docker info show logging driver info

Signed-off-by: Deng Guangxing <dengguangxing@huawei.com>

api/client/info.go

@@ -57,6 +57,9 @@ func (cli *DockerCli) CmdInfo(args ...string) error {
 	if remoteInfo.Exists("ExecutionDriver") {
 		fmt.Fprintf(cli.out, "Execution Driver: %s\n", remoteInfo.Get("ExecutionDriver"))
 	}
+	if remoteInfo.Exists("LoggingDriver") {
+		fmt.Fprintf(cli.out, "Logging Driver: %s\n", remoteInfo.Get("LoggingDriver"))
+	}
 	if remoteInfo.Exists("KernelVersion") {
 		fmt.Fprintf(cli.out, "Kernel Version: %s\n", remoteInfo.Get("KernelVersion"))
 	}

daemon/info.go

@@ -79,6 +79,7 @@ func (daemon *Daemon) CmdInfo(job *engine.Job) error {
 	v.SetInt("NGoroutines", runtime.NumGoroutine())
 	v.Set("SystemTime", time.Now().Format(time.RFC3339Nano))
 	v.Set("ExecutionDriver", daemon.ExecutionDriver().Name())
+	v.Set("LoggingDriver", daemon.defaultLogConfig.Type)
 	v.SetInt("NEventsListener", env.GetInt("count"))
 	v.Set("KernelVersion", kernelVersion)
 	v.Set("OperatingSystem", operatingSystem)

docs/man/docker-info.1.md

@@ -37,6 +37,7 @@ Here is a sample output:
      Root Dir: /var/lib/docker/aufs
      Dirs: 80
     Execution Driver: native-0.2
+    Logging Driver: json-file
     Kernel Version: 3.13.0-24-generic
     Operating System: Ubuntu 14.04 LTS
     CPUs: 1

docs/sources/reference/commandline/cli.md

@@ -1332,6 +1332,7 @@ For example:
      Backing Filesystem: extfs
      Dirs: 545
     Execution Driver: native-0.2
+    Logging Driver: json-file
     Kernel Version: 3.13.0-24-generic
     Operating System: Ubuntu 14.04 LTS
     CPUs: 1

docs/sources/userguide/labels-custom-metadata.md

@@ -171,6 +171,7 @@ These labels appear as part of the `docker info` output for the daemon:
      Backing Filesystem: extfs
      Dirs: 697
     Execution Driver: native-0.2
+    Logging Driver: json-file
     Kernel Version: 3.13.0-32-generic
     Operating System: Ubuntu 14.04.1 LTS
     CPUs: 1

integration-cli/docker_cli_info_test.go

@@ -14,7 +14,7 @@ func TestInfoEnsureSucceeds(t *testing.T) {
 		t.Fatalf("failed to execute docker info: %s, %v", out, err)
 	}
 
-	stringsToCheck := []string{"Containers:", "Execution Driver:", "Kernel Version:"}
+	stringsToCheck := []string{"Containers:", "Execution Driver:", "Logging Driver:", "Kernel Version:"}
 
 	for _, linePrefix := range stringsToCheck {
 		if !strings.Contains(out, linePrefix) {