path")
+	}
+	values, err := r.prepareVars(pairs...)
+	if err != nil {
+		return nil, err
+	}
+	path, err := r.regexp.path.url(values)
+	if err != nil {
+		return nil, err
+	}
+	return &url.URL{
+		Path: path,
+	}, nil
+}
+
+// GetPathTemplate returns the template used to build the
+// route match.
+// This is useful for building simple REST API documentation and for instrumentation
+// against third-party services.
+// An error will be returned if the route does not define a path.
+func (r *Route) GetPathTemplate() (string, error) {
+	if r.err != nil {
+		return "", r.err
+	}
+	if r.regexp == nil || r.regexp.path == nil {
+		return "", errors.New("mux: route doesn't have a path")
+	}
+	return r.regexp.path.template, nil
+}
+
+// GetHostTemplate returns the template used to build the
+// route match.
+// This is useful for building simple REST API documentation and for instrumentation
+// against third-party services.
+// An error will be returned if the route does not define a host.
+func (r *Route) GetHostTemplate() (string, error) {
+	if r.err != nil {
+		return "", r.err
+	}
+	if r.regexp == nil || r.regexp.host == nil {
+		return "", errors.New("mux: route doesn't have a host")
+	}
+	return r.regexp.host.template, nil
+}
+
+// prepareVars converts the route variable pairs into a map. If the route has a
+// BuildVarsFunc, it is invoked.
+func (r *Route) prepareVars(pairs ...string) (map[string]string, error) {
+	m, err := mapFromPairsToString(pairs...)
+	if err != nil {
+		return nil, err
+	}
+	return r.buildVars(m), nil
+}
+
+func (r *Route) buildVars(m map[string]string) map[string]string {
+	if r.parent != nil {
+		m = r.parent.buildVars(m)
+	}
+	if r.buildVarsFunc != nil {
+		m = r.buildVarsFunc(m)
+	}
+	return m
+}
+
+// ----------------------------------------------------------------------------
+// parentRoute
+// ----------------------------------------------------------------------------
+
+// parentRoute allows routes to know about parent host and path definitions.
+type parentRoute interface {
+	getNamedRoutes() map[string]*Route
+	getRegexpGroup() *routeRegexpGroup
+	buildVars(map[string]string) map[string]string
+}
+
+// getNamedRoutes returns the map where named routes are registered.
+func (r *Route) getNamedRoutes() map[string]*Route {
+	if r.parent == nil {
+		// During tests router is not always set.
+		r.parent = NewRouter()
+	}
+	return r.parent.getNamedRoutes()
+}
+
+// getRegexpGroup returns regexp definitions from this route.
+func (r *Route) getRegexpGroup() *routeRegexpGroup {
+	if r.regexp == nil {
+		if r.parent == nil {
+			// During tests router is not always set.
+			r.parent = NewRouter()
+		}
+		regexp := r.parent.getRegexpGroup()
+		if regexp == nil {
+			r.regexp = new(routeRegexpGroup)
+		} else {
+			// Copy.
+			r.regexp = &routeRegexpGroup{
+				host:    regexp.host,
+				path:    regexp.path,
+				queries: regexp.queries,
+			}
+		}
+	}
+	return r.regexp
+}

vendor/github.com/gorilla/websocket/.gitignore

@@ -0,0 +1,22 @@
+# Compiled Object files, Static and Dynamic libs (Shared Objects)
+*.o
+*.a
+*.so
+
+# Folders
+_obj
+_test
+
+# Architecture specific extensions/prefixes
+*.[568vq]
+[568vq].out
+
+*.cgo1.go
+*.cgo2.c
+_cgo_defun.c
+_cgo_gotypes.go
+_cgo_export.*
+
+_testmain.go
+
+*.exe

vendor/github.com/gorilla/websocket/.travis.yml

@@ -0,0 +1,17 @@
+language: go
+sudo: false
+
+matrix:
+  include:
+    - go: 1.4
+    - go: 1.5
+    - go: 1.6
+    - go: tip
+  allow_failures:
+    - go: tip
+
+script:
+  - go get -t -v ./...
+  - diff -u <(echo -n) <(gofmt -d .)
+  - go vet $(go list ./... | grep -v /vendor/)
+  - go test -v -race ./...

vendor/github.com/gorilla/websocket/AUTHORS

@@ -0,0 +1,8 @@
+# This is the official list of Gorilla WebSocket authors for copyright
+# purposes.
+#
+# Please keep the list sorted.
+
+Gary Burd <gary@beagledreams.com>
+Joachim Bauch <mail@joachim-bauch.de>
+

vendor/github.com/gorilla/websocket/LICENSE

@@ -0,0 +1,22 @@
+Copyright (c) 2013 The Gorilla WebSocket Authors. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+  Redistributions of source code must retain the above copyright notice, this
+  list of conditions and the following disclaimer.
+
+  Redistributions in binary form must reproduce the above copyright notice,
+  this list of conditions and the following disclaimer in the documentation
+  and/or other materials provided with the distribution.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

vendor/github.com/gorilla/websocket/README.md

@@ -0,0 +1,61 @@
+# Gorilla WebSocket
+
+Gorilla WebSocket is a [Go](http://golang.org/) implementation of the
+[WebSocket](http://www.rfc-editor.org/rfc/rfc6455.txt) protocol.
+
+### Documentation
+
+* [API Reference](http://godoc.org/github.com/gorilla/websocket)
+* [Chat example](https://github.com/gorilla/websocket/tree/master/examples/chat)
+* [Command example](https://github.com/gorilla/websocket/tree/master/examples/command)
+* [Client and server example](https://github.com/gorilla/websocket/tree/master/examples/echo)
+* [File watch example](https://github.com/gorilla/websocket/tree/master/examples/filewatch)
+
+### Status
+
+The Gorilla WebSocket package provides a complete and tested implementation of
+the [WebSocket](http://www.rfc-editor.org/rfc/rfc6455.txt) protocol. The
+package API is stable.
+
+### Installation
+
+    go get github.com/gorilla/websocket
+
+### Protocol Compliance
+
+The Gorilla WebSocket package passes the server tests in the [Autobahn Test
+Suite](http://autobahn.ws/testsuite) using the application in the [examples/autobahn
+subdirectory](https://github.com/gorilla/websocket/tree/master/examples/autobahn).
+
+### Gorilla WebSocket compared with other packages
+
+<table>
+<tr>
+<th></th>
+<th><a href="http://godoc.org/github.com/gorilla/websocket">github.com/gorilla</a></th>
+<th><a href="http://godoc.org/golang.org/x/net/websocket">golang.org/x/net</a></th>
+</tr>
+<tr>
+<tr><td colspan="3"><a href="http://tools.ietf.org/html/rfc6455">RFC 6455</a> Features</td></tr>
+<tr><td>Passes <a href="http://autobahn.ws/testsuite/">Autobahn Test Suite</a></td><td><a href="https://github.com/gorilla/websocket/tree/master/examples/autobahn">Yes</a></td><td>No</td></tr>
+<tr><td>Receive <a href="https://tools.ietf.org/html/rfc6455#section-5.4">fragmented</a> message<td>Yes</td><td><a href="https://code.google.com/p/go/issues/detail?id=7632">No</a>, see note 1</td></tr>
+<tr><td>Send <a href="https://tools.ietf.org/html/rfc6455#section-5.5.1">close</a> message</td><td><a href="http://godoc.org/github.com/gorilla/websocket#hdr-Control_Messages">Yes</a></td><td><a href="https://code.google.com/p/go/issues/detail?id=4588">No</a></td></tr>
+<tr><td>Send <a href="https://tools.ietf.org/html/rfc6455#section-5.5.2">pings</a> and receive <a href="https://tools.ietf.org/html/rfc6455#section-5.5.3">pongs</a></td><td><a href="http://godoc.org/github.com/gorilla/websocket#hdr-Control_Messages">Yes</a></td><td>No</td></tr>
+<tr><td>Get the <a href="https://tools.ietf.org/html/rfc6455#section-5.6">type</a> of a received data message</td><td>Yes</td><td>Yes, see note 2</td></tr>
+<tr><td colspan="3">Other Features</tr></td>
+<tr><td>Limit size of received message</td><td><a href="http://godoc.org/github.com/gorilla/websocket#Conn.SetReadLimit">Yes</a></td><td><a href="https://code.google.com/p/go/issues/detail?id=5082">No</a></td></tr>
+<tr><td>Read message using io.Reader</td><td><a href="http://godoc.org/github.com/gorilla/websocket#Conn.NextReader">Yes</a></td><td>No, see note 3</td></tr>
+<tr><td>Write message using io.WriteCloser</td><td><a href="http://godoc.org/github.com/gorilla/websocket#Conn.NextWriter">Yes</a></td><td>No, see note 3</td></tr>
+</table>
+
+Notes: 
+
+1. Large messages are fragmented in [Chrome's new WebSocket implementation](http://www.ietf.org/mail-archive/web/hybi/current/msg10503.html).
+2. The application can get the type of a received data message by implementing
+   a [Codec marshal](http://godoc.org/golang.org/x/net/websocket#Codec.Marshal)
+   function.
+3. The go.net io.Reader and io.Writer operate across WebSocket frame boundaries.
+  Read returns when the input buffer is full or a frame boundary is
+  encountered. Each call to Write sends a single frame message. The Gorilla
+  io.Reader and io.WriteCloser operate on a single WebSocket message.
+

