partial fix for UI

api/command_echo.go

@@ -0,0 +1,81 @@
+// Copyright (c) 2016 Mattermost, Inc. All Rights Reserved.
+// See License.txt for license information.
+
+package api
+
+import (
+	"strconv"
+	"strings"
+	"time"
+
+	l4g "code.google.com/p/log4go"
+	"github.com/mattermost/platform/model"
+)
+
+var echoSem chan bool
+
+type EchoProvider struct {
+}
+
+func init() {
+	RegisterCommandProvider(&EchoProvider{})
+}
+
+func (me *EchoProvider) GetCommand() *model.Command {
+	return &model.Command{
+		Trigger:          "echo",
+		AutoComplete:     true,
+		AutoCompleteDesc: "Echo back text from your account",
+		AutoCompleteHint: "\"message\" [delay in seconds]",
+		DisplayName:      "echo",
+	}
+}
+
+func (me *EchoProvider) DoCommand(c *Context, channelId string, message string) *model.CommandResponse {
+	maxThreads := 100
+
+	delay := 0
+	if endMsg := strings.LastIndex(message, "\""); string(message[0]) == "\"" && endMsg > 1 {
+		if checkDelay, err := strconv.Atoi(strings.Trim(message[endMsg:], " \"")); err == nil {
+			delay = checkDelay
+		}
+		message = message[1:endMsg]
+	} else if strings.Index(message, " ") > -1 {
+		delayIdx := strings.LastIndex(message, " ")
+		delayStr := strings.Trim(message[delayIdx:], " ")
+
+		if checkDelay, err := strconv.Atoi(delayStr); err == nil {
+			delay = checkDelay
+			message = message[:delayIdx]
+		}
+	}
+
+	if delay > 10000 {
+		return &model.CommandResponse{Text: "Delays must be under 10000 seconds", ResponseType: model.COMMAND_RESPONSE_TYPE_EPHEMERAL}
+	}
+
+	if echoSem == nil {
+		// We want one additional thread allowed so we never reach channel lockup
+		echoSem = make(chan bool, maxThreads+1)
+	}
+
+	if len(echoSem) >= maxThreads {
+		return &model.CommandResponse{Text: "High volume of echo request, cannot process request", ResponseType: model.COMMAND_RESPONSE_TYPE_EPHEMERAL}
+	}
+
+	echoSem <- true
+	go func() {
+		defer func() { <-echoSem }()
+		post := &model.Post{}
+		post.ChannelId = channelId
+		post.Message = message
+
+		time.Sleep(time.Duration(delay) * time.Second)
+
+		if _, err := CreatePost(c, post, true); err != nil {
+			l4g.Error("Unable to create /echo post, err=%v", err)
+		}
+	}()
+
+	return &model.CommandResponse{}
+}