feat: filter containers seen by docker-gen

Author: buchdag

README.md

@@ -120,6 +120,11 @@ Options:
       only include containers with published ports (implies -only-exposed)
   -include-stopped
       include stopped containers
+  -container-filter
+      container filter for inclusion by docker-gen (e.g -container-filter status=running).
+      Using this option bypass the -include-stopped option and set it to true.
+      You can pass this option multiple times to combine filters with AND.
+      https://docs.docker.com/engine/reference/commandline/ps/#filter
   -tlscacert string
       path to TLS CA certificate file (default "~/.docker/machine/machines/default/ca.pem")
   -tlscert string

cmd/docker-gen/main.go

@@ -34,6 +34,7 @@ var (
 	onlyExposed           bool
 	onlyPublished         bool
 	includeStopped        bool
+	containerFilter       mapstringslice = make(mapstringslice)
 	configFiles           stringslice
 	configs               config.ConfigFile
 	interval              int
@@ -110,6 +111,8 @@ func initFlags() {
 	flag.BoolVar(&onlyPublished, "only-published", false,
 		"only include containers with published ports (implies -only-exposed)")
 	flag.BoolVar(&includeStopped, "include-stopped", false, "include stopped containers")
+	flag.Var(&containerFilter, "container-filter",
+		"container filter for inclusion by docker-gen. Using this option bypass the -include-stopped option and set it to true. You can pass this option multiple times to combine filters with AND. https://docs.docker.com/engine/reference/commandline/ps/#filter")
 	flag.BoolVar(&notifyOutput, "notify-output", false, "log the output(stdout/stderr) of notify command")
 	flag.StringVar(&notifyCmd, "notify", "", "run command after template is regenerated (e.g `restart xyz`)")
 	flag.Var(&sighupContainerID, "notify-sighup",
@@ -175,7 +178,7 @@ func main() {
 			NotifyContainers: make(map[string]int),
 			OnlyExposed:      onlyExposed,
 			OnlyPublished:    onlyPublished,
-			IncludeStopped:   includeStopped,
+			ContainerFilter:  containerFilter,
 			Interval:         interval,
 			KeepBlankLines:   keepBlankLines,
 		}
@@ -189,25 +192,20 @@ func main() {
 			cfg.NotifyContainersFilter = notifyContainerFilter
 			cfg.NotifyContainersSignal = notifyContainerSignal
 		}
+		if len(containerFilter) == 0 && !includeStopped {
+			cfg.ContainerFilter = map[string][]string{"status": {"running"}}
+		}
 		configs = config.ConfigFile{
 			Config: []config.Config{cfg},
 		}
 	}
 
-	all := false
-	for _, config := range configs.Config {
-		if config.IncludeStopped {
-			all = true
-		}
-	}
-
 	generator, err := generator.NewGenerator(generator.GeneratorConfig{
 		Endpoint:   endpoint,
 		TLSKey:     tlsKey,
 		TLSCert:    tlsCert,
 		TLSCACert:  tlsCaCert,
 		TLSVerify:  tlsVerify,
-		All:        all,
 		ConfigFile: configs,
 	})
 

internal/config/config.go

@@ -18,7 +18,7 @@ type Config struct {
 	NotifyContainersSignal int
 	OnlyExposed            bool
 	OnlyPublished          bool
-	IncludeStopped         bool
+	ContainerFilter        map[string][]string
 	Interval               int
 	KeepBlankLines         bool
 }

internal/generator/generator.go

@@ -38,7 +38,6 @@ type GeneratorConfig struct {
 	TLSKey    string
 	TLSCACert string
 	TLSVerify bool
-	All       bool
 
 	ConfigFile config.ConfigFile
 }
@@ -69,7 +68,6 @@ func NewGenerator(gc GeneratorConfig) (*generator, error) {
 		TLSCert:   gc.TLSCert,
 		TLSCaCert: gc.TLSCACert,
 		TLSKey:    gc.TLSKey,
-		All:       gc.All,
 		Configs:   gc.ConfigFile,
 		retry:     true,
 	}, nil
@@ -120,12 +118,13 @@ func (g *generator) generateFromSignals() {
 }
 
 func (g *generator) generateFromContainers() {
-	containers, err := g.getContainers()
-	if err != nil {
-		log.Printf("Error listing containers: %s\n", err)
-		return
-	}
 	for _, config := range g.Configs.Config {
+		containers, err := g.getContainers(config)
+		if err != nil {
+			log.Printf("Error listing containers: %s\n", err)
+			return
+		}
+
 		changed := template.GenerateFile(config, containers)
 		if !changed {
 			log.Printf("Contents of %s did not change. Skipping notification '%s'", config.Dest, config.NotifyCmd)
@@ -155,7 +154,7 @@ func (g *generator) generateAtInterval() {
 			for {
 				select {
 				case <-ticker.C:
-					containers, err := g.getContainers()
+					containers, err := g.getContainers(cfg)
 					if err != nil {
 						log.Printf("Error listing containers: %s\n", err)
 						continue
@@ -201,7 +200,7 @@ func (g *generator) generateFromEvents() {
 			defer g.wg.Done()
 			debouncedChan := newDebounceChannel(watcher, cfg.Wait)
 			for range debouncedChan {
-				containers, err := g.getContainers()
+				containers, err := g.getContainers(cfg)
 				if err != nil {
 					log.Printf("Error listing containers: %s\n", err)
 					continue
@@ -382,7 +381,7 @@ func (g *generator) sendSignalToFilteredContainers(config config.Config) {
 	}
 }
 
-func (g *generator) getContainers() ([]*context.RuntimeContainer, error) {
+func (g *generator) getContainers(config config.Config) ([]*context.RuntimeContainer, error) {
 	apiInfo, err := g.Client.Info()
 	if err != nil {
 		log.Printf("Error retrieving docker server info: %s\n", err)
@@ -391,8 +390,9 @@ func (g *generator) getContainers() ([]*context.RuntimeContainer, error) {
 	}
 
 	apiContainers, err := g.Client.ListContainers(docker.ListContainersOptions{
-		All:  g.All,
-		Size: false,
+		All:     true,
+		Size:    false,
+		Filters: config.ContainerFilter,
 	})
 	if err != nil {
 		return nil, err

internal/template/template.go

@@ -149,37 +149,22 @@ func removeBlankLines(reader io.Reader, writer io.Writer) {
 	bwriter.Flush()
 }
 
-func filterRunning(config config.Config, containers context.Context) context.Context {
-	if config.IncludeStopped {
-		return containers
-	} else {
-		filteredContainers := context.Context{}
-		for _, container := range containers {
-			if container.State.Running {
-				filteredContainers = append(filteredContainers, container)
-			}
-		}
-		return filteredContainers
-	}
-}
-
 func GenerateFile(config config.Config, containers context.Context) bool {
-	filteredRunningContainers := filterRunning(config, containers)
 	filteredContainers := context.Context{}
 	if config.OnlyPublished {
-		for _, container := range filteredRunningContainers {
+		for _, container := range containers {
 			if len(container.PublishedAddresses()) > 0 {
 				filteredContainers = append(filteredContainers, container)
 			}
 		}
 	} else if config.OnlyExposed {
-		for _, container := range filteredRunningContainers {
+		for _, container := range containers {
 			if len(container.Addresses) > 0 {
 				filteredContainers = append(filteredContainers, container)
 			}
 		}
 	} else {
-		filteredContainers = filteredRunningContainers
+		filteredContainers = containers
 	}
 
 	contents := executeTemplate(config.Template, filteredContainers)