Make it possible to use watchtower to update exited or created containers as well (#289)

* feature/112: add additional tests that verify include-stopped

* feature/112: implement include-stopped

* feature/112: update readme and cli help

* feature/112: fix linting issues

* remove superfluous logging

README.md

@@ -157,6 +157,7 @@ docker run --rm containrrr/watchtower --help
 - `--tlsverify` Use TLS when connecting to the Docker socket and verify the server's certificate.
 - `--debug` Enable debug mode. When this option is specified you'll see more verbose logging in the watchtower log file.
 - `--monitor-only` Will only monitor for new images, not update the containers.
+- `--include-stopped` Will also include created and exited containers.
 - `--help` Show documentation about the supported flags.
 
 See below for options used to configure notifications.

app/app.go

@@ -157,6 +157,12 @@ func SetupCliFlags(app *cli.App) {
 		cli.BoolFlag{
 			Name:   "run-once",
 			Usage:  "Run once now and exit",
+			EnvVar: "WATCHTOWER_RUN_ONCE",
+		},
+		cli.BoolFlag{
+			Name:   "include-stopped",
+			Usage:  "Will also include created and exited containers",
+			EnvVar: "WATCHTOWER_INCLUDE_STOPPED",
 		},
 	}
 }

container/client.go

@@ -2,6 +2,8 @@ package container
 
 import (
 	"fmt"
+	"github.com/docker/docker/api/types/container"
+	"github.com/docker/docker/api/types/filters"
 	"io/ioutil"
 	"time"
 
@@ -33,36 +35,48 @@ type Client interface {
 //  * DOCKER_HOST			the docker-engine host to send api requests to
 //  * DOCKER_TLS_VERIFY		whether to verify tls certificates
 //  * DOCKER_API_VERSION	the minimum docker api version to work with
-func NewClient(pullImages bool) Client {
+func NewClient(pullImages bool, includeStopped bool) Client {
 	cli, err := dockerclient.NewClientWithOpts(dockerclient.FromEnv)
 
 	if err != nil {
 		log.Fatalf("Error instantiating Docker client: %s", err)
 	}
 
-	return dockerClient{api: cli, pullImages: pullImages}
+	return dockerClient{
+		api:            cli,
+		pullImages:     pullImages,
+		includeStopped: includeStopped,
+	}
 }
 
 type dockerClient struct {
 	api            dockerclient.CommonAPIClient
 	pullImages     bool
+	includeStopped bool
 }
 
 func (client dockerClient) ListContainers(fn Filter) ([]Container, error) {
 	cs := []Container{}
 	bg := context.Background()
 
+	if client.includeStopped {
+		log.Debug("Retrieving containers including stopped and exited")
+	} else {
 		log.Debug("Retrieving running containers")
+	}
 
-	runningContainers, err := client.api.ContainerList(
+	filter := client.createListFilter()
+	containers, err := client.api.ContainerList(
 		bg,
-		types.ContainerListOptions{})
+		types.ContainerListOptions{
+			Filters: filter,
+		})
 	
 	if err != nil {
 		return nil, err
 	}
 
-	for _, runningContainer := range runningContainers {
+	for _, runningContainer := range containers {
 		containerInfo, err := client.api.ContainerInspect(bg, runningContainer.ID)
 		if err != nil {
 			return nil, err
@@ -83,6 +97,18 @@ func (client dockerClient) ListContainers(fn Filter) ([]Container, error) {
 	return cs, nil
 }
 
+func (client dockerClient) createListFilter() filters.Args {
+	filterArgs := filters.NewArgs()
+	filterArgs.Add("status", "running")
+
+	if client.includeStopped {
+		filterArgs.Add("status", "created")
+		filterArgs.Add("status", "exited")
+	}
+
+	return filterArgs
+}
+
 func (client dockerClient) StopContainer(c Container, timeout time.Duration) error {
 	bg := context.Background()
 	signal := c.StopSignal()
@@ -90,11 +116,12 @@ func (client dockerClient) StopContainer(c Container, timeout time.Duration) err
 		signal = defaultStopSignal
 	}
 
+	if c.IsRunning() {
 		log.Infof("Stopping %s (%s) with %s", c.Name(), c.ID(), signal)
-
 		if err := client.api.ContainerKill(bg, c.ID(), signal); err != nil {
 			return err
 		}
+	}
 
 	// Wait for container to exit, but proceed anyway after the timeout elapses
 	client.waitForStop(c, timeout)
@@ -160,15 +187,23 @@ func (client dockerClient) StartContainer(c Container) error {
 
