fix: add fields such as CONTAINER_NAME to journald log entries sent t…

…o by containers

In the current implementation, containers running by `nerdctl` dose not
export entries containing fields such as `CONTAINER_NAME`, `IMAGE_NAME`
, and etc to the journald log like containers running by `docker cli`.

At this time, the journald log entry describes below when sending to the
journald log using nerdctl.

```
> nerdctl run -d --name nginx-nerdctl --log-driver=journald nginx
bb7df47d27fd73426cec286ed88c5abf1443e74df637e2440d2dbca7229a84dc

> nerdctl ps
CONTAINER ID    IMAGE                             COMMAND                   CREATED          STATUS    PORTS    NAMES
bb7df47d27fd    docker.io/library/nginx:latest    "/docker-entrypoint.…"    3 seconds ago    Up                 nginx-nerdctl

> sudo journalctl SYSLOG_IDENTIFIER=bb7df47d27fd -a -n 1 -o json-pretty
{
        "__CURSOR" : "???",
        "__REALTIME_TIMESTAMP" : "1730899940827182",
        "__MONOTONIC_TIMESTAMP" : "10815937979908",
        "_BOOT_ID" : "???",
        "_UID" : "0",
        "_GID" : "0",
        "_CAP_EFFECTIVE" : "1ffffffffff",
        "_MACHINE_ID" : "???",
        "_HOSTNAME" : "???.us-west-2.amazon.com",
        "_TRANSPORT" : "journal",
        "_SYSTEMD_SLICE" : "system.slice",
        "PRIORITY" : "3",
        "_SYSTEMD_CGROUP" : "/system.slice/containerd.service",
        "_SYSTEMD_UNIT" : "containerd.service",
        "_COMM" : "nerdctl",
        "_EXE" : "/usr/local/bin/nerdctl",
        "_CMDLINE" : "/usr/local/bin/nerdctl _NERDCTL_INTERNAL_LOGGING /var/lib/nerdctl/1935db59",
        "SYSLOG_IDENTIFIER" : "bb7df47d27fd",
        "_PID" : "8118",
        "MESSAGE" : "2024/11/06 13:32:20 [notice] 1#1: start worker process 44",
        "_SOURCE_REALTIME_TIMESTAMP" : "1730899940825905"
}
```

On the other hand, the output fields are listed below when we use the
journald logging driver with docker cli.

- https://docs.docker.com/engine/logging/drivers/journald/

As you can see, some entries are not output by nerdctl and are
incompatible with the docker cli.

This feature request is reported in the following:

- #3486

Therefore, in this pull request, we will add the fields to be output in
the journald log.

After applying this fix, the journald log will output the following
fields.

```
{
  "__CURSOR": "???",
  "__REALTIME_TIMESTAMP": "1731385591671422",
  "__MONOTONIC_TIMESTAMP": "11301588824148",
  "_BOOT_ID": "???",
  "_MACHINE_ID": "???",
  "_HOSTNAME": "???.us-west-2.amazon.com",
  "PRIORITY": "3",
  "_TRANSPORT": "journal",
  "_UID": "0",
  "_GID": "0",
  "_COMM": "nerdctl",
  "_EXE": "/usr/local/bin/nerdctl",
  "_CMDLINE": "/usr/local/bin/nerdctl _NERDCTL_INTERNAL_LOGGING /var/lib/nerdctl/1935db59",
  "_CAP_EFFECTIVE": "1ffffffffff",
  "_SYSTEMD_CGROUP": "/system.slice/containerd.service",
  "_SYSTEMD_UNIT": "containerd.service",
  "_SYSTEMD_SLICE": "system.slice",
  "CONTAINER_NAME": "nginx-nerdctl",
  "IMAGE_NAME": "nginx",
  "CONTAINER_ID_FULL": "fe22eccbd704ba799785999079ac465ed067d5914e9e3f1020e769921d5a83c5",
  "SYSLOG_IDENTIFIER": "fe22eccbd704",
  "CONTAINER_TAG": "fe22eccbd704",
  "CONTAINER_ID": "fe22eccbd704",
  "_PID": "31643",
  "MESSAGE": "2024/11/12 04:26:31 [notice] 1#1: start worker process 44",
  "_SOURCE_REALTIME_TIMESTAMP": "1731385591669765"
}
```