vendor/github.com/gorilla/websocket/client.go

@@ -0,0 +1,375 @@
+// Copyright 2013 The Gorilla WebSocket Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package websocket
+
+import (
+	"bufio"
+	"bytes"
+	"crypto/tls"
+	"encoding/base64"
+	"errors"
+	"io"
+	"io/ioutil"
+	"net"
+	"net/http"
+	"net/url"
+	"strings"
+	"time"
+)
+
+// ErrBadHandshake is returned when the server response to opening handshake is
+// invalid.
+var ErrBadHandshake = errors.New("websocket: bad handshake")
+
+// NewClient creates a new client connection using the given net connection.
+// The URL u specifies the host and request URI. Use requestHeader to specify
+// the origin (Origin), subprotocols (Sec-WebSocket-Protocol) and cookies
+// (Cookie). Use the response.Header to get the selected subprotocol
+// (Sec-WebSocket-Protocol) and cookies (Set-Cookie).
+//
+// If the WebSocket handshake fails, ErrBadHandshake is returned along with a
+// non-nil *http.Response so that callers can handle redirects, authentication,
+// etc.
+//
+// Deprecated: Use Dialer instead.
+func NewClient(netConn net.Conn, u *url.URL, requestHeader http.Header, readBufSize, writeBufSize int) (c *Conn, response *http.Response, err error) {
+	d := Dialer{
+		ReadBufferSize:  readBufSize,
+		WriteBufferSize: writeBufSize,
+		NetDial: func(net, addr string) (net.Conn, error) {
+			return netConn, nil
+		},
+	}
+	return d.Dial(u.String(), requestHeader)
+}
+
+// A Dialer contains options for connecting to WebSocket server.
+type Dialer struct {
+	// NetDial specifies the dial function for creating TCP connections. If
+	// NetDial is nil, net.Dial is used.
+	NetDial func(network, addr string) (net.Conn, error)
+
+	// Proxy specifies a function to return a proxy for a given
+	// Request. If the function returns a non-nil error, the
+	// request is aborted with the provided error.
+	// If Proxy is nil or returns a nil *URL, no proxy is used.
+	Proxy func(*http.Request) (*url.URL, error)
+
+	// TLSClientConfig specifies the TLS configuration to use with tls.Client.
+	// If nil, the default configuration is used.
+	TLSClientConfig *tls.Config
+
+	// HandshakeTimeout specifies the duration for the handshake to complete.
+	HandshakeTimeout time.Duration
+
+	// Input and output buffer sizes. If the buffer size is zero, then a
+	// default value of 4096 is used.
+	ReadBufferSize, WriteBufferSize int
+
+	// Subprotocols specifies the client's requested subprotocols.
+	Subprotocols []string
+}
+
+var errMalformedURL = errors.New("malformed ws or wss URL")
+
+// parseURL parses the URL.
+//
+// This function is a replacement for the standard library url.Parse function.
+// In Go 1.4 and earlier, url.Parse loses information from the path.
+func parseURL(s string) (*url.URL, error) {
+	// From the RFC:
+	//
+	// ws-URI = "ws:" "//" host [ ":" port ] path [ "?" query ]
+	// wss-URI = "wss:" "//" host [ ":" port ] path [ "?" query ]
+
+	var u url.URL
+	switch {
+	case strings.HasPrefix(s, "ws://"):
+		u.Scheme = "ws"
+		s = s[len("ws://"):]
+	case strings.HasPrefix(s, "wss://"):
+		u.Scheme = "wss"
+		s = s[len("wss://"):]
+	default:
+		return nil, errMalformedURL
+	}
+
+	if i := strings.Index(s, "?"); i >= 0 {
+		u.RawQuery = s[i+1:]
+		s = s[:i]
+	}
+
+	if i := strings.Index(s, "/"); i >= 0 {
+		u.Opaque = s[i:]
+		s = s[:i]
+	} else {
+		u.Opaque = "/"
+	}
+
+	u.Host = s
+
+	if strings.Contains(u.Host, "@") {
+		// Don't bother parsing user information because user information is
+		// not allowed in websocket URIs.
+		return nil, errMalformedURL
+	}
+
+	return &u, nil
+}
+
+func hostPortNoPort(u *url.URL) (hostPort, hostNoPort string) {
+	hostPort = u.Host
+	hostNoPort = u.Host
+	if i := strings.LastIndex(u.Host, ":"); i > strings.LastIndex(u.Host, "]") {
+		hostNoPort = hostNoPort[:i]
+	} else {
+		switch u.Scheme {
+		case "wss":
+			hostPort += ":443"
+		case "https":
+			hostPort += ":443"
+		default:
+			hostPort += ":80"
+		}
+	}
+	return hostPort, hostNoPort
+}
+
+// DefaultDialer is a dialer with all fields set to the default zero values.
+var DefaultDialer = &Dialer{
+	Proxy: http.ProxyFromEnvironment,
+}
+
+// Dial creates a new client connection. Use requestHeader to specify the
+// origin (Origin), subprotocols (Sec-WebSocket-Protocol) and cookies (Cookie).
+// Use the response.Header to get the selected subprotocol
+// (Sec-WebSocket-Protocol) and cookies (Set-Cookie).
+//
+// If the WebSocket handshake fails, ErrBadHandshake is returned along with a
+// non-nil *http.Response so that callers can handle redirects, authentication,
+// etcetera. The response body may not contain the entire response and does not
+// need to be closed by the application.
+func (d *Dialer) Dial(urlStr string, requestHeader http.Header) (*Conn, *http.Response, error) {
+
+	if d == nil {
+		d = &Dialer{
+			Proxy: http.ProxyFromEnvironment,
+		}
+	}
+
+	challengeKey, err := generateChallengeKey()
+	if err != nil {
+		return nil, nil, err
+	}
+
+	u, err := parseURL(urlStr)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	switch u.Scheme {
+	case "ws":
+		u.Scheme = "http"
+	case "wss":
+		u.Scheme = "https"
+	default:
+		return nil, nil, errMalformedURL
+	}
+
+	if u.User != nil {
+		// User name and password are not allowed in websocket URIs.
+		return nil, nil, errMalformedURL
+	}
+
+	req := &http.Request{
+		Method:     "GET",
+		URL:        u,
+		Proto:      "HTTP/1.1",
+		ProtoMajor: 1,
+		ProtoMinor: 1,
+		Header:     make(http.Header),
+		Host:       u.Host,
