testing: add method to notify containers through a channel

Related to issue #105.

testing/server.go

@@ -43,6 +43,7 @@ type DockerServer struct {
 	mux        *mux.Router
 	hook       func(*http.Request)
 	failures   map[string]FailureSpec
+	cChan      chan<- *docker.Container
 }
 
 // FailureSpec is used with PrepareFailure and describes in which situations
@@ -58,19 +59,36 @@ type FailureSpec struct {
 // the method URL to get the URL of the server.
 //
 // It receives the bind address (use 127.0.0.1:0 for getting an available port
-// on the host) and a hook function, that will be called on every request.
-func NewServer(bind string, hook func(*http.Request)) (*DockerServer, error) {
+// on the host), a channel of containers and a hook function, that will be
+// called on every request.
+//
+// The fake server will send containers in the channel whenever the container
+// changes its state, via the HTTP API (i.e.: create, start and stop). This
+// channel may be nil, which means that the server won't notify on state
+// changes.
+func NewServer(bind string, containerChan chan<- *docker.Container, hook func(*http.Request)) (*DockerServer, error) {
 	listener, err := net.Listen("tcp", bind)
 	if err != nil {
 		return nil, err
 	}
-	server := DockerServer{listener: listener, imgIDs: make(map[string]string), hook: hook,
-		failures: make(map[string]FailureSpec)}
+	server := DockerServer{
+		listener: listener,
+		imgIDs:   make(map[string]string),
+		hook:     hook,
+		failures: make(map[string]FailureSpec),
+		cChan:    containerChan,
+	}
 	server.buildMuxer()
 	go http.Serve(listener, &server)
 	return &server, nil
 }
 
+func (s *DockerServer) notify(container *docker.Container) {
+	if s.cChan != nil {
+		s.cChan <- container
+	}
+}
+
 func (s *DockerServer) buildMuxer() {
 	s.mux = mux.NewRouter()
 	s.mux.Path("/commit").Methods("POST").HandlerFunc(s.handlerWrapper(s.commitContainer))
@@ -284,6 +302,7 @@ func (s *DockerServer) createContainer(w http.ResponseWriter, r *http.Request) {
 	s.cMut.Lock()
 	s.containers = append(s.containers, &container)
 	s.cMut.Unlock()
+	s.notify(&container)
 	var c = struct{ ID string }{ID: container.ID}
 	json.NewEncoder(w).Encode(c)
 }
@@ -320,6 +339,7 @@ func (s *DockerServer) startContainer(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 	container.State.Running = true
+	s.notify(container)
 }
 
 func (s *DockerServer) stopContainer(w http.ResponseWriter, r *http.Request) {
@@ -337,6 +357,7 @@ func (s *DockerServer) stopContainer(w http.ResponseWriter, r *http.Request) {
 	}
 	w.WriteHeader(http.StatusNoContent)
 	container.State.Running = false
+	s.notify(container)
 }
 
 func (s *DockerServer) attachContainer(w http.ResponseWriter, r *http.Request) {

testing/server_test.go

@@ -20,7 +20,7 @@ import (
 )
 
 func TestNewServer(t *testing.T) {
-	server, err := NewServer("127.0.0.1:0", nil)
+	server, err := NewServer("127.0.0.1:0", nil, nil)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -33,7 +33,7 @@ func TestNewServer(t *testing.T) {
 }
 
 func TestServerStop(t *testing.T) {
-	server, err := NewServer("127.0.0.1:0", nil)
+	server, err := NewServer("127.0.0.1:0", nil, nil)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -50,7 +50,7 @@ func TestServerStopNoListener(t *testing.T) {
 }
 
 func TestServerURL(t *testing.T) {
-	server, err := NewServer("127.0.0.1:0", nil)
+	server, err := NewServer("127.0.0.1:0", nil, nil)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -71,7 +71,7 @@ func TestServerURLNoListener(t *testing.T) {
 
 func TestHandleWithHook(t *testing.T) {
 	var called bool
-	server, _ := NewServer("127.0.0.1:0", func(*http.Request) { called = true })
+	server, _ := NewServer("127.0.0.1:0", nil, func(*http.Request) { called = true })
 	defer server.Stop()
 	recorder := httptest.NewRecorder()
 	request, _ := http.NewRequest("GET", "/containers/json?all=1", nil)
@@ -158,6 +158,25 @@ func TestCreateContainer(t *testing.T) {
 	}
 }
 
