Golang safe.NewBuffer函数代码示例

func (a *autoScaleConfig) removeNode(chosenNode *cluster.Node) error {
	_, hasIaas := chosenNode.Metadata["iaas"]
	if !hasIaas {
		return fmt.Errorf("no IaaS information in node (%s) metadata: %#v", chosenNode.Address, chosenNode.Metadata)
	}
	err := a.provisioner.getCluster().Unregister(chosenNode.Address)
	if err != nil {
		return fmt.Errorf("unable to unregister node (%s) for removal: %s", chosenNode.Address, err)
	}
	buf := safe.NewBuffer(nil)
	err = a.provisioner.moveContainers(urlToHost(chosenNode.Address), "", buf)
	if err != nil {
		a.provisioner.getCluster().Register(chosenNode.Address, chosenNode.Metadata)
		return fmt.Errorf("unable to move containers from node (%s): %s - log: %s", chosenNode.Address, err, buf.String())
	}
	m, err := iaas.FindMachineByIdOrAddress(chosenNode.Metadata["iaas-id"], urlToHost(chosenNode.Address))
	if err != nil {
		a.logError("unable to find machine for removal in iaas: %s", err)
		return nil
	}
	err = m.Destroy()
	if err != nil {
		a.logError("unable to destroy machine in IaaS: %s", err)
	}
	return nil
}

func (s *S) TestAppShellSpecifyUnit(c *check.C) {
	a := app.App{
		Name:     "someapp",
		Platform: "zend",
		Teams:    []string{s.team.Name},
	}
	err := s.conn.Apps().Insert(a)
	c.Assert(err, check.IsNil)
	defer s.conn.Apps().Remove(bson.M{"name": a.Name})
	defer s.logConn.Logs(a.Name).DropCollection()
	err = s.provisioner.Provision(&a)
	c.Assert(err, check.IsNil)
	defer s.provisioner.Destroy(&a)
	s.provisioner.AddUnits(&a, 5, "web", nil)
	unit := s.provisioner.Units(&a)[3]
	url := fmt.Sprintf("/shell?:app=%s&width=140&height=38&term=xterm&unit=%s", a.Name, unit.Name)
	request, err := http.NewRequest("GET", url, nil)
	c.Assert(err, check.IsNil)
	buf := safe.NewBuffer([]byte("echo teste"))
	recorder := provisiontest.Hijacker{Conn: &provisiontest.FakeConn{Buf: buf}}
	err = remoteShellHandler(&recorder, request, s.token)
	c.Assert(err, check.IsNil)
	shells := s.provisioner.Shells(unit.Name)
	c.Assert(shells, check.HasLen, 1)
	c.Assert(shells[0].App.GetName(), check.Equals, a.Name)
	c.Assert(shells[0].Width, check.Equals, 140)
	c.Assert(shells[0].Height, check.Equals, 38)
	c.Assert(shells[0].Term, check.Equals, "xterm")
	c.Assert(shells[0].Unit, check.Equals, unit.Name)
	for _, u := range s.provisioner.Units(&a) {
		if u.Name != unit.Name {
			c.Check(s.provisioner.Shells(u.Name), check.HasLen, 0)
		}
	}
}

func (s *S) TestEnsureContainersStartedOnlyChild(c *check.C) {
	err := nodecontainer.AddNewContainer("p1", &nodecontainer.NodeContainerConfig{
		Name: "c1",
		Config: docker.Config{
			Image: "myregistry/tsuru/bs",
		},
	})
	c.Assert(err, check.IsNil)
	p, err := dockertest.StartMultipleServersCluster()
	c.Assert(err, check.IsNil)
	defer p.Destroy()
	clust := p.Cluster()
	nodes, err := clust.Nodes()
	c.Assert(err, check.IsNil)
	c.Assert(nodes, check.HasLen, 2)
	nodes[0].Metadata["pool"] = "p1"
	_, err = p.Cluster().UpdateNode(nodes[0])
	c.Assert(err, check.IsNil)
	nodes[1].Metadata["pool"] = "p2"
	_, err = p.Cluster().UpdateNode(nodes[1])
	c.Assert(err, check.IsNil)
	buf := safe.NewBuffer(nil)
	err = ensureContainersStarted(p, buf, true, nil)
	c.Assert(err, check.IsNil)
	client, err := docker.NewClient(nodes[0].Address)
	c.Assert(err, check.IsNil)
	containers, err := client.ListContainers(docker.ListContainersOptions{All: true})
	c.Assert(err, check.IsNil)
	c.Assert(containers, check.HasLen, 1)
	client2, err := docker.NewClient(nodes[1].Address)
	c.Assert(err, check.IsNil)
	containers2, err := client2.ListContainers(docker.ListContainersOptions{All: true})
	c.Assert(err, check.IsNil)
	c.Assert(containers2, check.HasLen, 0)
}