+	}
+
+	// Set the request headers using the capitalization for names and values in
+	// RFC examples. Although the capitalization shouldn't matter, there are
+	// servers that depend on it. The Header.Set method is not used because the
+	// method canonicalizes the header names.
+	req.Header["Upgrade"] = []string{"websocket"}
+	req.Header["Connection"] = []string{"Upgrade"}
+	req.Header["Sec-WebSocket-Key"] = []string{challengeKey}
+	req.Header["Sec-WebSocket-Version"] = []string{"13"}
+	if len(d.Subprotocols) > 0 {
+		req.Header["Sec-WebSocket-Protocol"] = []string{strings.Join(d.Subprotocols, ", ")}
+	}
+	for k, vs := range requestHeader {
+		switch {
+		case k == "Host":
+			if len(vs) > 0 {
+				req.Host = vs[0]
+			}
+		case k == "Upgrade" ||
+			k == "Connection" ||
+			k == "Sec-Websocket-Key" ||
+			k == "Sec-Websocket-Version" ||
+			(k == "Sec-Websocket-Protocol" && len(d.Subprotocols) > 0):
+			return nil, nil, errors.New("websocket: duplicate header not allowed: " + k)
+		default:
+			req.Header[k] = vs
+		}
+	}
+
+	hostPort, hostNoPort := hostPortNoPort(u)
+
+	var proxyURL *url.URL
+	// Check wether the proxy method has been configured
+	if d.Proxy != nil {
+		proxyURL, err = d.Proxy(req)
+	}
+	if err != nil {
+		return nil, nil, err
+	}
+
+	var targetHostPort string
+	if proxyURL != nil {
+		targetHostPort, _ = hostPortNoPort(proxyURL)
+	} else {
+		targetHostPort = hostPort
+	}
+
+	var deadline time.Time
+	if d.HandshakeTimeout != 0 {
+		deadline = time.Now().Add(d.HandshakeTimeout)
+	}
+
+	netDial := d.NetDial
+	if netDial == nil {
+		netDialer := &net.Dialer{Deadline: deadline}
+		netDial = netDialer.Dial
+	}
+
+	netConn, err := netDial("tcp", targetHostPort)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	defer func() {
+		if netConn != nil {
+			netConn.Close()
+		}
+	}()
+
+	if err := netConn.SetDeadline(deadline); err != nil {
+		return nil, nil, err
+	}
+
+	if proxyURL != nil {
+		connectHeader := make(http.Header)
+		if user := proxyURL.User; user != nil {
+			proxyUser := user.Username()
+			if proxyPassword, passwordSet := user.Password(); passwordSet {
+				credential := base64.StdEncoding.EncodeToString([]byte(proxyUser + ":" + proxyPassword))
+				connectHeader.Set("Proxy-Authorization", "Basic "+credential)
+			}
+		}
+		connectReq := &http.Request{
+			Method: "CONNECT",
+			URL:    &url.URL{Opaque: hostPort},
+			Host:   hostPort,
+			Header: connectHeader,
+		}
+
+		connectReq.Write(netConn)
+
+		// Read response.
+		// Okay to use and discard buffered reader here, because
+		// TLS server will not speak until spoken to.
+		br := bufio.NewReader(netConn)
+		resp, err := http.ReadResponse(br, connectReq)
+		if err != nil {
+			return nil, nil, err
+		}
+		if resp.StatusCode != 200 {
+			f := strings.SplitN(resp.Status, " ", 2)
+			return nil, nil, errors.New(f[1])
+		}
+	}
+
+	if u.Scheme == "https" {
+		cfg := cloneTLSConfig(d.TLSClientConfig)
+		if cfg.ServerName == "" {
+			cfg.ServerName = hostNoPort
+		}
+		tlsConn := tls.Client(netConn, cfg)
+		netConn = tlsConn
+		if err := tlsConn.Handshake(); err != nil {
+			return nil, nil, err
+		}
+		if !cfg.InsecureSkipVerify {
+			if err := tlsConn.VerifyHostname(cfg.ServerName); err != nil {
+				return nil, nil, err
+			}
+		}
+	}
+
+	conn := newConn(netConn, false, d.ReadBufferSize, d.WriteBufferSize)
+
+	if err := req.Write(netConn); err != nil {
+		return nil, nil, err
+	}
+
+	resp, err := http.ReadResponse(conn.br, req)
+	if err != nil {
+		return nil, nil, err
+	}
+	if resp.StatusCode != 101 ||
+		!strings.EqualFold(resp.Header.Get("Upgrade"), "websocket") ||
+		!strings.EqualFold(resp.Header.Get("Connection"), "upgrade") ||
+		resp.Header.Get("Sec-Websocket-Accept") != computeAcceptKey(challengeKey) {
+		// Before closing the network connection on return from this
+		// function, slurp up some of the response to aid application
+		// debugging.
+		buf := make([]byte, 1024)
+		n, _ := io.ReadFull(resp.Body, buf)
+		resp.Body = ioutil.NopCloser(bytes.NewReader(buf[:n]))
+		return nil, resp, ErrBadHandshake
+	}
+
+	resp.Body = ioutil.NopCloser(bytes.NewReader([]byte{}))
+	conn.subprotocol = resp.Header.Get("Sec-Websocket-Protocol")
+
+	netConn.SetDeadline(time.Time{})
+	netConn = nil // to avoid close in defer.
+	return conn, resp, nil
+}
+
+// cloneTLSConfig clones all public fields except the fields
+// SessionTicketsDisabled and SessionTicketKey. This avoids copying the
+// sync.Mutex in the sync.Once and makes it safe to call cloneTLSConfig on a
+// config in active use.
+func cloneTLSConfig(cfg *tls.Config) *tls.Config {
+	if cfg == nil {
+		return &tls.Config{}
+	}
+	return &tls.Config{
+		Rand:                     cfg.Rand,
+		Time:                     cfg.Time,
+		Certificates:             cfg.Certificates,
+		NameToCertificate:        cfg.NameToCertificate,
+		GetCertificate:           cfg.GetCertificate,
+		RootCAs:                  cfg.RootCAs,
+		NextProtos:               cfg.NextProtos,
+		ServerName:               cfg.ServerName,
+		ClientAuth:               cfg.ClientAuth,
+		ClientCAs:                cfg.ClientCAs,
+		InsecureSkipVerify:       cfg.InsecureSkipVerify,
+		CipherSuites:             cfg.CipherSuites,
+		PreferServerCipherSuites: cfg.PreferServerCipherSuites,
+		ClientSessionCache:       cfg.ClientSessionCache,
+		MinVersion:               cfg.MinVersion,
+		MaxVersion:               cfg.MaxVersion,
+		CurvePreferences:         cfg.CurvePreferences,
+	}
+}

