Add support for notifying a service

GLOCKFILE

@@ -1,2 +1,2 @@
 github.com/BurntSushi/toml 056c9bc7be7190eaa7715723883caffa5f8fa3e4
-github.com/fsouza/go-dockerclient e0d22d30691bcc996eca51f729a4777b8c7dc2a8
+github.com/fsouza/go-dockerclient 4bc6a18363f79b32c26f92e2e6d8bfd30d79a770

cmd/docker-gen/main.go

@@ -23,6 +23,7 @@ var (
 	notifyCmd               string
 	notifyOutput            bool
 	notifySigHUPContainerID string
+	notifySigHUPServiceID   string
 	onlyExposed             bool
 	onlyPublished           bool
 	includeStopped          bool
@@ -97,6 +98,7 @@ func initFlags() {
 	flag.StringVar(&notifyCmd, "notify", "", "run command after template is regenerated (e.g `restart xyz`)")
 	flag.StringVar(&notifySigHUPContainerID, "notify-sighup", "",
 		"send HUP signal to container.  Equivalent to `docker kill -s HUP container-ID`")
+	flag.StringVar(&notifySigHUPServiceID, "service-notify-sighup", "", "send HUP signal to all containers belong to a service.")
 	flag.Var(&configFiles, "config", "config files with template directives. Config files will be merged if this option is specified multiple times.")
 	flag.IntVar(&interval, "interval", 0, "notify command interval (secs)")
 	flag.BoolVar(&keepBlankLines, "keep-blank-lines", false, "keep blank lines in the output file")
@@ -143,6 +145,7 @@ func main() {
 			NotifyCmd:        notifyCmd,
 			NotifyOutput:     notifyOutput,
 			NotifyContainers: make(map[string]docker.Signal),
+			NotifyServices:   make(map[string]docker.Signal),
 			OnlyExposed:      onlyExposed,
 			OnlyPublished:    onlyPublished,
 			IncludeStopped:   includeStopped,
@@ -152,6 +155,9 @@ func main() {
 		if notifySigHUPContainerID != "" {
 			config.NotifyContainers[notifySigHUPContainerID] = docker.SIGHUP
 		}
+		if notifySigHUPServiceID != "" {
+			config.NotifyServices[notifySigHUPServiceID] = docker.SIGHUP
+		}
 		configs = dockergen.ConfigFile{
 			Config: []dockergen.Config{config}}
 	}

config.go

@@ -16,6 +16,7 @@ type Config struct {
 	NotifyCmd        string
 	NotifyOutput     bool
 	NotifyContainers map[string]docker.Signal
+	NotifyServices   map[string]docker.Signal
 	OnlyExposed      bool
 	OnlyPublished    bool
 	IncludeStopped   bool

context.go

@@ -27,13 +27,13 @@ func (c *Context) Docker() Docker {
 	return dockerInfo
 }
 
-func SetServerInfo(d *docker.Env) {
+func SetServerInfo(d *docker.DockerInfo) {
 	mu.Lock()
 	defer mu.Unlock()
 	dockerInfo = Docker{
-		Name:               d.Get("Name"),
-		NumContainers:      d.GetInt("Containers"),
-		NumImages:          d.GetInt("Images"),
+		Name:               d.Name,
+		NumContainers:      d.Containers,
+		NumImages:          d.Images,
 		Version:            dockerEnv.Get("Version"),
 		ApiVersion:         dockerEnv.Get("ApiVersion"),
 		GoVersion:          dockerEnv.Get("GoVersion"),

generator.go

@@ -127,6 +127,7 @@ func (g *generator) generateFromContainers() {
 		}
 		g.runNotifyCmd(config)
 		g.sendSignalToContainer(config)
+		g.sendSignalToService(config)
 	}
 }
 
@@ -156,6 +157,7 @@ func (g *generator) generateAtInterval() {
 					GenerateFile(config, containers)
 					g.runNotifyCmd(config)
 					g.sendSignalToContainer(config)
+					g.sendSignalToService(config)
 				case sig := <-sigChan:
 					log.Printf("Received signal: %s\n", sig)
 					switch sig {
@@ -204,6 +206,7 @@ func (g *generator) generateFromEvents() {
 				}
 				g.runNotifyCmd(config)
 				g.sendSignalToContainer(config)
+				g.sendSignalToService(config)
 			}
 		}(config, make(chan *docker.APIEvents, 100))
 	}
@@ -341,6 +344,37 @@ func (g *generator) sendSignalToContainer(config Config) {
 	}
 }
 
+func (g *generator) sendSignalToService(config Config) {
+	if len(config.NotifyServices) < 1 {
+		return
+	}
+
+	for service, signal := range config.NotifyServices {
+		log.Printf("Service '%s' needs notification", service)
+		taskOpts := docker.ListTasksOptions{
+			Filters: map[string][]string{
+				"service": []string{service},
+			},
+		}
+		tasks, err := g.Client.ListTasks(taskOpts)
+		if err != nil {
+			log.Printf("Error retrieving task list: %s", err)
+		}
+		for _, task := range tasks {
+			container := task.Status.ContainerStatus.ContainerID
+
+			log.Printf("Sending container '%s' signal '%v'", container, signal)
+			killOpts := docker.KillContainerOptions{
+				ID:     container,
+				Signal: signal,
+			}
+			if err := g.Client.KillContainer(killOpts); err != nil {
+				log.Printf("Error sending signal to container: %s", err)
+			}
+		}
+	}
+}
+
 func (g *generator) getContainers() ([]*RuntimeContainer, error) {
 	apiInfo, err := g.Client.Info()
 	if err != nil {