func (s *HandlersSuite) TestSSHToContainerHandler(c *gocheck.C) {
	sshServer := newMockSSHServer(c, 2e9)
	defer sshServer.Shutdown()
	coll := collection()
	defer coll.Close()
	container := container{
		ID:          "9930c24f1c4x",
		AppName:     "makea",
		Type:        "python",
		Status:      provision.StatusStarted.String(),
		IP:          "127.0.0.4",
		HostPort:    "9025",
		HostAddr:    "localhost",
		SSHHostPort: sshServer.port,
		PrivateKey:  string(fakeServerPrivateKey),
		User:        sshUsername(),
	}
	err := coll.Insert(container)
	c.Assert(err, gocheck.IsNil)
	defer coll.RemoveAll(bson.M{"appname": "makea"})
	tmpDir, err := ioutil.TempDir("", "containerssh")
	defer os.RemoveAll(tmpDir)
	filepath := path.Join(tmpDir, "file.txt")
	file, err := os.Create(filepath)
	c.Assert(err, gocheck.IsNil)
	file.Write([]byte("hello"))
	file.Close()
	buf := safe.NewBuffer([]byte("cat " + filepath + "\nexit\n"))
	recorder := hijacker{conn: &fakeConn{buf}}
	request, err := http.NewRequest("GET", "/?:container_id="+container.ID, nil)
	c.Assert(err, gocheck.IsNil)
	err = sshToContainerHandler(&recorder, request, nil)
	c.Assert(err, gocheck.IsNil)
}

func (s *S) SetUpTest(c *check.C) {
	config.Set("docker:api-timeout", 2)
	iaas.ResetAll()
	repositorytest.Reset()
	queue.ResetQueue()
	repository.Manager().CreateUser(s.user.Email)
	s.p = &dockerProvisioner{storage: &cluster.MapStorage{}}
	err := s.p.Initialize()
	c.Assert(err, check.IsNil)
	queue.ResetQueue()
	s.server, err = dtesting.NewServer("127.0.0.1:0", nil, nil)
	c.Assert(err, check.IsNil)
	s.p.cluster, err = cluster.New(nil, s.p.storage,
		cluster.Node{Address: s.server.URL(), Metadata: map[string]string{"pool": "test-default"}},
	)
	c.Assert(err, check.IsNil)
	mainDockerProvisioner = s.p
	err = dbtest.ClearAllCollectionsExcept(s.storage.Apps().Database, []string{"users", "tokens", "teams"})
	c.Assert(err, check.IsNil)
	err = clearClusterStorage(s.clusterSess)
	c.Assert(err, check.IsNil)
	routertest.FakeRouter.Reset()
	opts := provision.AddPoolOptions{Name: "test-default", Default: true}
	err = provision.AddPool(opts)
	c.Assert(err, check.IsNil)
	s.storage.Tokens().Remove(bson.M{"appname": bson.M{"$ne": ""}})
	s.logBuf = safe.NewBuffer(nil)
	log.SetLogger(log.NewWriterLogger(s.logBuf, true))
	s.token = createTokenForUser(s.user, "*", string(permission.CtxGlobal), "", c)
}