vendor/github.com/gorilla/websocket/conn.go

@@ -0,0 +1,950 @@
+// Copyright 2013 The Gorilla WebSocket Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package websocket
+
+import (
+	"bufio"
+	"encoding/binary"
+	"errors"
+	"io"
+	"io/ioutil"
+	"math/rand"
+	"net"
+	"strconv"
+	"time"
+	"unicode/utf8"
+)
+
+const (
+	maxFrameHeaderSize         = 2 + 8 + 4 // Fixed header + length + mask
+	maxControlFramePayloadSize = 125
+	finalBit                   = 1 << 7
+	maskBit                    = 1 << 7
+	writeWait                  = time.Second
+
+	defaultReadBufferSize  = 4096
+	defaultWriteBufferSize = 4096
+
+	continuationFrame = 0
+	noFrame           = -1
+)
+
+// Close codes defined in RFC 6455, section 11.7.
+const (
+	CloseNormalClosure           = 1000
+	CloseGoingAway               = 1001
+	CloseProtocolError           = 1002
+	CloseUnsupportedData         = 1003
+	CloseNoStatusReceived        = 1005
+	CloseAbnormalClosure         = 1006
+	CloseInvalidFramePayloadData = 1007
+	ClosePolicyViolation         = 1008
+	CloseMessageTooBig           = 1009
+	CloseMandatoryExtension      = 1010
+	CloseInternalServerErr       = 1011
+	CloseServiceRestart          = 1012
+	CloseTryAgainLater           = 1013
+	CloseTLSHandshake            = 1015
+)
+
+// The message types are defined in RFC 6455, section 11.8.
+const (
+	// TextMessage denotes a text data message. The text message payload is
+	// interpreted as UTF-8 encoded text data.
+	TextMessage = 1
+
+	// BinaryMessage denotes a binary data message.
+	BinaryMessage = 2
+
+	// CloseMessage denotes a close control message. The optional message
+	// payload contains a numeric code and text. Use the FormatCloseMessage
+	// function to format a close message payload.
+	CloseMessage = 8
+
+	// PingMessage denotes a ping control message. The optional message payload
+	// is UTF-8 encoded text.
+	PingMessage = 9
+
+	// PongMessage denotes a ping control message. The optional message payload
+	// is UTF-8 encoded text.
+	PongMessage = 10
+)
+
+// ErrCloseSent is returned when the application writes a message to the
+// connection after sending a close message.
+var ErrCloseSent = errors.New("websocket: close sent")
+
+// ErrReadLimit is returned when reading a message that is larger than the
+// read limit set for the connection.
+var ErrReadLimit = errors.New("websocket: read limit exceeded")
+
+// netError satisfies the net Error interface.
+type netError struct {
+	msg       string
+	temporary bool
+	timeout   bool
+}
+
+func (e *netError) Error() string   { return e.msg }
+func (e *netError) Temporary() bool { return e.temporary }
+func (e *netError) Timeout() bool   { return e.timeout }
+
+// CloseError represents close frame.
+type CloseError struct {
+
+	// Code is defined in RFC 6455, section 11.7.
+	Code int
+
+	// Text is the optional text payload.
+	Text string
+}
+
+func (e *CloseError) Error() string {
+	s := []byte("websocket: close ")
+	s = strconv.AppendInt(s, int64(e.Code), 10)
+	switch e.Code {
+	case CloseNormalClosure:
+		s = append(s, " (normal)"...)
+	case CloseGoingAway:
+		s = append(s, " (going away)"...)
+	case CloseProtocolError:
+		s = append(s, " (protocol error)"...)
+	case CloseUnsupportedData:
+		s = append(s, " (unsupported data)"...)
+	case CloseNoStatusReceived:
+		s = append(s, " (no status)"...)
+	case CloseAbnormalClosure:
+		s = append(s, " (abnormal closure)"...)
+	case CloseInvalidFramePayloadData:
+		s = append(s, " (invalid payload data)"...)
+	case ClosePolicyViolation:
+		s = append(s, " (policy violation)"...)
+	case CloseMessageTooBig:
+		s = append(s, " (message too big)"...)
+	case CloseMandatoryExtension:
+		s = append(s, " (mandatory extension missing)"...)
+	case CloseInternalServerErr:
+		s = append(s, " (internal server error)"...)
+	case CloseTLSHandshake:
+		s = append(s, " (TLS handshake error)"...)
+	}
+	if e.Text != "" {
+		s = append(s, ": "...)
+		s = append(s, e.Text...)
+	}
+	return string(s)
+}
+
+// IsCloseError returns boolean indicating whether the error is a *CloseError
+// with one of the specified codes.
+func IsCloseError(err error, codes ...int) bool {
+	if e, ok := err.(*CloseError); ok {
+		for _, code := range codes {
+			if e.Code == code {
+				return true
+			}
+		}
+	}
+	return false
+}
+
+// IsUnexpectedCloseError returns boolean indicating whether the error is a
+// *CloseError with a code not in the list of expected codes.
+func IsUnexpectedCloseError(err error, expectedCodes ...int) bool {
+	if e, ok := err.(*CloseError); ok {
+		for _, code := range expectedCodes {
+			if e.Code == code {
+				return false
+			}
+		}
+		return true
+	}
+	return false
+}
+
+var (
+	errWriteTimeout        = &netError{msg: "websocket: write timeout", timeout: true, temporary: true}
+	errUnexpectedEOF       = &CloseError{Code: CloseAbnormalClosure, Text: io.ErrUnexpectedEOF.Error()}
+	errBadWriteOpCode      = errors.New("websocket: bad write message type")
+	errWriteClosed         = errors.New("websocket: write closed")
+	errInvalidControlFrame = errors.New("websocket: invalid control frame")
+)
+
+func hideTempErr(err error) error {
+	if e, ok := err.(net.Error); ok && e.Temporary() {
+		err = &netError{msg: e.Error(), timeout: e.Timeout()}
+	}
+	return err
+}
+
+func isControl(frameType int) bool {
+	return frameType == CloseMessage || frameType == PingMessage || frameType == PongMessage
+}
+
+func isData(frameType int) bool {
+	return frameType == TextMessage || frameType == BinaryMessage
+}
+
+var validReceivedCloseCodes = map[int]bool{
+	// see http://www.iana.org/assignments/websocket/websocket.xhtml#close-code-number
+
+	CloseNormalClosure:           true,
+	CloseGoingAway:               true,
+	CloseProtocolError:           true,
+	CloseUnsupportedData:         true,
+	CloseNoStatusReceived:        false,
+	CloseAbnormalClosure:         false,
+	CloseInvalidFramePayloadData: true,
+	ClosePolicyViolation:         true,
+	CloseMessageTooBig:           true,
+	CloseMandatoryExtension:      true,
+	CloseInternalServerErr:       true,
+	CloseServiceRestart:          true,
+	CloseTryAgainLater:           true,
+	CloseTLSHandshake:            false,
+}
+
+func isValidReceivedCloseCode(code int) bool {
+	return validReceivedCloseCodes[code] || (code >= 3000 && code <= 4999)
+}
+
+func maskBytes(key [4]byte, pos int, b []byte) int {
+	for i := range b {
+		b[i] ^= key[pos&3]
+		pos++
+	}
+	return pos & 3
+}
+
+func newMaskKey() [4]byte {
+	n := rand.Uint32()
+	return [4]byte{byte(n), byte(n >> 8), byte(n >> 16), byte(n >> 24)}
+}
+
+// Conn represents a WebSocket connection.
+type Conn struct {
+	conn        net.Conn
+	isServer    bool
+	subprotocol string
+
+	// Write fields
+	mu        chan bool // used as mutex to protect write to conn and closeSent
+	closeSent bool      // true if close message was sent
+
+	// Message writer fields.
+	writeErr       error
+	writeBuf       []byte // frame is constructed in this buffer.
+	writePos       int    // end of data in writeBuf.
+	writeFrameType int    // type of the current frame.
+	writeSeq       int    // incremented to invalidate message writers.
+	writeDeadline  time.Time
+	isWriting      bool // for best-effort concurrent write detection
+
+	// Read fields
+	readErr       error
+	br            *bufio.Reader
+	readRemaining int64 // bytes remaining in current frame.
+	readFinal     bool  // true the current message has more frames.
+	readSeq       int   // incremented to invalidate message readers.
+	readLength    int64 // Message size.
+	readLimit     int64 // Maximum message size.
+	readMaskPos   int
+	readMaskKey   [4]byte
+	handlePong    func(string) error
+	handlePing    func(string) error
+	readErrCount  int
+}
+
+func newConn(conn net.Conn, isServer bool, readBufferSize, writeBufferSize int) *Conn {
+	mu := make(chan bool, 1)
+	mu <- true
+
+	if readBufferSize == 0 {
+		readBufferSize = defaultReadBufferSize
+	}
+	if writeBufferSize == 0 {
+		writeBufferSize = defaultWriteBufferSize
+	}
+
+	c := &Conn{
+		isServer:       isServer,
+		br:             bufio.NewReaderSize(conn, readBufferSize),
+		conn:           conn,
+		mu:             mu,
+		readFinal:      true,
+		writeBuf:       make([]byte, writeBufferSize+maxFrameHeaderSize),
+		writeFrameType: noFrame,
+		writePos:       maxFrameHeaderSize,
+	}
+	c.SetPingHandler(nil)
+	c.SetPongHandler(nil)
+	return c
+}
+
+// Subprotocol returns the negotiated protocol for the connection.