Signed-off-by: Hayato Kiwata <haytok@amazon.co.jp>

cmd/nerdctl/container/container_run_test.go

@@ -35,6 +35,7 @@ import (
 	"gotest.tools/v3/poll"
 
 	"github.com/containerd/nerdctl/v2/cmd/nerdctl/helpers"
+	"github.com/containerd/nerdctl/v2/pkg/logging"
 	"github.com/containerd/nerdctl/v2/pkg/testutil"
 	"github.com/containerd/nerdctl/v2/pkg/testutil/nerdtest"
 )
@@ -329,19 +330,44 @@ func TestRunWithJournaldLogDriver(t *testing.T) {
 	time.Sleep(3 * time.Second)
 	journalctl, err := exec.LookPath("journalctl")
 	assert.NilError(t, err)
+
 	inspectedContainer := base.InspectContainer(containerName)
-	found := 0
-	check := func(log poll.LogT) poll.Result {
-		res := icmd.RunCmd(icmd.Command(journalctl, "--no-pager", "--since", "2 minutes ago", fmt.Sprintf("SYSLOG_IDENTIFIER=%s", inspectedContainer.ID[:12])))
-		assert.Equal(t, 0, res.ExitCode, res)
-		if strings.Contains(res.Stdout(), "bar") && strings.Contains(res.Stdout(), "foo") {
-			found = 1
-			return poll.Success()
-		}
-		return poll.Continue("reading from journald is not yet finished")
+
+	type testCase struct {
+		name   string
+		filter string
+	}
+	testCases := []testCase{
+		{
+			name:   "filter using SYSLOG_IDENTIFIER field",
+			filter: fmt.Sprintf("SYSLOG_IDENTIFIER=%s", inspectedContainer.ID[:12]),
+		},
+		{
+			name:   "filter using CONTAINER_NAME field",
+			filter: fmt.Sprintf("CONTAINER_NAME=%s", containerName),
+		},
+		{
+			name:   "filter using IMAGE_NAME field",
+			filter: fmt.Sprintf("IMAGE_NAME=%s", logging.GetJournaldImageNameField(testutil.CommonImage)),
+		},
+	}
+	for _, tc := range testCases {
+		tc := tc
+		t.Run(tc.name, func(t *testing.T) {
+			found := 0
+			check := func(log poll.LogT) poll.Result {
+				res := icmd.RunCmd(icmd.Command(journalctl, "--no-pager", "--since", "2 minutes ago", tc.filter))
+				assert.Equal(t, 0, res.ExitCode, res)
+				if strings.Contains(res.Stdout(), "bar") && strings.Contains(res.Stdout(), "foo") {
+					found = 1
+					return poll.Success()
+				}
+				return poll.Continue("reading from journald is not yet finished")
+			}
+			poll.WaitOn(t, check, poll.WithDelay(100*time.Microsecond), poll.WithTimeout(20*time.Second))
+			assert.Equal(t, 1, found)
+		})
 	}
-	poll.WaitOn(t, check, poll.WithDelay(100*time.Microsecond), poll.WithTimeout(20*time.Second))
-	assert.Equal(t, 1, found)
 }
 
 func TestRunWithJournaldLogDriverAndLogOpt(t *testing.T) {

pkg/cmd/container/create.go

@@ -218,7 +218,7 @@ func Create(ctx context.Context, client *containerd.Client, args []string, netMa
 	// 1, nerdctl run --name demo -it imagename
 	// 2, ctrl + c to stop demo container
 	// 3, nerdctl start/restart demo
-	logConfig, err := generateLogConfig(dataStore, id, options.LogDriver, options.LogOpt, options.GOptions.Namespace)
+	logConfig, err := generateLogConfig(dataStore, id, options.LogDriver, options.LogOpt, options.GOptions.Namespace, options.GOptions.Address)
 	if err != nil {
 		return nil, generateRemoveStateDirFunc(ctx, id, internalLabels), err
 	}
@@ -819,12 +819,13 @@ func writeCIDFile(path, id string) error {
 }
 