func (s *S) TestFollowLogsAndCommitForward(c *check.C) {
	err := s.newFakeImage(s.p, "tsuru/python", nil)
	c.Assert(err, check.IsNil)
	app := provisiontest.NewFakeApp("mightyapp", "python", 1)
	nextImgName, err := appNewImageName(app.GetName())
	c.Assert(err, check.IsNil)
	cont := container.Container{AppName: "mightyapp", ID: "myid123", BuildingImage: nextImgName}
	err = cont.Create(&container.CreateArgs{
		App:         app,
		ImageID:     "tsuru/python",
		Commands:    []string{"foo"},
		Provisioner: s.p,
	})
	c.Assert(err, check.IsNil)
	buf := safe.NewBuffer(nil)
	args := runContainerActionsArgs{writer: buf, provisioner: s.p}
	context := action.FWContext{Params: []interface{}{args}, Previous: cont}
	imageId, err := followLogsAndCommit.Forward(context)
	c.Assert(err, check.IsNil)
	c.Assert(imageId, check.Equals, "tsuru/app-mightyapp:v1")
	c.Assert(buf.String(), check.Not(check.Equals), "")
	var dbCont container.Container
	coll := s.p.Collection()
	defer coll.Close()
	err = coll.Find(bson.M{"id": cont.ID}).One(&dbCont)
	c.Assert(err, check.NotNil)
	c.Assert(err.Error(), check.Equals, "not found")
	_, err = s.p.Cluster().InspectContainer(cont.ID)
	c.Assert(err, check.NotNil)
	c.Assert(err.Error(), check.Matches, "No such container.*")
	err = s.p.Cluster().RemoveImage("tsuru/app-mightyapp:v1")
	c.Assert(err, check.IsNil)
}

func (s *S) TestBindAndHealthcheckBackward(c *check.C) {
	appName := "my-fake-app"
	err := s.newFakeImage(s.p, "tsuru/app-"+appName, nil)
	c.Assert(err, check.IsNil)
	fakeApp := provisiontest.NewFakeApp(appName, "python", 0)
	s.p.Provision(fakeApp)
	defer s.p.Destroy(fakeApp)
	buf := safe.NewBuffer(nil)
	args := changeUnitsPipelineArgs{
		app:         fakeApp,
		provisioner: s.p,
		writer:      buf,
		toAdd:       map[string]*containersToAdd{"web": {Quantity: 2}},
		imageId:     "tsuru/app-" + appName,
	}
	containers, err := addContainersWithHost(&args)
	c.Assert(err, check.IsNil)
	c.Assert(containers, check.HasLen, 2)
	context := action.BWContext{Params: []interface{}{args}, FWResult: containers}
	for _, c := range containers {
		u := c.AsUnit(fakeApp)
		fakeApp.BindUnit(&u)
	}
	bindAndHealthcheck.Backward(context)
	c.Assert(err, check.IsNil)
	u1 := containers[0].AsUnit(fakeApp)
	c.Assert(fakeApp.HasBind(&u1), check.Equals, false)
	u2 := containers[1].AsUnit(fakeApp)
	c.Assert(fakeApp.HasBind(&u2), check.Equals, false)
}

func (s *S) TestMoveContainerErrorStarted(c *check.C) {
	p, err := s.startMultipleServersCluster()
	c.Assert(err, check.IsNil)
	err = s.newFakeImage(p, "tsuru/app-myapp", nil)
	c.Assert(err, check.IsNil)
	appInstance := provisiontest.NewFakeApp("myapp", "python", 0)
	p.Provision(appInstance)
	imageId, err := image.AppCurrentImageName(appInstance.GetName())
	c.Assert(err, check.IsNil)
	addedConts, err := addContainersWithHost(&changeUnitsPipelineArgs{
		toHost:      "localhost",
		toAdd:       map[string]*containersToAdd{"web": {Quantity: 2}},
		app:         appInstance,
		imageId:     imageId,
		provisioner: p,
	})
	c.Assert(err, check.IsNil)
	err = addedConts[0].SetStatus(p, provision.StatusError, true)
	c.Assert(err, check.IsNil)
	appStruct := &app.App{
		Name: appInstance.GetName(),
	}
	err = s.storage.Apps().Insert(appStruct)
	c.Assert(err, check.IsNil)
	buf := safe.NewBuffer(nil)
	_, err = p.moveContainer(addedConts[0].ID[:6], "127.0.0.1", buf)
	c.Assert(err, check.IsNil)
	containers, err := p.listContainersByHost("localhost")
	c.Assert(err, check.IsNil)
	c.Assert(containers, check.HasLen, 1)
	containers, err = p.listContainersByHost("127.0.0.1")
	c.Assert(err, check.IsNil)
	c.Assert(containers, check.HasLen, 1)
	c.Assert(containers[0].Status, check.Equals, provision.StatusStarting.String())
}