+func TestCreateContainerWithNotifyChannel(t *testing.T) {
+	ch := make(chan *docker.Container, 1)
+	server := DockerServer{}
+	server.imgIDs = map[string]string{"base": "a1234"}
+	server.cChan = ch
+	server.buildMuxer()
+	recorder := httptest.NewRecorder()
+	body := `{"Hostname":"", "User":"", "Memory":0, "MemorySwap":0, "AttachStdin":false, "AttachStdout":true, "AttachStderr":true,
+"PortSpecs":null, "Tty":false, "OpenStdin":false, "StdinOnce":false, "Env":null, "Cmd":["date"], "Image":"base", "Volumes":{}, "VolumesFrom":""}`
+	request, _ := http.NewRequest("POST", "/containers/create", strings.NewReader(body))
+	server.ServeHTTP(recorder, request)
+	if recorder.Code != http.StatusCreated {
+		t.Errorf("CreateContainer: wrong status. Want %d. Got %d.", http.StatusCreated, recorder.Code)
+	}
+	if notified := <-ch; notified != server.containers[0] {
+		t.Errorf("CreateContainer: did not notify the proper container. Want %q. Got %q.", server.containers[0].ID, notified.ID)
+	}
+}
+
 func TestCreateContainerInvalidBody(t *testing.T) {
 	server := DockerServer{}
 	server.buildMuxer()
@@ -320,6 +339,25 @@ func TestStartContainer(t *testing.T) {
 	}
 }
 
+func TestStartContainerWithNotifyChannel(t *testing.T) {
+	ch := make(chan *docker.Container, 1)
+	server := DockerServer{}
+	server.cChan = ch
+	addContainers(&server, 1)
+	addContainers(&server, 1)
+	server.buildMuxer()
+	recorder := httptest.NewRecorder()
+	path := fmt.Sprintf("/containers/%s/start", server.containers[1].ID)
+	request, _ := http.NewRequest("POST", path, nil)
+	server.ServeHTTP(recorder, request)
+	if recorder.Code != http.StatusOK {
+		t.Errorf("StartContainer: wrong status code. Want %d. Got %d.", http.StatusOK, recorder.Code)
+	}
+	if notified := <-ch; notified != server.containers[1] {
+		t.Errorf("StartContainer: did not notify the proper container. Want %q. Got %q.", server.containers[1].ID, notified.ID)
+	}
+}
+
 func TestStartContainerNotFound(t *testing.T) {
 	server := DockerServer{}
 	server.buildMuxer()
@@ -363,6 +401,26 @@ func TestStopContainer(t *testing.T) {
 	}
 }
 
+func TestStopContainerWithNotifyChannel(t *testing.T) {
+	ch := make(chan *docker.Container, 1)
+	server := DockerServer{}
+	server.cChan = ch
+	addContainers(&server, 1)
+	addContainers(&server, 1)
+	server.containers[1].State.Running = true
+	server.buildMuxer()
+	recorder := httptest.NewRecorder()
+	path := fmt.Sprintf("/containers/%s/stop", server.containers[1].ID)
+	request, _ := http.NewRequest("POST", path, nil)
+	server.ServeHTTP(recorder, request)
+	if recorder.Code != http.StatusNoContent {
+		t.Errorf("StopContainer: wrong status code. Want %d. Got %d.", http.StatusNoContent, recorder.Code)
+	}
+	if notified := <-ch; notified != server.containers[1] {
+		t.Errorf("StopContainer: did not notify the proper container. Want %q. Got %q.", server.containers[1].ID, notified.ID)
+	}
+}
+
 func TestStopContainerNotFound(t *testing.T) {
 	server := DockerServer{}
 	server.buildMuxer()