docker: make the setup work locally for dev.

Also don't error when the websocket is closed.

Author: Edward Muller

Dockerfile

@@ -1 +1,15 @@
-FROM heroku/go:latest
+FROM heroku/cedar:14
+MAINTAINER Heroku Build & Packaging Team <build-and-packaging@heroku.com>
+
+COPY . /app/src/github.com/heroku-examples/go-websocket-chat-demo
+WORKDIR /app/src/github.com/heroku-examples/go-websocket-chat-demo
+
+ENV HOME /app
+ENV GOVERSION=1.8
+ENV GOROOT $HOME/.go/$GOVERSION/go
+ENV GOPATH $HOME
+ENV PATH $PATH:$HOME/bin:$GOROOT/bin:$GOPATH/bin
+
+RUN mkdir -p $HOME/.go/$GOVERSION
+RUN cd $HOME/.go/$GOVERSION; curl -s https://storage.googleapis.com/golang/go$GOVERSION.linux-amd64.tar.gz | tar zxf -
+RUN go install -v github.com/heroku-examples/go-websocket-chat-demo

app.json

@@ -4,10 +4,9 @@
   "keywords": [
     "streaming",
     "redis",
-    "go"
+    "go",
+    "websocket"
   ],
-  "image": "heroku/go:latest",
-  "mount_dir": "src/github.com/heroku-examples/go-websocket-chat-demo",
   "website": "http://github.com/heroku-examples/go-websocket-chat-demo",
   "repository": "http://github.com/heroku-examples/go-websocket-chat-demol",
   "addons": [

chat.go

@@ -60,12 +60,11 @@ func handleWebsocket(w http.ResponseWriter, r *http.Request) {
 		mt, data, err := ws.ReadMessage()
 		l := log.WithFields(logrus.Fields{"mt": mt, "data": data, "err": err})
 		if err != nil {
-			if err == io.EOF {
+			if websocket.IsCloseError(err, websocket.CloseGoingAway) || err == io.EOF {
 				l.Info("Websocket closed!")
-			} else {
-				l.Error("Error reading websocket message")
+				break
 			}
-			break
+			l.Error("Error reading websocket message")
 		}
 		switch mt {
 		case websocket.TextMessage:

docker-compose.yml

@@ -1,26 +1,18 @@
-web:
-  build: .
-  command: 'bash -c ''go-websocket-chat-demo-web'''
-  working_dir: /app/user/src/github.com/heroku-examples/go-websocket-chat-demo
-  environment:
-    PORT: 8080
-    REDIS_URL: 'redis://herokuRedis:6379'
-  ports:
-    - '8080:8080'
-  links:
-    - herokuRedis
-shell:
-  build: .
-  command: bash
-  working_dir: /app/user/src/github.com/heroku-examples/go-websocket-chat-demo
-  environment:
-    PORT: 8080
-    REDIS_URL: 'redis://herokuRedis:6379'
-  ports:
-    - '8080:8080'
-  links:
-    - herokuRedis
-  volumes:
-    - '.:/app/user/src/github.com/heroku-examples/go-websocket-chat-demo'
-herokuRedis:
-  image: redis
+version: '2'
+
+services:
+  app:
+    command: go-websocket-chat-demo
+    build: .
+    environment:
+      PORT: '5000'
+      REDIS_URL: 'redis://redis:6379'
+    depends_on:
+      - redis
+    ports:
+      - "127.0.0.1:5000:5000"
+
+  redis:
+    image: redis
+    ports:
+      - "6379:6379"