func (s *S) TestFollowLogsAndCommitForwardWaitFailure(c *check.C) {
	s.server.PrepareFailure("failed to wait for the container", "/containers/.*/wait")
	defer s.server.ResetFailure("failed to wait for the container")
	err := s.newFakeImage(s.p, "tsuru/python", nil)
	c.Assert(err, check.IsNil)
	app := provisiontest.NewFakeApp("myapp", "python", 1)
	cont := container.Container{AppName: "mightyapp"}
	err = cont.Create(&container.CreateArgs{
		App:         app,
		ImageID:     "tsuru/python",
		Commands:    []string{"foo"},
		Provisioner: s.p,
	})
	c.Assert(err, check.IsNil)
	err = cont.Start(&container.StartArgs{
		Provisioner: s.p,
		App:         app,
	})
	c.Assert(err, check.IsNil)
	err = cont.Stop(s.p)
	c.Assert(err, check.IsNil)
	buf := safe.NewBuffer(nil)
	args := runContainerActionsArgs{writer: buf, provisioner: s.p}
	context := action.FWContext{Params: []interface{}{args}, Previous: cont}
	imageId, err := followLogsAndCommit.Forward(context)
	c.Assert(err, check.ErrorMatches, `.*failed to wait for the container\n$`)
	c.Assert(imageId, check.IsNil)
}

func (s *S) TestRebalanceContainers(c *check.C) {
	p, err := s.startMultipleServersCluster()
	c.Assert(err, check.IsNil)
	err = s.newFakeImage(p, "tsuru/app-myapp", nil)
	c.Assert(err, check.IsNil)
	appInstance := provisiontest.NewFakeApp("myapp", "python", 0)
	defer p.Destroy(appInstance)
	p.Provision(appInstance)
	imageId, err := appCurrentImageName(appInstance.GetName())
	c.Assert(err, check.IsNil)
	_, err = addContainersWithHost(&changeUnitsPipelineArgs{
		toHost:      "localhost",
		toAdd:       map[string]*containersToAdd{"web": {Quantity: 5}},
		app:         appInstance,
		imageId:     imageId,
		provisioner: p,
	})
	c.Assert(err, check.IsNil)
	appStruct := &app.App{
		Name: appInstance.GetName(),
	}
	err = s.storage.Apps().Insert(appStruct)
	c.Assert(err, check.IsNil)
	buf := safe.NewBuffer(nil)
	err = p.rebalanceContainers(buf, false)
	c.Assert(err, check.IsNil)
	c1, err := p.listContainersByHost("localhost")
	c.Assert(err, check.IsNil)
	c2, err := p.listContainersByHost("127.0.0.1")
	c.Assert(err, check.IsNil)
	c.Assert((len(c1) == 3 && len(c2) == 2) || (len(c1) == 2 && len(c2) == 3), check.Equals, true)
}

