Handle container links
Ensures that linked containers are restarted if any of their dependencies are restarted -- and makes sure that everything happens in the correct order.pull/1/head
Brian DeHamer
10 years ago
parent
ce4ed7316c
commit
c02c4b9ec1
@ -0,0 +1,116 @@
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package docker
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import (
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"log"
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"github.com/samalba/dockerclient"
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)
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var (
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pullImages bool
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)
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func init() {
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pullImages = true
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}
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type Client interface {
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ListContainers() ([]Container, error)
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RefreshImage(container *Container) error
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Stop(container Container) error
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Start(container Container) error
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}
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func NewClient() Client {
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docker, err := dockerclient.NewDockerClient("unix:///var/run/docker.sock", nil)
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if err != nil {
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log.Fatalf("Error instantiating Docker client: %s\n", err)
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}
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return DockerClient{api: docker}
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}
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type DockerClient struct {
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api dockerclient.Client
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}
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func (client DockerClient) ListContainers() ([]Container, error) {
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cs := []Container{}
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runningContainers, err := client.api.ListContainers(false, false, "")
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if err != nil {
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return nil, err
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}
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for _, runningContainer := range runningContainers {
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containerInfo, err := client.api.InspectContainer(runningContainer.Id)
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if err != nil {
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return nil, err
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}
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imageInfo, err := client.api.InspectImage(containerInfo.Image)
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if err != nil {
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return nil, err
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}
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cs = append(cs, Container{containerInfo: containerInfo, imageInfo: imageInfo})
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}
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return cs, nil
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}
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func (client DockerClient) RefreshImage(c *Container) error {
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containerInfo := c.containerInfo
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oldImageInfo := c.imageInfo
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imageName := containerInfo.Config.Image
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if pullImages {
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log.Printf("Pulling %s for %s\n", imageName, c.Name())
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if err := client.api.PullImage(imageName, nil); err != nil {
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return err
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}
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}
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newImageInfo, err := client.api.InspectImage(imageName)
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if err != nil {
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return err
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}
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if newImageInfo.Id != oldImageInfo.Id {
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log.Printf("Found new %s image (%s)\n", imageName, newImageInfo.Id)
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c.Stale = true
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}
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return nil
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}
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func (client DockerClient) Stop(c Container) error {
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signal := "SIGTERM"
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if sig, ok := c.containerInfo.Config.Labels["com.centurylinklabs.watchtower.stop-signal"]; ok {
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signal = sig
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}
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log.Printf("Stopping: %s\n", c.Name())
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if err := client.api.KillContainer(c.containerInfo.Id, signal); err != nil {
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return err
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}
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return client.api.RemoveContainer(c.containerInfo.Id, true, false)
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}
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func (client DockerClient) Start(c Container) error {
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config := c.runtimeConfig()
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hostConfig := c.hostConfig()
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log.Printf("Starting: %s\n", c.Name())
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newContainerId, err := client.api.CreateContainer(config, c.Name())
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if err != nil {
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return err
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}
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return client.api.StartContainer(newContainerId, hostConfig)
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}
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@ -0,0 +1,308 @@
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package docker
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import (
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"errors"
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"testing"
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"github.com/samalba/dockerclient"
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"github.com/samalba/dockerclient/mockclient"
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"github.com/stretchr/testify/assert"
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"github.com/stretchr/testify/mock"
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)
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func TestListContainers_Success(t *testing.T) {
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ci := &dockerclient.ContainerInfo{Image: "abc123"}
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ii := &dockerclient.ImageInfo{}
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api := mockclient.NewMockClient()
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api.On("ListContainers", false, false, "").Return([]dockerclient.Container{{Id: "foo"}}, nil)
