impl: filtering

based off of mcuadros#212

README.md

@@ -122,6 +122,29 @@ docker run -it --rm \
         nginx
 ```
 
+**Ofelia** reads labels of all Docker containers for configuration by default. To apply on a subset of containers only, use the flag `--docker-filter` (or `-f`) similar to the [filtering for `docker ps`](https://docs.docker.com/engine/reference/commandline/ps/#filter). E.g. to apply to current docker compose project only using `label` filter:
+
+```yaml
+version: "3"
+services:
+  ofelia:
+    image: mcuadros/ofelia:latest
+    depends_on:
+      - nginx
+    command: daemon --docker -f label=com.docker.compose.project=${COMPOSE_PROJECT_NAME}
+    volumes:
+      - /var/run/docker.sock:/var/run/docker.sock:ro
+    labels:
+      ofelia.job-local.my-test-job.schedule: "@every 5s"
+      ofelia.job-local.my-test-job.command: "date"
+  nginx:
+    image: nginx
+    labels:
+      ofelia.enabled: "true"
+      ofelia.job-exec.datecron.schedule: "@every 5s"
+      ofelia.job-exec.datecron.command: "uname -a"
+```
+
 ### Dynamic Docker configuration
 
 You can start Ofelia in its own container or on the host itself, and it will magically pick up any container that starts, stops or is modified on the fly.

cli/config.go

@@ -27,6 +27,7 @@ type Config struct {
 	RunJobs       map[string]*RunJobConfig     `gcfg:"job-run" mapstructure:"job-run,squash"`
 	ServiceJobs   map[string]*RunServiceConfig `gcfg:"job-service-run" mapstructure:"job-service-run,squash"`
 	LocalJobs     map[string]*LocalJobConfig   `gcfg:"job-local" mapstructure:"job-local,squash"`
+	Docker        DockerConfig
 	sh            *core.Scheduler
 	dockerHandler *DockerHandler
 	logger        core.Logger
@@ -67,24 +68,29 @@ func (c *Config) InitializeApp() error {
 	c.buildSchedulerMiddlewares(c.sh)
 
 	var err error
-	c.dockerHandler, err = NewDockerHandler(c, c.logger)
+	c.dockerHandler, err = NewDockerHandler(c, c.logger, c.Docker.Filters)
 	if err != nil {
 		return err
 	}
 
 	// In order to support non dynamic job types such as Local or Run using labels
 	// lets parse the labels and merge the job lists
 	dockerLabels, err := c.dockerHandler.GetDockerLabels()
-	var parsedLabelConfig Config
-	parsedLabelConfig.buildFromDockerLabels(dockerLabels)
-	for name, j := range parsedLabelConfig.RunJobs {
-		c.RunJobs[name] = j
-	}
-	for name, j := range parsedLabelConfig.LocalJobs {
-		c.LocalJobs[name] = j
-	}
-	for name, j := range parsedLabelConfig.ServiceJobs {
-		c.ServiceJobs[name] = j
+	if err == nil {
+		parsedLabelConfig := Config{}
+
+		parsedLabelConfig.buildFromDockerLabels(dockerLabels)
+		for name, j := range parsedLabelConfig.RunJobs {
+			c.RunJobs[name] = j
+		}
+
+		for name, j := range parsedLabelConfig.LocalJobs {
+			c.LocalJobs[name] = j
+		}
+
+		for name, j := range parsedLabelConfig.ServiceJobs {
+			c.ServiceJobs[name] = j
+		}
 	}
 
 	for name, j := range c.ExecJobs {
@@ -297,3 +303,7 @@ func (c *RunServiceConfig) buildMiddlewares() {
 	c.RunServiceJob.Use(middlewares.NewSave(&c.SaveConfig))
 	c.RunServiceJob.Use(middlewares.NewMail(&c.MailConfig))
 }
+
+type DockerConfig struct {
+	Filters []string `mapstructure:"filters"`
+}

cli/daemon.go

@@ -10,11 +10,13 @@ import (
 
 // DaemonCommand daemon process
 type DaemonCommand struct {
-	ConfigFile string `long:"config" description:"configuration file" default:"/etc/ofelia.conf"`
-	scheduler  *core.Scheduler
-	signals    chan os.Signal
-	done       chan bool
-	Logger     core.Logger
+	ConfigFile    string   `long:"config" description:"configuration file" default:"/etc/ofelia.conf"`
+	DockerFilters []string `short:"f" long:"docker-filter" description:"Filter for docker containers"`
+
+	scheduler *core.Scheduler
+	signals   chan os.Signal
+	done      chan bool
+	Logger    core.Logger
 }
 
 // Execute runs the daemon

cli/docker_config_handler.go

@@ -12,6 +12,7 @@ import (
 var ErrNoContainerWithOfeliaEnabled = errors.New("Couldn't find containers with label 'ofelia.enabled=true'")
 
 type DockerHandler struct {
+	filters      []string
 	dockerClient *docker.Client
 	notifier     dockerLabelsUpdate
 	logger       core.Logger
@@ -35,18 +36,21 @@ func (c *DockerHandler) buildDockerClient() (*docker.Client, error) {
 	return d, nil
 }
 
-func NewDockerHandler(notifier dockerLabelsUpdate, logger core.Logger) (*DockerHandler, error) {
-	c := &DockerHandler{}
+func NewDockerHandler(notifier dockerLabelsUpdate, logger core.Logger, filters []string) (*DockerHandler, error) {
+	c := &DockerHandler{
+		filters:  filters,
+		notifier: notifier,
+		logger:   logger,
+	}
+
 	var err error
 	c.dockerClient, err = c.buildDockerClient()
-	c.notifier = notifier
-	c.logger = logger
 	if err != nil {
 		return nil, err
 	}
+
 	// Do a sanity check on docker
-	_, err = c.dockerClient.Info()
-	if err != nil {
+	if _, err = c.dockerClient.Info(); err != nil {
 		return nil, err
 	}
 
@@ -71,10 +75,25 @@ func (c *DockerHandler) watch() {
 }
 
 func (c *DockerHandler) GetDockerLabels() (map[string]map[string]string, error) {
+	filters := map[string][]string{
+		"label": {requiredLabelFilter},
+	}
+	for _, f := range c.filters {
+		parts := strings.SplitN(f, "=", 2)
+		if len(parts) != 2 {
+			return nil, errors.New("invalid docker filter: " + f)
+		}
+		key, value := parts[0], parts[1]
+		values, ok := filters[key]
+		if ok {
+			filters[key] = append(values, value)
+		} else {
+			filters[key] = []string{value}
+		}
+	}
+
 	conts, err := c.dockerClient.ListContainers(docker.ListContainersOptions{
-		Filters: map[string][]string{
-			"label": {requiredLabelFilter},
-		},
+		Filters: filters,
 	})
 	if err != nil {
 		return nil, err