 // generateLogConfig creates a LogConfig for the current container store
-func generateLogConfig(dataStore string, id string, logDriver string, logOpt []string, ns string) (logConfig logging.LogConfig, err error) {
+func generateLogConfig(dataStore string, id string, logDriver string, logOpt []string, ns, address string) (logConfig logging.LogConfig, err error) {
 	var u *url.URL
 	if u, err = url.Parse(logDriver); err == nil && u.Scheme != "" {
 		logConfig.LogURI = logDriver
 	} else {
 		logConfig.Driver = logDriver
+		logConfig.Address = address
 		logConfig.Opts, err = parseKVStringsMapFromLogOpt(logOpt, logDriver)
 		if err != nil {
 			return logConfig, err
@@ -834,7 +835,7 @@ func generateLogConfig(dataStore string, id string, logDriver string, logOpt []s
 			logConfigB    []byte
 			lu            *url.URL
 		)
-		logDriverInst, err = logging.GetDriver(logDriver, logConfig.Opts)
+		logDriverInst, err = logging.GetDriver(logDriver, logConfig.Opts, logConfig.Address)
 		if err != nil {
 			return logConfig, err
 		}

pkg/logging/journald_logger.go

@@ -18,6 +18,7 @@ package logging
 
 import (
 	"bytes"
+	"context"
 	"errors"
 	"fmt"
 	"io"
@@ -32,9 +33,13 @@ import (
 	"github.com/docker/cli/templates"
 	timetypes "github.com/docker/docker/api/types/time"
 
+	containerd "github.com/containerd/containerd/v2/client"
 	"github.com/containerd/containerd/v2/core/runtime/v2/logging"
 	"github.com/containerd/log"
 
+	"github.com/containerd/nerdctl/v2/pkg/clientutil"
+	"github.com/containerd/nerdctl/v2/pkg/containerutil"
+	"github.com/containerd/nerdctl/v2/pkg/imgutil"
 	"github.com/containerd/nerdctl/v2/pkg/strutil"
 )
 
@@ -52,8 +57,9 @@ func JournalLogOptsValidate(logOptMap map[string]string) error {
 }
 
 type JournaldLogger struct {
-	Opts map[string]string
-	vars map[string]string
+	Opts    map[string]string
+	vars    map[string]string
+	Address string
 }
 
 type identifier struct {
@@ -95,9 +101,38 @@ func (journaldLogger *JournaldLogger) PreProcess(dataStore string, config *loggi
 			syslogIdentifier = b.String()
 		}
 	}
+
+	ctx := context.Background()
+	client, ctx, cancel, err := clientutil.NewClient(ctx, config.Namespace, journaldLogger.Address)
+	if err != nil {
+		return err
+	}
+	defer func() {
+		cancel()
+		client.Close()
+	}()
+	containerID := config.ID
+	container, err := client.LoadContainer(ctx, containerID)
+	if err != nil {
+		return err
+	}
+	containerLabels, err := container.Labels(ctx)
+	if err != nil {
+		return err
+	}
+	info, err := container.Info(ctx, containerd.WithoutRefreshedMetadata)
+	if err != nil {
+		return err
+	}
+
 	// construct log metadata for the container
 	vars := map[string]string{
 		"SYSLOG_IDENTIFIER": syslogIdentifier,
+		"CONTAINER_TAG":     syslogIdentifier,
+		"CONTAINER_ID":      shortID,
+		"CONTAINER_ID_FULL": containerID,
+		"CONTAINER_NAME":    containerutil.GetContainerName(containerLabels),
+		"IMAGE_NAME":        GetJournaldImageNameField(info.Image),
 	}
 	journaldLogger.vars = vars
 	return nil
@@ -200,3 +235,12 @@ func prepareJournalCtlDate(t string) (string, error) {
 	s := tm.Format("2006-01-02 15:04:05")
 	return s, nil
 }
+
+func GetJournaldImageNameField(image string) string {
+	imageName := image
+	if repo, tag := imgutil.ParseRepoTag(imageName); tag == "latest" {
+		imageName = repo
+	}
+
+	return imageName
+}

