Add filter for events emitted by docker daemon

This fix tries to cover the issue raised in #22463 by adding
filter for events emitted by docker daemon so that user could
utilize filter to receive events of interest.

Documentations have been updated for this fix.

Additional tests have been added to cover the changes in this fix.

This fix fixes #22463.

Signed-off-by: Yong Tang <yong.tang.github@outlook.com>

daemon/daemon.go

@@ -1393,6 +1393,8 @@ func (daemon *Daemon) Reload(config *Config) error {
 	} else {
 		attributes["labels"] = "[]"
 	}
+	attributes["max-concurrent-downloads"] = fmt.Sprintf("%d", *daemon.configStore.MaxConcurrentDownloads)
+	attributes["max-concurrent-uploads"] = fmt.Sprintf("%d", *daemon.configStore.MaxConcurrentUploads)
 	daemon.LogDaemonEventWithAttributes("reload", attributes)
 
 	return nil

daemon/events.go

@@ -83,6 +83,9 @@ func (daemon *Daemon) LogNetworkEventWithAttributes(nw libnetwork.Network, actio
 // LogDaemonEventWithAttributes generates an event related to the daemon itself with specific given attributes.
 func (daemon *Daemon) LogDaemonEventWithAttributes(action string, attributes map[string]string) {
 	if daemon.EventsService != nil {
+		if info, err := daemon.SystemInfo(); err == nil && info.Name != "" {
+			attributes["name"] = info.Name
+		}
 		actor := events.Actor{
 			ID:         daemon.ID,
 			Attributes: attributes,

daemon/events/filter.go

@@ -20,6 +20,7 @@ func NewFilter(filter filters.Args) *Filter {
 func (ef *Filter) Include(ev events.Message) bool {
 	return ef.filter.ExactMatch("event", ev.Action) &&
 		ef.filter.ExactMatch("type", ev.Type) &&
+		ef.matchDaemon(ev) &&
 		ef.matchContainer(ev) &&
 		ef.matchVolume(ev) &&
 		ef.matchNetwork(ev) &&
@@ -34,6 +35,10 @@ func (ef *Filter) matchLabels(attributes map[string]string) bool {
 	return ef.filter.MatchKVList("label", attributes)
 }
 
+func (ef *Filter) matchDaemon(ev events.Message) bool {
+	return ef.fuzzyMatchName(ev, events.DaemonEventType)
+}
+
 func (ef *Filter) matchContainer(ev events.Message) bool {
 	return ef.fuzzyMatchName(ev, events.ContainerEventType)
 }

docs/reference/api/docker_remote_api.md

@@ -119,7 +119,8 @@ This section lists each version from latest to oldest.  Each listing includes a
 * `POST /containers/create` now returns a HTTP 400 "bad parameter" message
   if no command is specified (instead of a HTTP 500 "server error")
 * `GET /images/search` now takes a `filters` query parameter.
-* `GET /events` now supports daemon events of `reload`.
+* `GET /events` now supports a `reload` event that is emitted when the daemon configuration is reloaded.
+* `GET /events` now supports filtering by daemon name or ID.
 
 ### v1.23 API changes
 

docs/reference/api/docker_remote_api_v1.24.md

@@ -2593,9 +2593,10 @@ Query Parameters:
   -   `event=<string>`; -- event to filter
   -   `image=<string>`; -- image to filter
   -   `label=<string>`; -- image and container label to filter
-  -   `type=<string>`; -- either `container` or `image` or `volume` or `network`
+  -   `type=<string>`; -- either `container` or `image` or `volume` or `network` or `daemon`
   -   `volume=<string>`; -- volume to filter
   -   `network=<string>`; -- network to filter
+  -   `daemon=<string>`; -- daemon name or id to filter
 
 Status Codes:
 

docs/reference/commandline/events.md

@@ -72,9 +72,10 @@ The currently supported filters are:
 * event (`event=<event action>`)
 * image (`image=<tag or id>`)
 * label (`label=<key>` or `label=<key>=<value>`)
-* type (`type=<container or image or volume or network>`)
+* type (`type=<container or image or volume or network or daemon>`)
 * volume (`volume=<name or id>`)
 * network (`network=<name or id>`)
+* daemon (`daemon=<name or id>`)
 