func (s *S) TestEnsureContainersStartedForceStopOnlyOnFailure(c *check.C) {
	config.Set("docker:bs:image", "myregistry/tsuru/bs")
	_, err := nodecontainer.InitializeBS()
	c.Assert(err, check.IsNil)
	var reqs []*http.Request
	server, err := testing.NewServer("127.0.0.1:0", nil, func(r *http.Request) {
		reqs = append(reqs, r)
	})
	c.Assert(err, check.IsNil)
	defer server.Stop()
	errCount := 0
	server.CustomHandler("/containers/big-sibling", http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		reqs = append(reqs, r)
		if r.Method != "DELETE" {
			server.DefaultHandler().ServeHTTP(w, r)
			return
		}
		errCount++
		if errCount > 2 {
			server.DefaultHandler().ServeHTTP(w, r)
		} else {
			w.WriteHeader(http.StatusInternalServerError)
		}
	}))
	p, err := dockertest.NewFakeDockerProvisioner(server.URL())
	c.Assert(err, check.IsNil)
	defer p.Destroy()
	client, err := docker.NewClient(server.URL())
	c.Assert(err, check.IsNil)
	buf := safe.NewBuffer(nil)
	err = ensureContainersStarted(p, buf, true, nil)
	c.Assert(err, check.IsNil)
	reqs = nil
	err = ensureContainersStarted(p, buf, true, nil)
	c.Assert(err, check.IsNil)
	var paths []string
	for _, r := range reqs {
		paths = append(paths, r.Method+" "+r.URL.Path)
	}
	c.Assert(paths, check.DeepEquals, []string{
		"POST /images/create",
		"POST /containers/create",
		"POST /containers/big-sibling/stop",
		"DELETE /containers/big-sibling",
		"DELETE /containers/big-sibling",
		"DELETE /containers/big-sibling",
		"POST /containers/create",
		"GET /version",
		"POST /containers/big-sibling/start",
	})
	c.Assert(reqs[3].URL.Query().Get("force"), check.Equals, "")
	c.Assert(reqs[4].URL.Query().Get("force"), check.Equals, "1")
	c.Assert(reqs[5].URL.Query().Get("force"), check.Equals, "1")
	containers, err := client.ListContainers(docker.ListContainersOptions{All: true})
	c.Assert(err, check.IsNil)
	c.Assert(containers, check.HasLen, 1)
	container, err := client.InspectContainer(containers[0].ID)
	c.Assert(err, check.IsNil)
	c.Assert(container.Name, check.Equals, nodecontainer.BsDefaultName)
}

func (s *S) TestRebalanceContainersManyApps(c *check.C) {
	p, err := s.startMultipleServersCluster()
	c.Assert(err, check.IsNil)
	err = s.newFakeImage(p, "tsuru/app-myapp", nil)
	c.Assert(err, check.IsNil)
	err = s.newFakeImage(p, "tsuru/app-otherapp", nil)
	c.Assert(err, check.IsNil)
	appInstance := provisiontest.NewFakeApp("myapp", "python", 0)
	defer p.Destroy(appInstance)
	p.Provision(appInstance)
	appInstance2 := provisiontest.NewFakeApp("otherapp", "python", 0)
	defer p.Destroy(appInstance2)
	p.Provision(appInstance2)
	imageId, err := image.AppCurrentImageName(appInstance.GetName())
	c.Assert(err, check.IsNil)
	_, err = addContainersWithHost(&changeUnitsPipelineArgs{
		toHost:      "localhost",
		toAdd:       map[string]*containersToAdd{"web": {Quantity: 1}},
		app:         appInstance,
		imageId:     imageId,
		provisioner: p,
	})
	c.Assert(err, check.IsNil)
	imageId2, err := image.AppCurrentImageName(appInstance2.GetName())
	c.Assert(err, check.IsNil)
	_, err = addContainersWithHost(&changeUnitsPipelineArgs{
		toHost:      "localhost",
		toAdd:       map[string]*containersToAdd{"web": {Quantity: 1}},
		app:         appInstance2,
		imageId:     imageId2,
		provisioner: p,
	})
	c.Assert(err, check.IsNil)
	appStruct := &app.App{
		Name: appInstance.GetName(),
		Pool: "test-default",
	}
	err = s.storage.Apps().Insert(appStruct)
	c.Assert(err, check.IsNil)
	appStruct2 := &app.App{
		Name: appInstance2.GetName(),
		Pool: "test-default",
	}
	err = s.storage.Apps().Insert(appStruct2)
	c.Assert(err, check.IsNil)
	buf := safe.NewBuffer(nil)
	c1, err := p.listContainersByHost("localhost")
	c.Assert(err, check.IsNil)
	c.Assert(c1, check.HasLen, 2)
	err = p.rebalanceContainers(buf, false)
	c.Assert(err, check.IsNil)
	c1, err = p.listContainersByHost("localhost")
	c.Assert(err, check.IsNil)
	c.Assert(c1, check.HasLen, 1)
	c2, err := p.listContainersByHost("127.0.0.1")
	c.Assert(err, check.IsNil)
	c.Assert(c2, check.HasLen, 1)
}