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api.On("InspectContainer", "foo").Return(ci, nil)
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api.On("InspectImage", "abc123").Return(ii, nil)
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client := DockerClient{api: api}
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cs, err := client.ListContainers()
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assert.NoError(t, err)
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assert.Len(t, cs, 1)
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assert.Equal(t, ci, cs[0].containerInfo)
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assert.Equal(t, ii, cs[0].imageInfo)
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api.AssertExpectations(t)
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}
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func TestListContainers_ListError(t *testing.T) {
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api := mockclient.NewMockClient()
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api.On("ListContainers", false, false, "").Return([]dockerclient.Container{}, errors.New("oops"))
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client := DockerClient{api: api}
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_, err := client.ListContainers()
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assert.Error(t, err)
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assert.EqualError(t, err, "oops")
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api.AssertExpectations(t)
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}
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func TestListContainers_InspectContainerError(t *testing.T) {
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api := mockclient.NewMockClient()
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api.On("ListContainers", false, false, "").Return([]dockerclient.Container{{Id: "foo"}}, nil)
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api.On("InspectContainer", "foo").Return(&dockerclient.ContainerInfo{}, errors.New("uh-oh"))
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client := DockerClient{api: api}
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_, err := client.ListContainers()
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assert.Error(t, err)
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assert.EqualError(t, err, "uh-oh")
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api.AssertExpectations(t)
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}
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func TestListContainers_InspectImageError(t *testing.T) {
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ci := &dockerclient.ContainerInfo{Image: "abc123"}
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ii := &dockerclient.ImageInfo{}
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api := mockclient.NewMockClient()
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api.On("ListContainers", false, false, "").Return([]dockerclient.Container{{Id: "foo"}}, nil)
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api.On("InspectContainer", "foo").Return(ci, nil)
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api.On("InspectImage", "abc123").Return(ii, errors.New("whoops"))
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client := DockerClient{api: api}
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_, err := client.ListContainers()
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assert.Error(t, err)
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assert.EqualError(t, err, "whoops")
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api.AssertExpectations(t)
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}
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func TestRefreshImage_NotStaleSuccess(t *testing.T) {
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c := &Container{
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containerInfo: &dockerclient.ContainerInfo{
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Name: "foo",
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Config: &dockerclient.ContainerConfig{Image: "bar"},
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},
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imageInfo: &dockerclient.ImageInfo{Id: "abc123"},
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}
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newImageInfo := &dockerclient.ImageInfo{Id: "abc123"}
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api := mockclient.NewMockClient()
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api.On("PullImage", "bar", mock.Anything).Return(nil)
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api.On("InspectImage", "bar").Return(newImageInfo, nil)
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client := DockerClient{api: api}
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err := client.RefreshImage(c)
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assert.NoError(t, err)
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assert.False(t, c.Stale)
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api.AssertExpectations(t)
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}
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func TestRefreshImage_StaleSuccess(t *testing.T) {
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c := &Container{
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containerInfo: &dockerclient.ContainerInfo{
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Name: "foo",
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Config: &dockerclient.ContainerConfig{Image: "bar"},
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},
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imageInfo: &dockerclient.ImageInfo{Id: "abc123"},
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}
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newImageInfo := &dockerclient.ImageInfo{Id: "xyz789"}
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api := mockclient.NewMockClient()
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api.On("PullImage", "bar", mock.Anything).Return(nil)
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api.On("InspectImage", "bar").Return(newImageInfo, nil)
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client := DockerClient{api: api}
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err := client.RefreshImage(c)
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assert.NoError(t, err)
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assert.True(t, c.Stale)
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api.AssertExpectations(t)
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}
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func TestRefreshImage_PullImageError(t *testing.T) {
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c := &Container{
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containerInfo: &dockerclient.ContainerInfo{
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Name: "foo",
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Config: &dockerclient.ContainerConfig{Image: "bar"},
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},
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imageInfo: &dockerclient.ImageInfo{Id: "abc123"},
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}
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api := mockclient.NewMockClient()
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api.On("PullImage", "bar", mock.Anything).Return(errors.New("oops"))
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client := DockerClient{api: api}
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err := client.RefreshImage(c)
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assert.Error(t, err)
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assert.EqualError(t, err, "oops")
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api.AssertExpectations(t)
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}
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func TestRefreshImage_InspectImageError(t *testing.T) {
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c := &Container{
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containerInfo: &dockerclient.ContainerInfo{
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Name: "foo",