pkg/logging/logging.go

@@ -54,7 +54,7 @@ type Driver interface {
 	PostProcess() error
 }
 
-type DriverFactory func(map[string]string) (Driver, error)
+type DriverFactory func(map[string]string, string) (Driver, error)
 type LogOptsValidateFunc func(logOptMap map[string]string) error
 
 var drivers = make(map[string]DriverFactory)
@@ -81,28 +81,28 @@ func Drivers() []string {
 	return ss
 }
 
-func GetDriver(name string, opts map[string]string) (Driver, error) {
+func GetDriver(name string, opts map[string]string, address string) (Driver, error) {
 	driverFactory, ok := drivers[name]
 	if !ok {
 		return nil, fmt.Errorf("unknown logging driver %q: %w", name, errdefs.ErrNotFound)
 	}
-	return driverFactory(opts)
+	return driverFactory(opts, address)
 }
 
 func init() {
-	RegisterDriver("none", func(opts map[string]string) (Driver, error) {
+	RegisterDriver("none", func(opts map[string]string, address string) (Driver, error) {
 		return &NoneLogger{}, nil
 	}, NoneLogOptsValidate)
-	RegisterDriver("json-file", func(opts map[string]string) (Driver, error) {
+	RegisterDriver("json-file", func(opts map[string]string, address string) (Driver, error) {
 		return &JSONLogger{Opts: opts}, nil
 	}, JSONFileLogOptsValidate)
-	RegisterDriver("journald", func(opts map[string]string) (Driver, error) {
-		return &JournaldLogger{Opts: opts}, nil
+	RegisterDriver("journald", func(opts map[string]string, address string) (Driver, error) {
+		return &JournaldLogger{Opts: opts, Address: address}, nil
 	}, JournalLogOptsValidate)
-	RegisterDriver("fluentd", func(opts map[string]string) (Driver, error) {
+	RegisterDriver("fluentd", func(opts map[string]string, address string) (Driver, error) {
 		return &FluentdLogger{Opts: opts}, nil
 	}, FluentdLogOptsValidate)
-	RegisterDriver("syslog", func(opts map[string]string) (Driver, error) {
+	RegisterDriver("syslog", func(opts map[string]string, address string) (Driver, error) {
 		return &SyslogLogger{Opts: opts}, nil
 	}, SyslogOptsValidate)
 }
@@ -121,9 +121,10 @@ func Main(argv2 string) error {
 
 // LogConfig is marshalled as "log-config.json"
 type LogConfig struct {
-	Driver string            `json:"driver"`
-	Opts   map[string]string `json:"opts,omitempty"`
-	LogURI string            `json:"-"`
+	Driver  string            `json:"driver"`
+	Opts    map[string]string `json:"opts,omitempty"`
+	LogURI  string            `json:"-"`
+	Address string            `json:"address"`
 }
 
 // LogConfigFilePath returns the path of log-config.json
@@ -215,7 +216,7 @@ func loggerFunc(dataStore string) (logging.LoggerFunc, error) {
 			if err != nil {
 				return err
 			}
-			driver, err := GetDriver(logConfig.Driver, logConfig.Opts)
+			driver, err := GetDriver(logConfig.Driver, logConfig.Opts, logConfig.Address)
 			if err != nil {
 				return err
 			}