+func (c *Conn) Subprotocol() string {
+	return c.subprotocol
+}
+
+// Close closes the underlying network connection without sending or waiting for a close frame.
+func (c *Conn) Close() error {
+	return c.conn.Close()
+}
+
+// LocalAddr returns the local network address.
+func (c *Conn) LocalAddr() net.Addr {
+	return c.conn.LocalAddr()
+}
+
+// RemoteAddr returns the remote network address.
+func (c *Conn) RemoteAddr() net.Addr {
+	return c.conn.RemoteAddr()
+}
+
+// Write methods
+
+func (c *Conn) write(frameType int, deadline time.Time, bufs ...[]byte) error {
+	<-c.mu
+	defer func() { c.mu <- true }()
+
+	if c.closeSent {
+		return ErrCloseSent
+	} else if frameType == CloseMessage {
+		c.closeSent = true
+	}
+
+	c.conn.SetWriteDeadline(deadline)
+	for _, buf := range bufs {
+		if len(buf) > 0 {
+			n, err := c.conn.Write(buf)
+			if n != len(buf) {
+				// Close on partial write.
+				c.conn.Close()
+			}
+			if err != nil {
+				return err
+			}
+		}
+	}
+	return nil
+}
+
+// WriteControl writes a control message with the given deadline. The allowed
+// message types are CloseMessage, PingMessage and PongMessage.
+func (c *Conn) WriteControl(messageType int, data []byte, deadline time.Time) error {
+	if !isControl(messageType) {
+		return errBadWriteOpCode
+	}
+	if len(data) > maxControlFramePayloadSize {
+		return errInvalidControlFrame
+	}
+
+	b0 := byte(messageType) | finalBit
+	b1 := byte(len(data))
+	if !c.isServer {
+		b1 |= maskBit
+	}
+
+	buf := make([]byte, 0, maxFrameHeaderSize+maxControlFramePayloadSize)
+	buf = append(buf, b0, b1)
+
+	if c.isServer {
+		buf = append(buf, data...)
+	} else {
+		key := newMaskKey()
+		buf = append(buf, key[:]...)
+		buf = append(buf, data...)
+		maskBytes(key, 0, buf[6:])
+	}
+
+	d := time.Hour * 1000
+	if !deadline.IsZero() {
+		d = deadline.Sub(time.Now())
+		if d < 0 {
+			return errWriteTimeout
+		}
+	}
+
+	timer := time.NewTimer(d)
+	select {
+	case <-c.mu:
+		timer.Stop()
+	case <-timer.C:
+		return errWriteTimeout
+	}
+	defer func() { c.mu <- true }()
+
+	if c.closeSent {
+		return ErrCloseSent
+	} else if messageType == CloseMessage {
+		c.closeSent = true
+	}
+
+	c.conn.SetWriteDeadline(deadline)
+	n, err := c.conn.Write(buf)
+	if n != 0 && n != len(buf) {
+		c.conn.Close()
+	}
+	return hideTempErr(err)
+}
+
+// NextWriter returns a writer for the next message to send.  The writer's
+// Close method flushes the complete message to the network.
+//
+// There can be at most one open writer on a connection. NextWriter closes the
+// previous writer if the application has not already done so.
+func (c *Conn) NextWriter(messageType int) (io.WriteCloser, error) {
+	if c.writeErr != nil {
+		return nil, c.writeErr
+	}
+
+	if c.writeFrameType != noFrame {
+		if err := c.flushFrame(true, nil); err != nil {
+			return nil, err
+		}
+	}
+
+	if !isControl(messageType) && !isData(messageType) {
+		return nil, errBadWriteOpCode
+	}
+
+	c.writeFrameType = messageType
+	return messageWriter{c, c.writeSeq}, nil
+}
+
+func (c *Conn) flushFrame(final bool, extra []byte) error {
+	length := c.writePos - maxFrameHeaderSize + len(extra)
+
+	// Check for invalid control frames.
+	if isControl(c.writeFrameType) &&
+		(!final || length > maxControlFramePayloadSize) {
+		c.writeSeq++
+		c.writeFrameType = noFrame
+		c.writePos = maxFrameHeaderSize
+		return errInvalidControlFrame
+	}
+
+	b0 := byte(c.writeFrameType)
+	if final {
+		b0 |= finalBit
+	}
+	b1 := byte(0)
+	if !c.isServer {
+		b1 |= maskBit
+	}
+
+	// Assume that the frame starts at beginning of c.writeBuf.
+	framePos := 0
+	if c.isServer {
+		// Adjust up if mask not included in the header.
+		framePos = 4
+	}
+
+	switch {
+	case length >= 65536:
+		c.writeBuf[framePos] = b0
+		c.writeBuf[framePos+1] = b1 | 127
+		binary.BigEndian.PutUint64(c.writeBuf[framePos+2:], uint64(length))
+	case length > 125:
+		framePos += 6
+		c.writeBuf[framePos] = b0
+		c.writeBuf[framePos+1] = b1 | 126
+		binary.BigEndian.PutUint16(c.writeBuf[framePos+2:], uint16(length))
+	default:
+		framePos += 8
+		c.writeBuf[framePos] = b0
+		c.writeBuf[framePos+1] = b1 | byte(length)
+	}
+
+	if !c.isServer {
+		key := newMaskKey()
+		copy(c.writeBuf[maxFrameHeaderSize-4:], key[:])
+		maskBytes(key, 0, c.writeBuf[maxFrameHeaderSize:c.writePos])
+		if len(extra) > 0 {
+			c.writeErr = errors.New("websocket: internal error, extra used in client mode")
+			return c.writeErr
+		}
+	}
+
+	// Write the buffers to the connection with best-effort detection of
+	// concurrent writes. See the concurrency section in the package
+	// documentation for more info.
+
+	if c.isWriting {
+		panic("concurrent write to websocket connection")
+	}
+	c.isWriting = true
+
+	c.writeErr = c.write(c.writeFrameType, c.writeDeadline, c.writeBuf[framePos:c.writePos], extra)
+
+	if !c.isWriting {
+		panic("concurrent write to websocket connection")
+	}
+	c.isWriting = false
+
+	// Setup for next frame.
+	c.writePos = maxFrameHeaderSize
+	c.writeFrameType = continuationFrame
+	if final {
+		c.writeSeq++
+		c.writeFrameType = noFrame
+	}
+	return c.writeErr
+}
+
+type messageWriter struct {
+	c   *Conn
+	seq int
+}
+
+func (w messageWriter) err() error {
+	c := w.c
+	if c.writeSeq != w.seq {
+		return errWriteClosed
+	}
+	if c.writeErr != nil {
+		return c.writeErr
+	}
+	return nil
+}
+
+func (w messageWriter) ncopy(max int) (int, error) {
+	n := len(w.c.writeBuf) - w.c.writePos
+	if n <= 0 {
+		if err := w.c.flushFrame(false, nil); err != nil {
+			return 0, err
+		}
+		n = len(w.c.writeBuf) - w.c.writePos
+	}
+	if n > max {
+		n = max
+	}
+	return n, nil
+}
+
+func (w messageWriter) write(final bool, p []byte) (int, error) {
+	if err := w.err(); err != nil {
+		return 0, err
+	}
+
+	if len(p) > 2*len(w.c.writeBuf) && w.c.isServer {
+		// Don't buffer large messages.
+		err := w.c.flushFrame(final, p)
+		if err != nil {
+			return 0, err
+		}
+		return len(p), nil
+	}
+
+	nn := len(p)
+	for len(p) > 0 {
+		n, err := w.ncopy(len(p))
+		if err != nil {
+			return 0, err
+		}
+		copy(w.c.writeBuf[w.c.writePos:], p[:n])
+		w.c.writePos += n
+		p = p[n:]
+	}
+	return nn, nil
+}
+
+func (w messageWriter) Write(p []byte) (int, error) {
+	return w.write(false, p)
+}
+
+func (w messageWriter) WriteString(p string) (int, error) {
+	if err := w.err(); err != nil {
+		return 0, err
+	}
+
+	nn := len(p)
+	for len(p) > 0 {
+		n, err := w.ncopy(len(p))
+		if err != nil {
+			return 0, err
+		}
+		copy(w.c.writeBuf[w.c.writePos:], p[:n])
+		w.c.writePos += n
+		p = p[n:]
+	}
+	return nn, nil
+}
+
+func (w messageWriter) ReadFrom(r io.Reader) (nn int64, err error) {
+	if err := w.err(); err != nil {
+		return 0, err
+	}
+	for {
+		if w.c.writePos == len(w.c.writeBuf) {
+			err = w.c.flushFrame(false, nil)
+			if err != nil {
+				break
+			}
+		}
+		var n int
+		n, err = r.Read(w.c.writeBuf[w.c.writePos:])
+		w.c.writePos += n
+		nn += int64(n)
+		if err != nil {
+			if err == io.EOF {
+				err = nil
+			}
+			break
+		}
+	}
+	return nn, err
+}
+
+func (w messageWriter) Close() error {
+	if err := w.err(); err != nil {
+		return err
+	}
+	return w.c.flushFrame(true, nil)
+}
+
+// WriteMessage is a helper method for getting a writer using NextWriter,
+// writing the message and closing the writer.
+func (c *Conn) WriteMessage(messageType int, data []byte) error {
+	wr, err := c.NextWriter(messageType)
+	if err != nil {
+		return err
+	}
+	w := wr.(messageWriter)
+	if _, err := w.write(true, data); err != nil {
+		return err
+	}
+	if c.writeSeq == w.seq {
+		if err := c.flushFrame(true, nil); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// SetWriteDeadline sets the write deadline on the underlying network
+// connection. After a write has timed out, the websocket state is corrupt and
+// all future writes will return an error. A zero value for t means writes will
+// not time out.
+func (c *Conn) SetWriteDeadline(t time.Time) error {
+	c.writeDeadline = t
+	return nil
+}
+
+// Read methods
+
+// readFull is like io.ReadFull except that io.EOF is never returned.
+func (c *Conn) readFull(p []byte) (err error) {
+	var n int
+	for n < len(p) && err == nil {
+		var nn int
+		nn, err = c.br.Read(p[n:])
+		n += nn
+	}
+	if n == len(p) {
+		err = nil
+	} else if err == io.EOF {
+		err = errUnexpectedEOF
+	}
+	return
+}
+
+func (c *Conn) advanceFrame() (int, error) {
+
+	// 1. Skip remainder of previous frame.
+
+	if c.readRemaining > 0 {
+		if _, err := io.CopyN(ioutil.Discard, c.br, c.readRemaining); err != nil {