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Config: &dockerclient.ContainerConfig{Image: "bar"},
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},
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imageInfo: &dockerclient.ImageInfo{Id: "abc123"},
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}
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newImageInfo := &dockerclient.ImageInfo{}
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api := mockclient.NewMockClient()
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api.On("PullImage", "bar", mock.Anything).Return(nil)
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api.On("InspectImage", "bar").Return(newImageInfo, errors.New("uh-oh"))
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client := DockerClient{api: api}
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err := client.RefreshImage(c)
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assert.Error(t, err)
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assert.EqualError(t, err, "uh-oh")
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api.AssertExpectations(t)
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}
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func TestStop_DefaultSuccess(t *testing.T) {
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c := Container{
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containerInfo: &dockerclient.ContainerInfo{
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Name: "foo",
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Id: "abc123",
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Config: &dockerclient.ContainerConfig{},
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},
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}
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api := mockclient.NewMockClient()
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api.On("KillContainer", "abc123", "SIGTERM").Return(nil)
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api.On("RemoveContainer", "abc123", true, false).Return(nil)
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client := DockerClient{api: api}
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err := client.Stop(c)
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assert.NoError(t, err)
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api.AssertExpectations(t)
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}
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func TestStop_CustomSignalSuccess(t *testing.T) {
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c := Container{
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containerInfo: &dockerclient.ContainerInfo{
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Name: "foo",
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Id: "abc123",
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Config: &dockerclient.ContainerConfig{
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Labels: map[string]string{"com.centurylinklabs.watchtower.stop-signal": "SIGUSR1"}},
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},
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}
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api := mockclient.NewMockClient()
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api.On("KillContainer", "abc123", "SIGUSR1").Return(nil)
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api.On("RemoveContainer", "abc123", true, false).Return(nil)
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client := DockerClient{api: api}
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err := client.Stop(c)
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assert.NoError(t, err)
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api.AssertExpectations(t)
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}
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func TestStop_KillContainerError(t *testing.T) {
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c := Container{
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containerInfo: &dockerclient.ContainerInfo{
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Name: "foo",
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Id: "abc123",
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Config: &dockerclient.ContainerConfig{},
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},
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}
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api := mockclient.NewMockClient()
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api.On("KillContainer", "abc123", "SIGTERM").Return(errors.New("oops"))
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client := DockerClient{api: api}
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err := client.Stop(c)
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assert.Error(t, err)
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assert.EqualError(t, err, "oops")
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api.AssertExpectations(t)
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}
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func TestStop_RemoveContainerError(t *testing.T) {
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c := Container{
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containerInfo: &dockerclient.ContainerInfo{
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Name: "foo",
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Id: "abc123",
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Config: &dockerclient.ContainerConfig{},
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},
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}
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api := mockclient.NewMockClient()
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api.On("KillContainer", "abc123", "SIGTERM").Return(nil)
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api.On("RemoveContainer", "abc123", true, false).Return(errors.New("whoops"))
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client := DockerClient{api: api}
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err := client.Stop(c)
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assert.Error(t, err)
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assert.EqualError(t, err, "whoops")
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api.AssertExpectations(t)
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}
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func TestStart_Success(t *testing.T) {
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c := Container{
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containerInfo: &dockerclient.ContainerInfo{
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Name: "foo",
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Config: &dockerclient.ContainerConfig{},
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HostConfig: &dockerclient.HostConfig{},
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},
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imageInfo: &dockerclient.ImageInfo{
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Config: &dockerclient.ContainerConfig{},
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},
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}
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api := mockclient.NewMockClient()
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api.On("CreateContainer", mock.AnythingOfType("*dockerclient.ContainerConfig"), "foo").Return("def789", nil)
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api.On("StartContainer", "def789", mock.AnythingOfType("*dockerclient.HostConfig")).Return(nil)
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client := DockerClient{api: api}
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err := client.Start(c)
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assert.NoError(t, err)
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api.AssertExpectations(t)
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}
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func TestStart_CreateContainerError(t *testing.T) {
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c := Container{
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containerInfo: &dockerclient.ContainerInfo{
