Added endpoint to proxy connections to runner builds

In this MR we add two endpoints for proxying requests
to services running inside the runner's builds.

One of the endpoints is for regular HTTP requests, while
the other is for websockets.

channel_test.go

@@ -20,8 +20,9 @@ import (
 )
 
 var (
-	envTerminalPath = fmt.Sprintf("%s/environments/1/terminal.ws", testProject)
-	jobTerminalPath = fmt.Sprintf("%s/-/jobs/1/terminal.ws", testProject)
+	envTerminalPath     = fmt.Sprintf("%s/environments/1/terminal.ws", testProject)
+	jobTerminalPath     = fmt.Sprintf("%s/-/jobs/1/terminal.ws", testProject)
+	servicesProxyWSPath = fmt.Sprintf("%s/-/jobs/1/proxy.ws", testProject)
 )
 
 type connWithReq struct {
@@ -36,6 +37,7 @@ func TestChannelHappyPath(t *testing.T) {
 	}{
 		{"environments", envTerminalPath},
 		{"jobs", jobTerminalPath},
+		{"services", servicesProxyWSPath},
 	}
 	for _, test := range tests {
 		t.Run(test.name, func(t *testing.T) {
@@ -74,15 +76,16 @@ func TestChannelHappyPath(t *testing.T) {
 
 func TestChannelHappyPathWithTerminalResponse(t *testing.T) {
 	tests := []struct {
-		name         string
-		terminalPath string
+		name        string
+		channelPath string
 	}{
 		{"environments", envTerminalPath},
 		{"jobs", jobTerminalPath},
+		{"services", servicesProxyWSPath},
 	}
 	for _, test := range tests {
 		t.Run(test.name, func(t *testing.T) {
-			serverConns, clientURL, close := wireupTerminal(test.terminalPath, nil, "channel.k8s.io")
+			serverConns, clientURL, close := wireupTerminal(test.channelPath, nil, "channel.k8s.io")
 			defer close()
 
 			client, _, err := dialWebsocket(clientURL, nil, "terminal.gitlab.com")

internal/upstream/routes.go

@@ -190,6 +190,9 @@ func (u *upstream) configureRoutes() {
 		wsRoute(projectPattern+`environments/[0-9]+/terminal.ws\z`, channel.Handler(api)),
 		wsRoute(projectPattern+`-/jobs/[0-9]+/terminal.ws\z`, channel.Handler(api)),
 
+		// Proxy Job Services
+		wsRoute(projectPattern+`-/jobs/[0-9]+/proxy.ws\z`, channel.Handler(api)),
+
 		// Long poll and limit capacity given to jobs/request and builds/register.json
 		route("", apiPattern+`v4/jobs/request\z`, ciAPILongPolling),
 		route("", ciAPIPattern+`v1/builds/register.json\z`, ciAPILongPolling),