+			return noFrame, err
+		}
+	}
+
+	// 2. Read and parse first two bytes of frame header.
+
+	var b [8]byte
+	if err := c.readFull(b[:2]); err != nil {
+		return noFrame, err
+	}
+
+	final := b[0]&finalBit != 0
+	frameType := int(b[0] & 0xf)
+	reserved := int((b[0] >> 4) & 0x7)
+	mask := b[1]&maskBit != 0
+	c.readRemaining = int64(b[1] & 0x7f)
+
+	if reserved != 0 {
+		return noFrame, c.handleProtocolError("unexpected reserved bits " + strconv.Itoa(reserved))
+	}
+
+	switch frameType {
+	case CloseMessage, PingMessage, PongMessage:
+		if c.readRemaining > maxControlFramePayloadSize {
+			return noFrame, c.handleProtocolError("control frame length > 125")
+		}
+		if !final {
+			return noFrame, c.handleProtocolError("control frame not final")
+		}
+	case TextMessage, BinaryMessage:
+		if !c.readFinal {
+			return noFrame, c.handleProtocolError("message start before final message frame")
+		}
+		c.readFinal = final
+	case continuationFrame:
+		if c.readFinal {
+			return noFrame, c.handleProtocolError("continuation after final message frame")
+		}
+		c.readFinal = final
+	default:
+		return noFrame, c.handleProtocolError("unknown opcode " + strconv.Itoa(frameType))
+	}
+
+	// 3. Read and parse frame length.
+
+	switch c.readRemaining {
+	case 126:
+		if err := c.readFull(b[:2]); err != nil {
+			return noFrame, err
+		}
+		c.readRemaining = int64(binary.BigEndian.Uint16(b[:2]))
+	case 127:
+		if err := c.readFull(b[:8]); err != nil {
+			return noFrame, err
+		}
+		c.readRemaining = int64(binary.BigEndian.Uint64(b[:8]))
+	}
+
+	// 4. Handle frame masking.
+
+	if mask != c.isServer {
+		return noFrame, c.handleProtocolError("incorrect mask flag")
+	}
+
+	if mask {
+		c.readMaskPos = 0
+		if err := c.readFull(c.readMaskKey[:]); err != nil {
+			return noFrame, err
+		}
+	}
+
+	// 5. For text and binary messages, enforce read limit and return.
+
+	if frameType == continuationFrame || frameType == TextMessage || frameType == BinaryMessage {
+
+		c.readLength += c.readRemaining
+		if c.readLimit > 0 && c.readLength > c.readLimit {
+			c.WriteControl(CloseMessage, FormatCloseMessage(CloseMessageTooBig, ""), time.Now().Add(writeWait))
+			return noFrame, ErrReadLimit
+		}
+
+		return frameType, nil
+	}
+
+	// 6. Read control frame payload.
+
+	var payload []byte
+	if c.readRemaining > 0 {
+		payload = make([]byte, c.readRemaining)
+		c.readRemaining = 0
+		if err := c.readFull(payload); err != nil {
+			return noFrame, err
+		}
+		if c.isServer {
+			maskBytes(c.readMaskKey, 0, payload)
+		}
+	}
+
+	// 7. Process control frame payload.
+
+	switch frameType {
+	case PongMessage:
+		if err := c.handlePong(string(payload)); err != nil {
+			return noFrame, err
+		}
+	case PingMessage:
+		if err := c.handlePing(string(payload)); err != nil {
+			return noFrame, err
+		}
+	case CloseMessage:
+		echoMessage := []byte{}
+		closeCode := CloseNoStatusReceived
+		closeText := ""
+		if len(payload) >= 2 {
+			echoMessage = payload[:2]
+			closeCode = int(binary.BigEndian.Uint16(payload))
+			if !isValidReceivedCloseCode(closeCode) {
+				return noFrame, c.handleProtocolError("invalid close code")
+			}
+			closeText = string(payload[2:])
+			if !utf8.ValidString(closeText) {
+				return noFrame, c.handleProtocolError("invalid utf8 payload in close frame")
+			}
+		}
+		c.WriteControl(CloseMessage, echoMessage, time.Now().Add(writeWait))
+		return noFrame, &CloseError{Code: closeCode, Text: closeText}
+	}
+
+	return frameType, nil
+}
+
+func (c *Conn) handleProtocolError(message string) error {
+	c.WriteControl(CloseMessage, FormatCloseMessage(CloseProtocolError, message), time.Now().Add(writeWait))
+	return errors.New("websocket: " + message)
+}
+
+// NextReader returns the next data message received from the peer. The
+// returned messageType is either TextMessage or BinaryMessage.
+//
+// There can be at most one open reader on a connection. NextReader discards
+// the previous message if the application has not already consumed it.
+//
+// Applications must break out of the application's read loop when this method
+// returns a non-nil error value. Errors returned from this method are
+// permanent. Once this method returns a non-nil error, all subsequent calls to
+// this method return the same error.
+func (c *Conn) NextReader() (messageType int, r io.Reader, err error) {
+
+	c.readSeq++
+	c.readLength = 0
+
+	for c.readErr == nil {
+		frameType, err := c.advanceFrame()
+		if err != nil {
+			c.readErr = hideTempErr(err)
+			break
+		}
+		if frameType == TextMessage || frameType == BinaryMessage {
+			return frameType, messageReader{c, c.readSeq}, nil
+		}
+	}
+
+	// Applications that do handle the error returned from this method spin in
+	// tight loop on connection failure. To help application developers detect
+	// this error, panic on repeated reads to the failed connection.
+	c.readErrCount++
+	if c.readErrCount >= 1000 {
+		panic("repeated read on failed websocket connection")
+	}
+
+	return noFrame, nil, c.readErr
+}
+
+type messageReader struct {
+	c   *Conn
+	seq int
+}
+
+func (r messageReader) Read(b []byte) (int, error) {
+
+	if r.seq != r.c.readSeq {
+		return 0, io.EOF
+	}
+
+	for r.c.readErr == nil {
+
+		if r.c.readRemaining > 0 {
+			if int64(len(b)) > r.c.readRemaining {
+				b = b[:r.c.readRemaining]
+			}
+			n, err := r.c.br.Read(b)
+			r.c.readErr = hideTempErr(err)
+			if r.c.isServer {
+				r.c.readMaskPos = maskBytes(r.c.readMaskKey, r.c.readMaskPos, b[:n])
+			}
+			r.c.readRemaining -= int64(n)
+			if r.c.readRemaining > 0 && r.c.readErr == io.EOF {
+				r.c.readErr = errUnexpectedEOF
+			}
+			return n, r.c.readErr
+		}
+
+		if r.c.readFinal {
+			r.c.readSeq++
+			return 0, io.EOF
+		}
+
+		frameType, err := r.c.advanceFrame()
+		switch {
+		case err != nil:
+			r.c.readErr = hideTempErr(err)
+		case frameType == TextMessage || frameType == BinaryMessage:
+			r.c.readErr = errors.New("websocket: internal error, unexpected text or binary in Reader")
+		}
+	}
+
+	err := r.c.readErr
+	if err == io.EOF && r.seq == r.c.readSeq {
+		err = errUnexpectedEOF
+	}
+	return 0, err
+}
+
+// ReadMessage is a helper method for getting a reader using NextReader and
+// reading from that reader to a buffer.
+func (c *Conn) ReadMessage() (messageType int, p []byte, err error) {
+	var r io.Reader
+	messageType, r, err = c.NextReader()
+	if err != nil {
+		return messageType, nil, err
+	}
+	p, err = ioutil.ReadAll(r)
+	return messageType, p, err
+}
+
+// SetReadDeadline sets the read deadline on the underlying network connection.
+// After a read has timed out, the websocket connection state is corrupt and
+// all future reads will return an error. A zero value for t means reads will
+// not time out.
+func (c *Conn) SetReadDeadline(t time.Time) error {
+	return c.conn.SetReadDeadline(t)
+}
+
+// SetReadLimit sets the maximum size for a message read from the peer. If a
+// message exceeds the limit, the connection sends a close frame to the peer
+// and returns ErrReadLimit to the application.
+func (c *Conn) SetReadLimit(limit int64) {
+	c.readLimit = limit
+}
+
+// SetPingHandler sets the handler for ping messages received from the peer.
+// The appData argument to h is the PING frame application data. The default
+// ping handler sends a pong to the peer.
+func (c *Conn) SetPingHandler(h func(appData string) error) {
+	if h == nil {
+		h = func(message string) error {
+			err := c.WriteControl(PongMessage, []byte(message), time.Now().Add(writeWait))
+			if err == ErrCloseSent {
+				return nil
+			} else if e, ok := err.(net.Error); ok && e.Temporary() {
+				return nil
+			}
+			return err
+		}
+	}
+	c.handlePing = h
+}
+
+// SetPongHandler sets the handler for pong messages received from the peer.
+// The appData argument to h is the PONG frame application data. The default
+// pong handler does nothing.
+func (c *Conn) SetPongHandler(h func(appData string) error) {
+	if h == nil {
+		h = func(string) error { return nil }
+	}
+	c.handlePong = h
+}
+
+// UnderlyingConn returns the internal net.Conn. This can be used to further
+// modifications to connection specific flags.
+func (c *Conn) UnderlyingConn() net.Conn {
+	return c.conn
+}
+
+// FormatCloseMessage formats closeCode and text as a WebSocket close message.
+func FormatCloseMessage(closeCode int, text string) []byte {
+	buf := make([]byte, 2+len(text))
+	binary.BigEndian.PutUint16(buf, uint16(closeCode))
+	copy(buf[2:], text)
+	return buf
+}