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Name: "foo",
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Config: &dockerclient.ContainerConfig{},
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HostConfig: &dockerclient.HostConfig{},
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},
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imageInfo: &dockerclient.ImageInfo{
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Config: &dockerclient.ContainerConfig{},
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},
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}
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api := mockclient.NewMockClient()
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api.On("CreateContainer", mock.Anything, "foo").Return("", errors.New("oops"))
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client := DockerClient{api: api}
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err := client.Start(c)
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assert.Error(t, err)
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assert.EqualError(t, err, "oops")
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api.AssertExpectations(t)
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}
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func TestStart_StartContainerError(t *testing.T) {
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c := Container{
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containerInfo: &dockerclient.ContainerInfo{
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Name: "foo",
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Config: &dockerclient.ContainerConfig{},
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HostConfig: &dockerclient.HostConfig{},
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},
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imageInfo: &dockerclient.ImageInfo{
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Config: &dockerclient.ContainerConfig{},
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},
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}
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api := mockclient.NewMockClient()
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api.On("CreateContainer", mock.Anything, "foo").Return("def789", nil)
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api.On("StartContainer", "def789", mock.Anything).Return(errors.New("whoops"))
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client := DockerClient{api: api}
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err := client.Start(c)
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assert.Error(t, err)
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assert.EqualError(t, err, "whoops")
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api.AssertExpectations(t)
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}
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@ -0,0 +1,103 @@
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package docker
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import (
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"fmt"
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"strings"
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"github.com/samalba/dockerclient"
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)
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type Container struct {
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Stale bool
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containerInfo *dockerclient.ContainerInfo
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imageInfo *dockerclient.ImageInfo
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}
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func (c Container) Name() string {
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return c.containerInfo.Name
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}
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func (c Container) Links() []string {
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links := []string{}
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if (c.containerInfo != nil) && (c.containerInfo.HostConfig != nil) {
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for _, link := range c.containerInfo.HostConfig.Links {
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name := strings.Split(link, ":")[0]
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links = append(links, name)
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}
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}
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return links
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}
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// Ideally, we'd just be able to take the ContainerConfig from the old container
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// and use it as the starting point for creating the new container; however,
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// the ContainerConfig that comes back from the Inspect call merges the default
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// configuration (the stuff specified in the metadata for the image itself)
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// with the overridden configuration (the stuff that you might specify as part
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// of the "docker run"). In order to avoid unintentionally overriding the
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// defaults in the new image we need to separate the override options from the
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// default options. To do this we have to compare the ContainerConfig for the
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// running container with the ContainerConfig from the image that container was
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// started from. This function returns a ContainerConfig which contains just
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// the options overridden at runtime.
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func (c Container) runtimeConfig() *dockerclient.ContainerConfig {
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config := c.containerInfo.Config
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imageConfig := c.imageInfo.Config
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if config.WorkingDir == imageConfig.WorkingDir {
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config.WorkingDir = ""
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}
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if config.User == imageConfig.User {
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config.User = ""
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}
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if sliceEqual(config.Cmd, imageConfig.Cmd) {
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config.Cmd = []string{}
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}
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if sliceEqual(config.Entrypoint, imageConfig.Entrypoint) {
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config.Entrypoint = []string{}
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}
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config.Env = sliceSubtract(config.Env, imageConfig.Env)
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config.Labels = stringMapSubtract(config.Labels, imageConfig.Labels)
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config.Volumes = structMapSubtract(config.Volumes, imageConfig.Volumes)
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config.ExposedPorts = structMapSubtract(config.ExposedPorts, imageConfig.ExposedPorts)
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for p, _ := range c.containerInfo.HostConfig.PortBindings {
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config.ExposedPorts[p] = struct{}{}
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}
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return config
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}
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// Any links in the HostConfig need to be re-written before they can be
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// re-submitted to the Docker create API.
