Add integration test for cable backend

Tests a single backend setup and a separate cable backend setup

cable_test.go

+package main
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"net/url"
+	"regexp"
+	"testing"
+
+	"github.com/gorilla/websocket"
+	"github.com/stretchr/testify/require"
+
+	"gitlab.com/gitlab-org/gitlab-workhorse/internal/config"
+	"gitlab.com/gitlab-org/gitlab-workhorse/internal/helper"
+	"gitlab.com/gitlab-org/gitlab-workhorse/internal/testhelper"
+)
+
+const cablePath = "/-/cable"
+
+func TestSingleBackend(t *testing.T) {
+	cableServerConns, cableBackendServer := startCableServer()
+	defer cableBackendServer.Close()
+
+	config := newUpstreamWithCableConfig(cableBackendServer.URL, "")
+	workhorse := startWorkhorseServerWithConfig(config)
+	defer workhorse.Close()
+
+	cableURL := websocketURL(workhorse.URL, cablePath)
+
+	client, _, err := dialWebsocket(cableURL, nil)
+	require.NoError(t, err)
+	defer client.Close()
+
+	server := (<-cableServerConns).conn
+	defer server.Close()
+
+	require.NoError(t, say(client, "hello"))
+	assertReadMessage(t, server, websocket.TextMessage, "hello")
+
+	require.NoError(t, say(server, "world"))
+	assertReadMessage(t, client, websocket.TextMessage, "world")
+}
+
+func TestSeparateCableBackend(t *testing.T) {
+	authBackendServer := testhelper.TestServerWithHandler(regexp.MustCompile(`.`), http.HandlerFunc(http.NotFound))
+	defer authBackendServer.Close()
+
+	cableServerConns, cableBackendServer := startCableServer()
+	defer cableBackendServer.Close()
+
+	config := newUpstreamWithCableConfig(authBackendServer.URL, cableBackendServer.URL)
+	workhorse := startWorkhorseServerWithConfig(config)
+	defer workhorse.Close()
+
+	cableURL := websocketURL(workhorse.URL, cablePath)
+
+	client, _, err := dialWebsocket(cableURL, nil)
+	require.NoError(t, err)
+	defer client.Close()
+
+	server := (<-cableServerConns).conn
+	defer server.Close()
+
+	require.NoError(t, say(client, "hello"))
+	assertReadMessage(t, server, websocket.TextMessage, "hello")
+
+	require.NoError(t, say(server, "world"))
+	assertReadMessage(t, client, websocket.TextMessage, "world")
+}
+
+func startCableServer() (chan connWithReq, *httptest.Server) {
+	upgrader := &websocket.Upgrader{}
+
+	connCh := make(chan connWithReq, 1)
+	server := testhelper.TestServerWithHandler(regexp.MustCompile(cablePath), webSocketHandler(upgrader, connCh))
+
+	return connCh, server
+}
+
+func newUpstreamWithCableConfig(authBackend string, cableBackend string) *config.Config {
+	var cableBackendURL *url.URL
+
+	if cableBackend != "" {
+		cableBackendURL = helper.URLMustParse(cableBackend)
+	}
+
+	return &config.Config{
+		Version:      "123",
+		DocumentRoot: testDocumentRoot,
+		Backend:      helper.URLMustParse(authBackend),
+		CableBackend: cableBackendURL,
+	}
+}

channel_test.go

@@ -171,7 +171,13 @@ func startWebsocketServer(subprotocols ...string) (chan connWithReq, *httptest.S
 	upgrader := &websocket.Upgrader{Subprotocols: subprotocols}
 
 	connCh := make(chan connWithReq, 1)
-	server := httptest.NewTLSServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+	server := httptest.NewTLSServer(webSocketHandler(upgrader, connCh))
+
+	return connCh, server
+}
+
+func webSocketHandler(upgrader *websocket.Upgrader, connCh chan connWithReq) http.HandlerFunc {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		logEntry := log.WithFields(log.Fields{
 			"method":  r.Method,
 			"url":     r.URL,
@@ -186,9 +192,7 @@ func startWebsocketServer(subprotocols ...string) (chan connWithReq, *httptest.S
 		}
 		connCh <- connWithReq{conn, r}
 		// The connection has been hijacked so it's OK to end here
-	}))
-
-	return connCh, server
+	})
 }
 
 func channelOkBody(remote *httptest.Server, header http.Header, subprotocols ...string) *api.Response {