vendor/github.com/gorilla/websocket/doc.go

@@ -0,0 +1,152 @@
+// Copyright 2013 The Gorilla WebSocket Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package websocket implements the WebSocket protocol defined in RFC 6455.
+//
+// Overview
+//
+// The Conn type represents a WebSocket connection. A server application uses
+// the Upgrade function from an Upgrader object with a HTTP request handler
+// to get a pointer to a Conn:
+//
+//  var upgrader = websocket.Upgrader{
+//      ReadBufferSize:  1024,
+//      WriteBufferSize: 1024,
+//  }
+//
+//  func handler(w http.ResponseWriter, r *http.Request) {
+//      conn, err := upgrader.Upgrade(w, r, nil)
+//      if err != nil {
+//          log.Println(err)
+//          return
+//      }
+//      ... Use conn to send and receive messages.
+//  }
+//
+// Call the connection's WriteMessage and ReadMessage methods to send and
+// receive messages as a slice of bytes. This snippet of code shows how to echo
+// messages using these methods:
+//
+//  for {
+//      messageType, p, err := conn.ReadMessage()
+//      if err != nil {
+//          return
+//      }
+//      if err = conn.WriteMessage(messageType, p); err != nil {
+//          return err
+//      }
+//  }
+//
+// In above snippet of code, p is a []byte and messageType is an int with value
+// websocket.BinaryMessage or websocket.TextMessage.
+//
+// An application can also send and receive messages using the io.WriteCloser
+// and io.Reader interfaces. To send a message, call the connection NextWriter
+// method to get an io.WriteCloser, write the message to the writer and close
+// the writer when done. To receive a message, call the connection NextReader
+// method to get an io.Reader and read until io.EOF is returned. This snippet
+// shows how to echo messages using the NextWriter and NextReader methods:
+//
+//  for {
+//      messageType, r, err := conn.NextReader()
+//      if err != nil {
+//          return
+//      }
+//      w, err := conn.NextWriter(messageType)
+//      if err != nil {
+//          return err
+//      }
+//      if _, err := io.Copy(w, r); err != nil {
+//          return err
+//      }
+//      if err := w.Close(); err != nil {
+//          return err
+//      }
+//  }
+//
+// Data Messages
+//
+// The WebSocket protocol distinguishes between text and binary data messages.
+// Text messages are interpreted as UTF-8 encoded text. The interpretation of
+// binary messages is left to the application.
+//
+// This package uses the TextMessage and BinaryMessage integer constants to
+// identify the two data message types. The ReadMessage and NextReader methods
+// return the type of the received message. The messageType argument to the
+// WriteMessage and NextWriter methods specifies the type of a sent message.
+//
+// It is the application's responsibility to ensure that text messages are
+// valid UTF-8 encoded text.
+//
+// Control Messages
+//
+// The WebSocket protocol defines three types of control messages: close, ping
+// and pong. Call the connection WriteControl, WriteMessage or NextWriter
+// methods to send a control message to the peer.
+//
+// Connections handle received close messages by sending a close message to the
+// peer and returning a *CloseError from the the NextReader, ReadMessage or the
+// message Read method.
+//
+// Connections handle received ping and pong messages by invoking callback
+// functions set with SetPingHandler and SetPongHandler methods. The callback
+// functions are called from the NextReader, ReadMessage and the message Read
+// methods.
+//
+// The default ping handler sends a pong to the peer. The application's reading
+// goroutine can block for a short time while the handler writes the pong data
+// to the connection.
+//
+// The application must read the connection to process ping, pong and close
+// messages sent from the peer. If the application is not otherwise interested
+// in messages from the peer, then the application should start a goroutine to
+// read and discard messages from the peer. A simple example is:
+//
+//  func readLoop(c *websocket.Conn) {
+//      for {
+//          if _, _, err := c.NextReader(); err != nil {
+//              c.Close()
+//              break
+//          }
+//      }
+//  }
+//
+// Concurrency
+//
+// Connections support one concurrent reader and one concurrent writer.
+//
+// Applications are responsible for ensuring that no more than one goroutine
+// calls the write methods (NextWriter, SetWriteDeadline, WriteMessage,
+// WriteJSON) concurrently and that no more than one goroutine calls the read
+// methods (NextReader, SetReadDeadline, ReadMessage, ReadJSON, SetPongHandler,
+// SetPingHandler) concurrently.
+//
+// The Close and WriteControl methods can be called concurrently with all other
+// methods.
+//
+// Origin Considerations
+//
+// Web browsers allow Javascript applications to open a WebSocket connection to
+// any host. It's up to the server to enforce an origin policy using the Origin
+// request header sent by the browser.
+//
+// The Upgrader calls the function specified in the CheckOrigin field to check
+// the origin. If the CheckOrigin function returns false, then the Upgrade
+// method fails the WebSocket handshake with HTTP status 403.
+//
+// If the CheckOrigin field is nil, then the Upgrader uses a safe default: fail
+// the handshake if the Origin request header is present and not equal to the
+// Host request header.
+//
+// An application can allow connections from any origin by specifying a
+// function that always returns true:
+//
+//  var upgrader = websocket.Upgrader{
+//      CheckOrigin: func(r *http.Request) bool { return true },
+//  }
+//
+// The deprecated Upgrade function does not enforce an origin policy. It's the
+// application's responsibility to check the Origin header before calling
+// Upgrade.
+package websocket

vendor/github.com/gorilla/websocket/json.go

@@ -0,0 +1,55 @@
+// Copyright 2013 The Gorilla WebSocket Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package websocket
+
+import (
+	"encoding/json"
+	"io"
+)
+
+// WriteJSON is deprecated, use c.WriteJSON instead.
+func WriteJSON(c *Conn, v interface{}) error {
+	return c.WriteJSON(v)
+}
+
+// WriteJSON writes the JSON encoding of v to the connection.
+//
+// See the documentation for encoding/json Marshal for details about the
+// conversion of Go values to JSON.
+func (c *Conn) WriteJSON(v interface{}) error {
+	w, err := c.NextWriter(TextMessage)
+	if err != nil {
+		return err
+	}
+	err1 := json.NewEncoder(w).Encode(v)
+	err2 := w.Close()
+	if err1 != nil {
+		return err1
+	}
+	return err2
+}
+
+// ReadJSON is deprecated, use c.ReadJSON instead.
+func ReadJSON(c *Conn, v interface{}) error {
+	return c.ReadJSON(v)
+}
+
+// ReadJSON reads the next JSON-encoded message from the connection and stores
+// it in the value pointed to by v.
+//
+// See the documentation for the encoding/json Unmarshal function for details
+// about the conversion of JSON to a Go value.
+func (c *Conn) ReadJSON(v interface{}) error {
+	_, r, err := c.NextReader()
+	if err != nil {
+		return err
+	}
+	err = json.NewDecoder(r).Decode(v)
+	if err == io.EOF {
+		// One value is expected in the message.
+		err = io.ErrUnexpectedEOF
+	}
+	return err
+}