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func (c Container) hostConfig() *dockerclient.HostConfig {
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hostConfig := c.containerInfo.HostConfig
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for i, link := range hostConfig.Links {
|
||||
name := link[0:strings.Index(link, ":")]
|
||||
alias := link[strings.LastIndex(link, "/"):]
|
||||
|
||||
hostConfig.Links[i] = fmt.Sprintf("%s:%s", name, alias)
|
||||
}
|
||||
|
||||
return hostConfig
|
||||
}
|
||||
|
||||
func NewTestContainer(name string, links []string) Container {
|
||||
return Container{
|
||||
containerInfo: &dockerclient.ContainerInfo{
|
||||
Name: name,
|
||||
HostConfig: &dockerclient.HostConfig{
|
||||
Links: links,
|
||||
},
|
||||
},
|
||||
}
|
||||
}
|
||||
@ -0,0 +1,32 @@
|
||||
package docker
|
||||
|
||||
import (
|
||||
"testing"
|
||||
|
||||
"github.com/samalba/dockerclient"
|
||||
"github.com/stretchr/testify/assert"
|
||||
)
|
||||
|
||||
func TestName(t *testing.T) {
|
||||
c := Container{
|
||||
containerInfo: &dockerclient.ContainerInfo{Name: "foo"},
|
||||
}
|
||||
|
||||
name := c.Name()
|
||||
|
||||
assert.Equal(t, "foo", name)
|
||||
}
|
||||
|
||||
func TestLinks(t *testing.T) {
|
||||
c := Container{
|
||||
containerInfo: &dockerclient.ContainerInfo{
|
||||
HostConfig: &dockerclient.HostConfig{
|
||||
Links: []string{"foo:foo", "bar:bar"},
|
||||
},
|
||||
},
|
||||
}
|
||||
|
||||
links := c.Links()
|
||||
|
||||
assert.Equal(t, []string{"foo", "bar"}, links)
|
||||
}
|
||||
@ -0,0 +1,64 @@
|
||||
package docker
|
||||
|
||||
func sliceEqual(s1, s2 []string) bool {
|
||||
if len(s1) != len(s2) {
|
||||
return false
|
||||
}
|
||||
|
||||
for i := range s1 {
|
||||
if s1[i] != s2[i] {
|
||||
return false
|
||||
}
|
||||
}
|
||||
|
||||
return true
|
||||
}
|
||||
|
||||
func sliceSubtract(a1, a2 []string) []string {
|
||||
a := []string{}
|
||||
|
||||
for _, e1 := range a1 {
|
||||
found := false
|
||||
|
||||
for _, e2 := range a2 {
|
||||
if e1 == e2 {
|
||||
found = true
|
||||
break
|
||||
}
|
||||
}
|
||||
|
||||
if !found {
|
||||
a = append(a, e1)
|
||||
}
|
||||
}
|
||||
|
||||
return a
|
||||
}
|
||||
|
||||
func stringMapSubtract(m1, m2 map[string]string) map[string]string {
|
||||
m := map[string]string{}
|
||||
|
||||
for k1, v1 := range m1 {
|
||||
if v2, ok := m2[k1]; ok {
|
||||
if v2 != v1 {
|
||||
m[k1] = v1
|
||||
}
|
||||
} else {
|
||||
m[k1] = v1
|
||||
}
|
||||
}
|
||||
|
||||
return m
|
||||
}
|
||||
|
||||
func structMapSubtract(m1, m2 map[string]struct{}) map[string]struct{} {
|
||||
m := map[string]struct{}{}
|
||||
|
||||
for k1, v1 := range m1 {
|
||||
if _, ok := m2[k1]; !ok {
|
||||
m[k1] = v1
|
||||
}
|
||||
}
|
||||
|
||||
return m
|
||||
}
|
||||
@ -1,112 +0,0 @@
|
||||
package updater
|
||||
|
||||
import (
|
||||
"github.com/samalba/dockerclient"
|
||||
)
|
||||
|
||||
// Ideally, we'd just be able to take the ContainerConfig from the old container
|
||||
// and use it as the starting point for creating the new container; however,
|
||||
// the ContainerConfig that comes back from the Inspect call merges the default
|
||||
// configuration (the stuff specified in the metadata for the image itself)
|
||||
// with the overridden configuration (the stuff that you might specify as part
|
||||
// of the "docker run"). In order to avoid unintentionally overriding the
|
||||
// defaults in the new image we need to separate the override options from the
|
||||
// default options. To do this we have to compare the ContainerConfig for the
|
||||
// running container with the ContainerConfig from the image that container was
|
||||
// started from. This function returns a ContainerConfig which contains just
|
||||
// the override options.
