[ws-proxy] Don't leak workspace info Go routines

Author: Christian Weichel

components/ws-proxy/pkg/proxy/infoprovider.go

@@ -275,8 +275,15 @@ func mapWorkspaceStatusToInfo(status *wsapi.WorkspaceStatus) *WorkspaceInfo {
 	}
 }
 
-// WorkspaceInfo return the WorkspaceInfo avaiable for the given workspaceID
+// WorkspaceInfo return the WorkspaceInfo avaiable for the given workspaceID.
+// Callers should make sure their context gets canceled properly. For good measure
+// this function will timeout by itself as well.
 func (p *RemoteWorkspaceInfoProvider) WorkspaceInfo(ctx context.Context, workspaceID string) *WorkspaceInfo {
+	// In case the parent context does not cancel for some reason, we want to make sure
+	// we clean up after ourselves to not leak Go routines.
+	ctx, cancel := context.WithTimeout(ctx, 5*time.Second)
+	defer cancel()
+
 	info, present := p.cache.WaitFor(ctx, workspaceID)
 	if !present {
 		return nil

components/ws-proxy/pkg/proxy/routes.go

@@ -482,10 +482,7 @@ func workspaceMustExistHandler(config *Config, infoProvider WorkspaceInfoProvide
 	return func(h http.Handler) http.Handler {
 		return http.HandlerFunc(func(resp http.ResponseWriter, req *http.Request) {
 			coords := getWorkspaceCoords(req)
-			// it might take some time until the event comes in. Let's wait for it at most 3 secs.
-			ctx, cancel := context.WithTimeout(req.Context(), 3*time.Second)
-			defer cancel()
-			info := infoProvider.WorkspaceInfo(ctx, coords.ID)
+			info := infoProvider.WorkspaceInfo(req.Context(), coords.ID)
 			if info == nil {
 				log.WithFields(log.OWI("", coords.ID, "")).Info("no workspace info found - redirecting to start")
 				redirectURL := fmt.Sprintf("%s://%s/start/#%s", config.GitpodInstallation.Scheme, config.GitpodInstallation.HostName, coords.ID)