vendor/github.com/gorilla/websocket/server.go

@@ -0,0 +1,260 @@
+// Copyright 2013 The Gorilla WebSocket Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package websocket
+
+import (
+	"bufio"
+	"errors"
+	"net"
+	"net/http"
+	"net/url"
+	"strings"
+	"time"
+)
+
+// HandshakeError describes an error with the handshake from the peer.
+type HandshakeError struct {
+	message string
+}
+
+func (e HandshakeError) Error() string { return e.message }
+
+// Upgrader specifies parameters for upgrading an HTTP connection to a
+// WebSocket connection.
+type Upgrader struct {
+	// HandshakeTimeout specifies the duration for the handshake to complete.
+	HandshakeTimeout time.Duration
+
+	// ReadBufferSize and WriteBufferSize specify I/O buffer sizes. If a buffer
+	// size is zero, then a default value of 4096 is used. The I/O buffer sizes
+	// do not limit the size of the messages that can be sent or received.
+	ReadBufferSize, WriteBufferSize int
+
+	// Subprotocols specifies the server's supported protocols in order of
+	// preference. If this field is set, then the Upgrade method negotiates a
+	// subprotocol by selecting the first match in this list with a protocol
+	// requested by the client.
+	Subprotocols []string
+
+	// Error specifies the function for generating HTTP error responses. If Error
+	// is nil, then http.Error is used to generate the HTTP response.
+	Error func(w http.ResponseWriter, r *http.Request, status int, reason error)
+
+	// CheckOrigin returns true if the request Origin header is acceptable. If
+	// CheckOrigin is nil, the host in the Origin header must not be set or
+	// must match the host of the request.
+	CheckOrigin func(r *http.Request) bool
+}
+
+func (u *Upgrader) returnError(w http.ResponseWriter, r *http.Request, status int, reason string) (*Conn, error) {
+	err := HandshakeError{reason}
+	if u.Error != nil {
+		u.Error(w, r, status, err)
+	} else {
+		http.Error(w, http.StatusText(status), status)
+	}
+	return nil, err
+}
+
+// checkSameOrigin returns true if the origin is not set or is equal to the request host.
+func checkSameOrigin(r *http.Request) bool {
+	origin := r.Header["Origin"]
+	if len(origin) == 0 {
+		return true
+	}
+	u, err := url.Parse(origin[0])
+	if err != nil {
+		return false
+	}
+	return u.Host == r.Host
+}
+
+func (u *Upgrader) selectSubprotocol(r *http.Request, responseHeader http.Header) string {
+	if u.Subprotocols != nil {
+		clientProtocols := Subprotocols(r)
+		for _, serverProtocol := range u.Subprotocols {
+			for _, clientProtocol := range clientProtocols {
+				if clientProtocol == serverProtocol {
+					return clientProtocol
+				}
+			}
+		}
+	} else if responseHeader != nil {
+		return responseHeader.Get("Sec-Websocket-Protocol")
+	}
+	return ""
+}
+
+// Upgrade upgrades the HTTP server connection to the WebSocket protocol.
+//
+// The responseHeader is included in the response to the client's upgrade
+// request. Use the responseHeader to specify cookies (Set-Cookie) and the
+// application negotiated subprotocol (Sec-Websocket-Protocol).
+//
+// If the upgrade fails, then Upgrade replies to the client with an HTTP error
+// response.
+func (u *Upgrader) Upgrade(w http.ResponseWriter, r *http.Request, responseHeader http.Header) (*Conn, error) {
+	if r.Method != "GET" {
+		return u.returnError(w, r, http.StatusMethodNotAllowed, "websocket: method not GET")
+	}
+	if values := r.Header["Sec-Websocket-Version"]; len(values) == 0 || values[0] != "13" {
+		return u.returnError(w, r, http.StatusBadRequest, "websocket: version != 13")
+	}
+
+	if !tokenListContainsValue(r.Header, "Connection", "upgrade") {
+		return u.returnError(w, r, http.StatusBadRequest, "websocket: could not find connection header with token 'upgrade'")
+	}
+
+	if !tokenListContainsValue(r.Header, "Upgrade", "websocket") {
+		return u.returnError(w, r, http.StatusBadRequest, "websocket: could not find upgrade header with token 'websocket'")
+	}
+
+	checkOrigin := u.CheckOrigin
+	if checkOrigin == nil {
+		checkOrigin = checkSameOrigin
+	}
+	if !checkOrigin(r) {
+		return u.returnError(w, r, http.StatusForbidden, "websocket: origin not allowed")
+	}
+
+	challengeKey := r.Header.Get("Sec-Websocket-Key")
+	if challengeKey == "" {
+		return u.returnError(w, r, http.StatusBadRequest, "websocket: key missing or blank")
+	}
+
+	subprotocol := u.selectSubprotocol(r, responseHeader)
+
+	var (
+		netConn net.Conn
+		br      *bufio.Reader
+		err     error
+	)
+
+	h, ok := w.(http.Hijacker)
+	if !ok {
+		return u.returnError(w, r, http.StatusInternalServerError, "websocket: response does not implement http.Hijacker")
+	}
+	var rw *bufio.ReadWriter
+	netConn, rw, err = h.Hijack()
+	if err != nil {
+		return u.returnError(w, r, http.StatusInternalServerError, err.Error())
+	}
+	br = rw.Reader
+
+	if br.Buffered() > 0 {
+		netConn.Close()
+		return nil, errors.New("websocket: client sent data before handshake is complete")
+	}
+
+	c := newConn(netConn, true, u.ReadBufferSize, u.WriteBufferSize)
+	c.subprotocol = subprotocol
+
+	p := c.writeBuf[:0]
+	p = append(p, "HTTP/1.1 101 Switching Protocols\r\nUpgrade: websocket\r\nConnection: Upgrade\r\nSec-WebSocket-Accept: "...)
+	p = append(p, computeAcceptKey(challengeKey)...)
+	p = append(p, "\r\n"...)
+	if c.subprotocol != "" {
+		p = append(p, "Sec-Websocket-Protocol: "...)
+		p = append(p, c.subprotocol...)
+		p = append(p, "\r\n"...)
+	}
+	for k, vs := range responseHeader {
+		if k == "Sec-Websocket-Protocol" {
+			continue
+		}
+		for _, v := range vs {
+			p = append(p, k...)
+			p = append(p, ": "...)
+			for i := 0; i < len(v); i++ {
+				b := v[i]
+				if b <= 31 {
+					// prevent response splitting.
+					b = ' '
+				}
+				p = append(p, b)
+			}
+			p = append(p, "\r\n"...)
+		}
+	}
+	p = append(p, "\r\n"...)
+
+	// Clear deadlines set by HTTP server.
+	netConn.SetDeadline(time.Time{})
+
+	if u.HandshakeTimeout > 0 {
+		netConn.SetWriteDeadline(time.Now().Add(u.HandshakeTimeout))
+	}
+	if _, err = netConn.Write(p); err != nil {
+		netConn.Close()
+		return nil, err
+	}
+	if u.HandshakeTimeout > 0 {
+		netConn.SetWriteDeadline(time.Time{})
+	}
+
+	return c, nil
+}
+
+// Upgrade upgrades the HTTP server connection to the WebSocket protocol.
+//
+// This function is deprecated, use websocket.Upgrader instead.
+//
+// The application is responsible for checking the request origin before
+// calling Upgrade. An example implementation of the same origin policy is:
+//
+//	if req.Header.Get("Origin") != "http://"+req.Host {
+//		http.Error(w, "Origin not allowed", 403)
+//		return
+//	}
+//
+// If the endpoint supports subprotocols, then the application is responsible
+// for negotiating the protocol used on the connection. Use the Subprotocols()
+// function to get the subprotocols requested by the client. Use the
+// Sec-Websocket-Protocol response header to specify the subprotocol selected
+// by the application.
+//
+// The responseHeader is included in the response to the client's upgrade
+// request. Use the responseHeader to specify cookies (Set-Cookie) and the
+// negotiated subprotocol (Sec-Websocket-Protocol).
+//
+// The connection buffers IO to the underlying network connection. The
+// readBufSize and writeBufSize parameters specify the size of the buffers to
+// use. Messages can be larger than the buffers.
+//
+// If the request is not a valid WebSocket handshake, then Upgrade returns an
+// error of type HandshakeError. Applications should handle this error by
+// replying to the client with an HTTP error response.
+func Upgrade(w http.ResponseWriter, r *http.Request, responseHeader http.Header, readBufSize, writeBufSize int) (*Conn, error) {
+	u := Upgrader{ReadBufferSize: readBufSize, WriteBufferSize: writeBufSize}
+	u.Error = func(w http.ResponseWriter, r *http.Request, status int, reason error) {
+		// don't return errors to maintain backwards compatibility
+	}
+	u.CheckOrigin = func(r *http.Request) bool {
+		// allow all connections by default
+		return true
+	}
+	return u.Upgrade(w, r, responseHeader)
+}
+
+// Subprotocols returns the subprotocols requested by the client in the
+// Sec-Websocket-Protocol header.
+func Subprotocols(r *http.Request) []string {
+	h := strings.TrimSpace(r.Header.Get("Sec-Websocket-Protocol"))
+	if h == "" {
+		return nil
+	}
+	protocols := strings.Split(h, ",")
+	for i := range protocols {
+		protocols[i] = strings.TrimSpace(protocols[i])
+	}
+	return protocols
+}
+
+// IsWebSocketUpgrade returns true if the client requested upgrade to the
+// WebSocket protocol.
+func IsWebSocketUpgrade(r *http.Request) bool {
+	return tokenListContainsValue(r.Header, "Connection", "upgrade") &&
+		tokenListContainsValue(r.Header, "Upgrade", "websocket")
+}

vendor/github.com/gorilla/websocket/util.go

@@ -0,0 +1,44 @@
+// Copyright 2013 The Gorilla WebSocket Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package websocket
+
+import (
+	"crypto/rand"
+	"crypto/sha1"
+	"encoding/base64"
+	"io"
+	"net/http"
+	"strings"
+)
+
+// tokenListContainsValue returns true if the 1#token header with the given
+// name contains token.
+func tokenListContainsValue(header http.Header, name string, value string) bool {
+	for _, v := range header[name] {
+		for _, s := range strings.Split(v, ",") {
+			if strings.EqualFold(value, strings.TrimSpace(s)) {
+				return true
+			}
+		}
+	}
+	return false
+}
+
+var keyGUID = []byte("258EAFA5-E914-47DA-95CA-C5AB0DC85B11")
+
+func computeAcceptKey(challengeKey string) string {
+	h := sha1.New()
+	h.Write([]byte(challengeKey))
+	h.Write(keyGUID)
+	return base64.StdEncoding.EncodeToString(h.Sum(nil))
+}
+
+func generateChallengeKey() (string, error) {
+	p := make([]byte, 16)
+	if _, err := io.ReadFull(rand.Reader, p); err != nil {
+		return "", err
+	}
+	return base64.StdEncoding.EncodeToString(p), nil
+}