|
||||
func GenerateContainerConfig(oldContainerInfo *dockerclient.ContainerInfo, oldImageConfig *dockerclient.ContainerConfig) *dockerclient.ContainerConfig {
|
||||
config := oldContainerInfo.Config
|
||||
|
||||
if config.WorkingDir == oldImageConfig.WorkingDir {
|
||||
config.WorkingDir = ""
|
||||
}
|
||||
|
||||
if config.User == oldImageConfig.User {
|
||||
config.User = ""
|
||||
}
|
||||
|
||||
if sliceEqual(config.Cmd, oldImageConfig.Cmd) {
|
||||
config.Cmd = []string{}
|
||||
}
|
||||
|
||||
if sliceEqual(config.Entrypoint, oldImageConfig.Entrypoint) {
|
||||
config.Entrypoint = []string{}
|
||||
}
|
||||
|
||||
config.Env = arraySubtract(config.Env, oldImageConfig.Env)
|
||||
|
||||
config.Labels = stringMapSubtract(config.Labels, oldImageConfig.Labels)
|
||||
|
||||
config.Volumes = structMapSubtract(config.Volumes, oldImageConfig.Volumes)
|
||||
|
||||
config.ExposedPorts = structMapSubtract(config.ExposedPorts, oldImageConfig.ExposedPorts)
|
||||
for p, _ := range oldContainerInfo.HostConfig.PortBindings {
|
||||
config.ExposedPorts[p] = struct{}{}
|
||||
}
|
||||
|
||||
return config
|
||||
}
|
||||
|
||||
func sliceEqual(s1, s2 []string) bool {
|
||||
if len(s1) != len(s2) {
|
||||
return false
|
||||
}
|
||||
|
||||
for i := range s1 {
|
||||
if s1[i] != s2[i] {
|
||||
return false
|
||||
}
|
||||
}
|
||||
|
||||
return true
|
||||
}
|
||||
|
||||
func stringMapSubtract(m1, m2 map[string]string) map[string]string {
|
||||
m := map[string]string{}
|
||||
|
||||
for k1, v1 := range m1 {
|
||||
if v2, ok := m2[k1]; ok {
|
||||
if v2 != v1 {
|
||||
m[k1] = v1
|
||||
}
|
||||
} else {
|
||||
m[k1] = v1
|
||||
}
|
||||
}
|
||||
|
||||
return m
|
||||
}
|
||||
|
||||
func structMapSubtract(m1, m2 map[string]struct{}) map[string]struct{} {
|
||||
m := map[string]struct{}{}
|
||||
|
||||
for k1, v1 := range m1 {
|
||||
if _, ok := m2[k1]; !ok {
|
||||
m[k1] = v1
|
||||
}
|
||||
}
|
||||
|
||||
return m
|
||||
}
|
||||
|
||||
func arraySubtract(a1, a2 []string) []string {
|
||||
a := []string{}
|
||||
|
||||
for _, e1 := range a1 {
|
||||
found := false
|
||||
|
||||
for _, e2 := range a2 {
|
||||
if e1 == e2 {
|
||||
found = true
|
||||
break
|
||||
}
|
||||
}
|
||||
|
||||
if !found {
|
||||
a = append(a, e1)
|
||||
}
|
||||
}
|
||||
|
||||
return a
|
||||
}
|
||||
@ -0,0 +1,74 @@
|
||||
package updater
|
||||
|
||||
import (
|
||||
"fmt"
|
||||
|
||||
"github.com/CenturyLinkLabs/watchtower/docker"
|
||||
)
|
||||
|
||||
type ContainerSorter struct {
|
||||
unvisited []docker.Container
|
||||
marked map[string]bool
|
||||
sorted []docker.Container
|
||||
}
|
||||
|
||||
func (cs *ContainerSorter) Sort(containers []docker.Container) ([]docker.Container, error) {
|
||||
cs.unvisited = containers
|
||||
cs.marked = map[string]bool{}
|
||||
|
||||
for len(cs.unvisited) > 0 {
|
||||
if err := cs.visit(cs.unvisited[0]); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
}
|
||||
|
||||
return cs.sorted, nil
|
||||
}
|
||||
|
||||
func (cs *ContainerSorter) visit(c docker.Container) error {
|
||||
|
||||
if _, ok := cs.marked[c.Name()]; ok {
|
||||
return fmt.Errorf("Circular reference to %s", c.Name())
|
||||
}
|
||||
|
||||
// Mark any visited node so that circular references can be detected
|
||||
cs.marked[c.Name()] = true
|
||||
defer delete(cs.marked, c.Name())
|
||||
|
||||
// Recursively visit links
|
||||
for _, linkName := range c.Links() {
|
||||
if linkedContainer := cs.findUnvisited(linkName); linkedContainer != nil {
|
||||
if err := cs.visit(*linkedContainer); err != nil {
|
||||
return err
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// Move container from unvisited to sorted
|
||||
cs.removeUnvisited(c)
|
||||
cs.sorted = append(cs.sorted, c)
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
func (cs *ContainerSorter) findUnvisited(name string) *docker.Container {
|
||||
for _, c := range cs.unvisited {
|
||||
if c.Name() == name {
|
||||
return &c
|
||||
}
|
||||
}
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
func (cs *ContainerSorter) removeUnvisited(c docker.Container) {
|
||||
var idx int
|
||||
for i := range cs.unvisited {
|
||||
if cs.unvisited[i].Name() == c.Name() {
|
||||
idx = i
|
||||
break
|
||||
}
|
||||
}
|
||||
|
||||
cs.unvisited = append(cs.unvisited[0:idx], cs.unvisited[idx+1:]...)