 ## Examples
 

integration-cli/docker_cli_events_unix_test.go

@@ -386,17 +386,19 @@ func (s *DockerDaemonSuite) TestDaemonEvents(c *check.C) {
 	out, err := s.d.Cmd("info")
 	c.Assert(err, checker.IsNil)
 	daemonID := ""
+	daemonName := ""
 	for _, line := range strings.Split(out, "\n") {
 		if strings.HasPrefix(line, "ID: ") {
 			daemonID = strings.TrimPrefix(line, "ID: ")
-			break
+		} else if strings.HasPrefix(line, "Name: ") {
+			daemonName = strings.TrimPrefix(line, "Name: ")
 		}
 	}
 	c.Assert(daemonID, checker.Not(checker.Equals), "")
 
 	configFile, err = os.Create(configFilePath)
 	c.Assert(err, checker.IsNil)
-	daemonConfig = `{"labels":["bar=foo"]}`
+	daemonConfig = `{"max-concurrent-downloads":1,"labels":["bar=foo"]}`
 	fmt.Fprintf(configFile, "%s", daemonConfig)
 	configFile.Close()
 
@@ -406,5 +408,58 @@ func (s *DockerDaemonSuite) TestDaemonEvents(c *check.C) {
 
 	out, err = s.d.Cmd("events", "--since=0", "--until", daemonUnixTime(c))
 	c.Assert(err, checker.IsNil)
-	c.Assert(out, checker.Contains, fmt.Sprintf("daemon reload %s (cluster-advertise=, cluster-store=, cluster-store-opts={}, debug=true, labels=[\"bar=foo\"])", daemonID))
+	c.Assert(out, checker.Contains, fmt.Sprintf("daemon reload %s (cluster-advertise=, cluster-store=, cluster-store-opts={}, debug=true, labels=[\"bar=foo\"], max-concurrent-downloads=1, max-concurrent-uploads=5, name=%s)", daemonID, daemonName))
+}
+
+func (s *DockerDaemonSuite) TestDaemonEventsWithFilters(c *check.C) {
+	testRequires(c, SameHostDaemon, DaemonIsLinux)
+
+	// daemon config file
+	configFilePath := "test.json"
+	configFile, err := os.Create(configFilePath)
+	c.Assert(err, checker.IsNil)
+	defer os.Remove(configFilePath)
+
+	daemonConfig := `{"labels":["foo=bar"]}`
+	fmt.Fprintf(configFile, "%s", daemonConfig)
+	configFile.Close()
+	c.Assert(s.d.Start(fmt.Sprintf("--config-file=%s", configFilePath)), check.IsNil)
+
+	// Get daemon ID
+	out, err := s.d.Cmd("info")
+	c.Assert(err, checker.IsNil)
+	daemonID := ""
+	daemonName := ""
+	for _, line := range strings.Split(out, "\n") {
+		if strings.HasPrefix(line, "ID: ") {
+			daemonID = strings.TrimPrefix(line, "ID: ")
+		} else if strings.HasPrefix(line, "Name: ") {
+			daemonName = strings.TrimPrefix(line, "Name: ")
+		}
+	}
+	c.Assert(daemonID, checker.Not(checker.Equals), "")
+
+	syscall.Kill(s.d.cmd.Process.Pid, syscall.SIGHUP)
+
+	time.Sleep(3 * time.Second)
+
+	out, err = s.d.Cmd("events", "--since=0", "--until", daemonUnixTime(c), "--filter", fmt.Sprintf("daemon=%s", daemonID))
+	c.Assert(err, checker.IsNil)
+	c.Assert(out, checker.Contains, fmt.Sprintf("daemon reload %s", daemonID))
+
+	out, err = s.d.Cmd("events", "--since=0", "--until", daemonUnixTime(c), "--filter", fmt.Sprintf("daemon=%s", daemonName))
+	c.Assert(err, checker.IsNil)
+	c.Assert(out, checker.Contains, fmt.Sprintf("daemon reload %s", daemonID))
+
+	out, err = s.d.Cmd("events", "--since=0", "--until", daemonUnixTime(c), "--filter", "daemon=foo")
+	c.Assert(err, checker.IsNil)
+	c.Assert(out, checker.Not(checker.Contains), fmt.Sprintf("daemon reload %s", daemonID))
+
+	out, err = s.d.Cmd("events", "--since=0", "--until", daemonUnixTime(c), "--filter", "type=daemon")
+	c.Assert(err, checker.IsNil)
+	c.Assert(out, checker.Contains, fmt.Sprintf("daemon reload %s", daemonID))
+
+	out, err = s.d.Cmd("events", "--since=0", "--until", daemonUnixTime(c), "--filter", "type=container")
+	c.Assert(err, checker.IsNil)
+	c.Assert(out, checker.Not(checker.Contains), fmt.Sprintf("daemon reload %s", daemonID))
 }