func (s *S) TestBindAndHealthcheckDontHealtcheckForErroredApps(c *check.C) {
	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.WriteHeader(http.StatusNotFound)
	}))
	defer server.Close()
	conn, err := db.Conn()
	c.Assert(err, check.IsNil)
	defer conn.Close()
	dbApp := &app.App{Name: "myapp"}
	err = conn.Apps().Insert(dbApp)
	c.Assert(err, check.IsNil)
	defer conn.Apps().Remove(bson.M{"name": dbApp.Name})
	imageName := "tsuru/app-" + dbApp.Name
	customData := map[string]interface{}{
		"healthcheck": map[string]interface{}{
			"path":   "/x/y",
			"status": http.StatusOK,
		},
		"procfile": "web: python myapp.py",
	}
	err = s.newFakeImage(s.p, imageName, customData)
	c.Assert(err, check.IsNil)
	fakeApp := provisiontest.NewFakeApp(dbApp.Name, "python", 0)
	s.p.Provision(fakeApp)
	defer s.p.Destroy(fakeApp)
	buf := safe.NewBuffer(nil)
	contOpts := newContainerOpts{
		Status: "error",
	}
	oldContainer, err := s.newContainer(&contOpts, nil)
	c.Assert(err, check.IsNil)
	args := changeUnitsPipelineArgs{
		app:         fakeApp,
		provisioner: s.p,
		writer:      buf,
		toAdd:       map[string]*containersToAdd{"web": {Quantity: 2}},
		imageId:     "tsuru/app-" + dbApp.Name,
		toRemove:    []container{*oldContainer},
	}
	containers, err := addContainersWithHost(&args)
	c.Assert(err, check.IsNil)
	c.Assert(containers, check.HasLen, 2)
	url, _ := url.Parse(server.URL)
	host, port, _ := net.SplitHostPort(url.Host)
	containers[0].HostAddr = host
	containers[0].HostPort = port
	containers[1].HostAddr = host
	containers[1].HostPort = port
	context := action.FWContext{Params: []interface{}{args}, Previous: containers}
	result, err := bindAndHealthcheck.Forward(context)
	c.Assert(err, check.IsNil)
	resultContainers := result.([]container)
	c.Assert(resultContainers, check.DeepEquals, containers)
	u1 := containers[0].asUnit(fakeApp)
	u2 := containers[1].asUnit(fakeApp)
	c.Assert(fakeApp.HasBind(&u1), check.Equals, true)
	c.Assert(fakeApp.HasBind(&u2), check.Equals, true)
}