|
||||
}
|
||||
@ -0,0 +1,37 @@
|
||||
package updater
|
||||
|
||||
import (
|
||||
"testing"
|
||||
|
||||
"github.com/CenturyLinkLabs/watchtower/docker"
|
||||
"github.com/stretchr/testify/assert"
|
||||
)
|
||||
|
||||
func TestContainerSorter_Success(t *testing.T) {
|
||||
c1 := docker.NewTestContainer("1", []string{})
|
||||
c2 := docker.NewTestContainer("2", []string{"1:"})
|
||||
c3 := docker.NewTestContainer("3", []string{"2:"})
|
||||
c4 := docker.NewTestContainer("4", []string{"3:"})
|
||||
c5 := docker.NewTestContainer("5", []string{"4:"})
|
||||
c6 := docker.NewTestContainer("6", []string{"5:", "3:"})
|
||||
containers := []docker.Container{c6, c2, c4, c1, c3, c5}
|
||||
|
||||
cs := ContainerSorter{}
|
||||
result, err := cs.Sort(containers)
|
||||
|
||||
assert.NoError(t, err)
|
||||
assert.Equal(t, []docker.Container{c1, c2, c3, c4, c5, c6}, result)
|
||||
}
|
||||
|
||||
func TestContainerSorter_Error(t *testing.T) {
|
||||
c1 := docker.NewTestContainer("1", []string{"3:"})
|
||||
c2 := docker.NewTestContainer("2", []string{"1:"})
|
||||
c3 := docker.NewTestContainer("3", []string{"2:"})
|
||||
containers := []docker.Container{c1, c2, c3}
|
||||
|
||||
cs := ContainerSorter{}
|
||||
_, err := cs.Sort(containers)
|
||||
|
||||
assert.Error(t, err)
|
||||
assert.EqualError(t, err, "Circular reference to 1")
|
||||
}
|
||||
@ -1,81 +1,71 @@
|
||||
package updater
|
||||
|
||||
import (
|
||||
"log"
|
||||
|
||||
"github.com/samalba/dockerclient"
|
||||
)
|
||||
|
||||
var (
|
||||
client dockerclient.Client
|
||||
"github.com/CenturyLinkLabs/watchtower/docker"
|
||||
)
|
||||
|
||||
func init() {
|
||||
docker, err := dockerclient.NewDockerClient("unix:///var/run/docker.sock", nil)
|
||||
func Run() error {
|
||||
client := docker.NewClient()
|
||||
containers, err := client.ListContainers()
|
||||
if err != nil {
|
||||
log.Fatalf("Error instantiating Docker client: %s\n", err)
|
||||
return err
|
||||
}
|
||||
|
||||
client = docker
|
||||
for i := range containers {
|
||||
if err := client.RefreshImage(&containers[i]); err != nil {
|
||||
return err
|
||||
}
|
||||
}
|
||||
|
||||
func Run() error {
|
||||
containers, _ := client.ListContainers(false, false, "")
|
||||
|
||||
for _, container := range containers {
|
||||
|
||||
oldContainerInfo, _ := client.InspectContainer(container.Id)
|
||||
name := oldContainerInfo.Name
|
||||
oldImageId := oldContainerInfo.Image
|
||||
log.Printf("Running: %s (%s)\n", container.Image, oldImageId)
|
||||
|
||||
oldImageInfo, _ := client.InspectImage(oldImageId)
|
||||
|
||||
// First check to see if a newer image has already been built
|
||||
newImageInfo, _ := client.InspectImage(container.Image)
|
||||
|
||||
if newImageInfo.Id == oldImageInfo.Id {
|
||||
_ = client.PullImage(container.Image, nil)
|
||||
newImageInfo, _ = client.InspectImage(container.Image)
|
||||
containers, err = sortContainers(containers)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
newImageId := newImageInfo.Id
|
||||
log.Printf("Latest: %s (%s)\n", container.Image, newImageId)
|
||||
checkDependencies(containers)
|
||||
|
||||
