Upgrading server dependancies (#6215)

vendor/github.com/prometheus/common/route/route.go

@@ -1,26 +1,12 @@
 package route
 
 import (
-	"fmt"
 	"net/http"
-	"sync"
 
 	"github.com/julienschmidt/httprouter"
 	"golang.org/x/net/context"
 )
 
-var (
-	mtx   = sync.RWMutex{}
-	ctxts = map[*http.Request]context.Context{}
-)
-
-// Context returns the context for the request.
-func Context(r *http.Request) context.Context {
-	mtx.RLock()
-	defer mtx.RUnlock()
-	return ctxts[r]
-}
-
 type param string
 
 // Param returns param p for the context.
@@ -33,59 +19,35 @@ func WithParam(ctx context.Context, p, v string) context.Context {
 	return context.WithValue(ctx, param(p), v)
 }
 
-// ContextFunc returns a new context for a request.
-type ContextFunc func(r *http.Request) (context.Context, error)
-
 // Router wraps httprouter.Router and adds support for prefixed sub-routers
 // and per-request context injections.
 type Router struct {
 	rtr    *httprouter.Router
 	prefix string
-	ctxFn  ContextFunc
 }
 
 // New returns a new Router.
-func New(ctxFn ContextFunc) *Router {
-	if ctxFn == nil {
-		ctxFn = func(r *http.Request) (context.Context, error) {
-			return context.Background(), nil
-		}
-	}
+func New() *Router {
 	return &Router{
-		rtr:   httprouter.New(),
-		ctxFn: ctxFn,
+		rtr: httprouter.New(),
 	}
 }
 
 // WithPrefix returns a router that prefixes all registered routes with prefix.
 func (r *Router) WithPrefix(prefix string) *Router {
-	return &Router{rtr: r.rtr, prefix: r.prefix + prefix, ctxFn: r.ctxFn}
+	return &Router{rtr: r.rtr, prefix: r.prefix + prefix}
 }
 
 // handle turns a HandlerFunc into an httprouter.Handle.
 func (r *Router) handle(h http.HandlerFunc) httprouter.Handle {
 	return func(w http.ResponseWriter, req *http.Request, params httprouter.Params) {
-		reqCtx, err := r.ctxFn(req)
-		if err != nil {
-			http.Error(w, fmt.Sprintf("Error creating request context: %v", err), http.StatusBadRequest)
-			return
-		}
-		ctx, cancel := context.WithCancel(reqCtx)
+		ctx, cancel := context.WithCancel(req.Context())
 		defer cancel()
 
 		for _, p := range params {
 			ctx = context.WithValue(ctx, param(p.Key), p.Value)
 		}
-
-		mtx.Lock()
-		ctxts[req] = ctx
-		mtx.Unlock()
-
-		h(w, req)
-
-		mtx.Lock()
-		delete(ctxts, req)
-		mtx.Unlock()
+		h(w, req.WithContext(ctx))
 	}
 }
 
@@ -132,7 +94,7 @@ func FileServe(dir string) http.HandlerFunc {
 	fs := http.FileServer(http.Dir(dir))
 
 	return func(w http.ResponseWriter, r *http.Request) {
-		r.URL.Path = Param(Context(r), "filepath")
+		r.URL.Path = Param(r.Context(), "filepath")
 		fs.ServeHTTP(w, r)
 	}
 }