func (s *S) TestRebalanceContainersByHost(c *check.C) {
	otherServer, err := dtesting.NewServer("localhost:0", nil, nil)
	c.Assert(err, check.IsNil)
	defer otherServer.Stop()
	otherUrl := strings.Replace(otherServer.URL(), "127.0.0.1", "localhost", 1)
	p := &dockerProvisioner{}
	err = p.Initialize()
	c.Assert(err, check.IsNil)
	p.storage = &cluster.MapStorage{}
	p.scheduler = &segregatedScheduler{provisioner: p}
	p.cluster, err = cluster.New(p.scheduler, p.storage,
		cluster.Node{Address: s.server.URL(), Metadata: map[string]string{"pool": "pool1"}},
		cluster.Node{Address: otherUrl, Metadata: map[string]string{"pool": "pool1"}},
	)
	c.Assert(err, check.IsNil)
	opts := provision.AddPoolOptions{Name: "pool1"}
	err = provision.AddPool(opts)
	c.Assert(err, check.IsNil)
	err = provision.AddTeamsToPool("pool1", []string{"team1"})
	c.Assert(err, check.IsNil)
	err = s.newFakeImage(p, "tsuru/app-myapp", nil)
	c.Assert(err, check.IsNil)
	appInstance := provisiontest.NewFakeApp("myapp", "python", 0)
	defer p.Destroy(appInstance)
	p.Provision(appInstance)
	imageId, err := appCurrentImageName(appInstance.GetName())
	c.Assert(err, check.IsNil)
	_, err = addContainersWithHost(&changeUnitsPipelineArgs{
		toHost:      "localhost",
		toAdd:       map[string]*containersToAdd{"web": {Quantity: 5}},
		app:         appInstance,
		imageId:     imageId,
		provisioner: p,
	})
	c.Assert(err, check.IsNil)
	appStruct := &app.App{
		Name:      appInstance.GetName(),
		TeamOwner: "team1",
		Pool:      "pool1",
	}
	err = s.storage.Apps().Insert(appStruct)
	c.Assert(err, check.IsNil)
	c1, err := p.listContainersByHost("localhost")
	c.Assert(err, check.IsNil)
	c.Assert(c1, check.HasLen, 5)
	c2, err := p.listContainersByHost("127.0.0.1")
	c.Assert(err, check.IsNil)
	c.Assert(c2, check.HasLen, 0)
	err = p.Cluster().Unregister(otherUrl)
	c.Assert(err, check.IsNil)
	buf := safe.NewBuffer(nil)
	err = p.rebalanceContainersByHost(net.URLToHost(otherUrl), buf)
	c.Assert(err, check.IsNil)
	c.Assert(p.scheduler.ignoredContainers, check.IsNil)
	c2, err = p.listContainersByHost("127.0.0.1")
	c.Assert(err, check.IsNil)
	c.Assert(c2, check.HasLen, 5)
}

func (a *autoScaleConfig) rebalanceIfNeeded(event *autoScaleEvent, groupMetadata string, nodes []*cluster.Node) error {
	if a.preventRebalance {
		return nil
	}
	var rebalanceFilter map[string]string
	if a.groupByMetadata != "" {
		rebalanceFilter = map[string]string{a.groupByMetadata: groupMetadata}
	}
	if event.Action == "" {
		// No action yet, check if we need rebalance
		_, gap, err := a.provisioner.containerGapInNodes(nodes)
		buf := safe.NewBuffer(nil)
		dryProvisioner, err := a.provisioner.rebalanceContainersByFilter(buf, nil, rebalanceFilter, true)
		if err != nil {
			return fmt.Errorf("unable to run dry rebalance to check if rebalance is needed: %s - log: %s", err, buf.String())
		}
		if dryProvisioner == nil {
			return nil
		}
		_, gapAfter, err := dryProvisioner.containerGapInNodes(nodes)
		if err != nil {
			return fmt.Errorf("couldn't find containers from rebalanced nodes: %s", err)
		}
		if math.Abs((float64)(gap-gapAfter)) > 2.0 {
			err = event.update(scaleActionRebalance, fmt.Sprintf("gap is %d, after rebalance gap will be %d", gap, gapAfter))
			if err != nil {
				return fmt.Errorf("unable to update event: %s", err)
			}
		}
	}
	if event.Action != "" && event.Action != scaleActionRemove {
		a.logDebug("running rebalance, due to %q for %q: %s", event.Action, event.MetadataValue, event.Reason)
		buf := safe.NewBuffer(nil)
		var writer io.Writer = buf
		if a.writer != nil {
			writer = io.MultiWriter(buf, a.writer)
		}
		_, err := a.provisioner.rebalanceContainersByFilter(writer, nil, rebalanceFilter, false)
		if err != nil {
			return fmt.Errorf("unable to rebalance containers: %s - log: %s", err.Error(), buf.String())
		}
		return nil
	}
	return nil
}