if newImageId != oldImageId {
|
||||
log.Printf("Restarting %s with new image\n", name)
|
||||
if err := stopContainer(oldContainerInfo); err != nil {
|
||||
// Stop stale containers in reverse order
|
||||
for i := len(containers) - 1; i >= 0; i-- {
|
||||
container := containers[i]
|
||||
if container.Stale {
|
||||
if err := client.Stop(container); err != nil {
|
||||
return err
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
config := GenerateContainerConfig(oldContainerInfo, oldImageInfo.Config)
|
||||
|
||||
hostConfig := oldContainerInfo.HostConfig
|
||||
_ = startContainer(name, config, hostConfig)
|
||||
// Restart stale containers in sorted order
|
||||
for _, container := range containers {
|
||||
if container.Stale {
|
||||
if err := client.Start(container); err != nil {
|
||||
return err
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
func stopContainer(container *dockerclient.ContainerInfo) error {
|
||||
signal := "SIGTERM"
|
||||
|
||||
if sig, ok := container.Config.Labels["com.centurylinklabs.watchtower.stop-signal"]; ok {
|
||||
signal = sig
|
||||
func sortContainers(containers []docker.Container) ([]docker.Container, error) {
|
||||
sorter := ContainerSorter{}
|
||||
return sorter.Sort(containers)
|
||||
}
|
||||
|
||||
if err := client.KillContainer(container.Id, signal); err != nil {
|
||||
return err
|
||||
}
|
||||
func checkDependencies(containers []docker.Container) {
|
||||
|
||||
return client.RemoveContainer(container.Id, true, false)
|
||||
for i, parent := range containers {
|
||||
if parent.Stale {
|
||||
continue
|
||||
}
|
||||
|
||||
func startContainer(name string, config *dockerclient.ContainerConfig, hostConfig *dockerclient.HostConfig) error {
|
||||
newContainerId, err := client.CreateContainer(config, name)
|
||||
if err != nil {
|
||||
return err
|
||||
LinkLoop:
|
||||
for _, linkName := range parent.Links() {
|
||||
for _, child := range containers {
|
||||
if child.Name() == linkName && child.Stale {
|
||||
containers[i].Stale = true
|
||||
break LinkLoop
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
return client.StartContainer(newContainerId, hostConfig)
|
||||
}
|
||||
|
||||
@ -0,0 +1,29 @@
|
||||
package updater
|
||||
|
||||
import (
|
||||
"testing"
|
||||
|
||||
"github.com/CenturyLinkLabs/watchtower/docker"
|
||||
"github.com/stretchr/testify/assert"
|
||||
)
|
||||
|
||||
func TestCheckDependencies(t *testing.T) {
|
||||
cs := []docker.Container{
|
||||
docker.NewTestContainer("1", []string{}),
|
||||
docker.NewTestContainer("2", []string{"1:"}),
|
||||
docker.NewTestContainer("3", []string{"2:"}),
|
||||
docker.NewTestContainer("4", []string{"3:"}),
|
||||
docker.NewTestContainer("5", []string{"4:"}),
|
||||
docker.NewTestContainer("6", []string{"5:"}),
|
||||
}
|
||||
cs[3].Stale = true
|
||||
|
||||
checkDependencies(cs)
|
||||
|
||||
assert.False(t, cs[0].Stale)
|
||||
assert.False(t, cs[1].Stale)
|
||||
assert.False(t, cs[2].Stale)
|
||||
assert.True(t, cs[3].Stale)
|
||||
assert.True(t, cs[4].Stale)
|
||||
assert.True(t, cs[5].Stale)
|
||||
}
|
||||
Loading…
Reference in New Issue