 	}
 
-	log.Debugf("Starting container %s (%s)", name, creation.ID)
+	return client.startContainerIfPreviouslyRunning(bg, c, creation)
 
-	err = client.api.ContainerStart(bg, creation.ID, types.ContainerStartOptions{})
-	if err != nil {
-		return err
 }
 
+func (client dockerClient) startContainerIfPreviouslyRunning(bg context.Context, c Container, creation container.ContainerCreateCreatedBody) error {
+	name := c.Name()
+
+	if !c.IsRunning() {
 		return nil
+	}
 
+	log.Debugf("Starting container %s (%s)", name, creation.ID)
+	err := client.api.ContainerStart(bg, creation.ID, types.ContainerStartOptions{})
+	if err != nil {
+		return err
+	}
+	return nil
 }
 
 func (client dockerClient) RenameContainer(c Container, newName string) error {

container/container.go

@@ -38,6 +38,13 @@ func (c Container) ID() string {
 	return c.containerInfo.ID
 }
 
+// IsRunning returns a boolean flag indicating whether or not the current
+// container is running. The status is determined by the value of the
+// container's "State.Running" property.
+func (c Container) IsRunning() bool {
+	return c.containerInfo.State.Running
+}
+
 // Name returns the Docker container name.
 func (c Container) Name() string {
 	return c.containerInfo.Name

container/container_test.go

@@ -17,15 +17,16 @@ func TestContainer(t *testing.T) {
 
 var _ = Describe("the container", func() {
 	Describe("the client", func() {
+		var docker *cli.Client
 		var client Client
 		BeforeSuite(func() {
 			server := mocks.NewMockAPIServer()
-			c, _ := cli.NewClientWithOpts(
+			docker, _ = cli.NewClientWithOpts(
 				cli.WithHost(server.URL),
 				cli.WithHTTPClient(server.Client(),
 				))
 			client = dockerClient{
-				api: c,
+				api:        docker,
 				pullImages: false,
 			}
 		})
@@ -55,6 +56,18 @@ var _ = Describe("the container", func() {
 				Expect(containers[0].ImageName()).To(Equal("containrrr/watchtower:latest"))
 			})
 		})
+		When(`listing containers with the "include stopped" option`, func() {
+			It("should return both stopped and running containers", func() {
+				client = dockerClient{
+					api:            docker,
+					pullImages:     false,
+					includeStopped: true,
+				}
+				containers, err := client.ListContainers(noFilter)
+				Expect(err).NotTo(HaveOccurred())
+				Expect(len(containers) > 0).To(BeTrue())
+			})
+		})
 	})
 	When("asked for metadata", func() {
 		var c *Container

container/mocks/ApiServer.go

@@ -18,7 +18,11 @@ func NewMockAPIServer() *httptest.Server {
 			logrus.Debug("Mock server has received a HTTP call on ", r.URL)
 			var response = ""
 
-			if  isRequestFor("containers/json?limit=0", r) {
+			if isRequestFor("filters=%7B%22status%22%3A%7B%22running%22%3Atrue%7D%7D&limit=0", r) {
+				response = getMockJSONFromDisk("./mocks/data/containers.json")
+			} else if isRequestFor("filters=%7B%22status%22%3A%7B%22created%22%3Atrue%2C%22exited%22%3Atrue%2C%22running%22%3Atrue%7D%7D&limit=0", r) {
+				response = getMockJSONFromDisk("./mocks/data/containers.json")
+			} else if isRequestFor("containers/json?limit=0", r) {
 				response = getMockJSONFromDisk("./mocks/data/containers.json")
 			} else if isRequestFor("ae8964ba86c7cd7522cf84e09781343d88e0e3543281c747d88b27e246578b65", r) {
 				response = getMockJSONFromDisk("./mocks/data/container_stopped.json")
@@ -48,4 +52,3 @@ func getMockJSONFromDisk(relPath string) string {
 	}
 	return string(buf)
 }
-

container/mocks/data/containers.json

@@ -12,7 +12,7 @@
     "Labels": {
       "com.centurylinklabs.watchtower": "true"
     },
-    "State": "exited",
+    "State": "running",
     "Status": "Exited (1) 6 days ago",
     "HostConfig": {
       "NetworkMode": "default"

main.go

@@ -89,7 +89,10 @@ func before(c *cli.Context) error {
 		return err
 	}
 
-	client = container.NewClient(!c.GlobalBool("no-pull"))
+	client = container.NewClient(
+		!c.GlobalBool("no-pull"),
+		c.GlobalBool("include-stopped"),
+	)
 	notifier = notifications.NewNotifier(c)
 
 	return nil