Merge pull request #187 from yohamta/feat/scheduler-log-rotation

feat: scheduler log rotation

README.md

@@ -45,6 +45,7 @@ It runs [DAGs (Directed acyclic graph)](https://en.wikipedia.org/wiki/Directed_a
   - [Admin Configuration](#admin-configuration)
     - [Environment Variables](#environment-variables-1)
     - [Web UI Configuration](#web-ui-configuration)
+    - [Scheduler Log](#scheduler-log)
     - [Global Configuration](#global-configuration)
   - [REST API Interface](#rest-api-interface)
   - [FAQ](#faq)
@@ -405,6 +406,14 @@ basicAuthUsername: <username for basic auth of web UI>       # [optional] basic
 basicAuthPassword: <password for basic auth of web UI>       # [optional] basic auth config
 ```
 
+### Scheduler Log
+
+The default path is `~/.dagu/logs/`. If you want to change this, you can set `log` field in `~/.dagu/admin.yaml`.
+
+```yaml
+logs: <path-to-log-files-for-scheduler>
+```
+
 ### Global Configuration
 
 Creating a global configuration `~/.dagu/config.yaml` is a convenient way to organize shared settings.

internal/logger/simple.go

@@ -0,0 +1,101 @@
+package logger
+
+import (
+	"fmt"
+	"io"
+	"os"
+	"path"
+	"sync"
+	"time"
+
+	"github.com/yohamta/dagu/internal/utils"
+)
+
+type SimpleLogger struct {
+	Dir     string
+	LogName string
+	Period  time.Duration
+	mu      sync.Mutex
+	file    *os.File
+	stop    chan struct{}
+}
+
+var _ io.Writer = (*SimpleLogger)(nil)
+
+func NewSimpleLogger(dir, logName string, period time.Duration) *SimpleLogger {
+	return &SimpleLogger{
+		Dir:     dir,
+		LogName: logName,
+		Period:  period,
+		stop:    make(chan struct{}),
+	}
+}
+
+func (rl *SimpleLogger) Open() error {
+	err := rl.setupFile()
+	if err != nil {
+		return err
+	}
+	go func() {
+		timer := time.NewTimer(time.Until(rl.timeToSwitchLog()))
+		for {
+			select {
+			case <-timer.C:
+				rl.mu.Lock()
+				err := rl.setupFile()
+				utils.LogErr("setup log file", err)
+				timer = time.NewTimer(time.Until(rl.timeToSwitchLog()))
+				rl.mu.Unlock()
+			case <-rl.stop:
+				timer.Stop()
+				return
+			}
+		}
+	}()
+	return nil
+}
+
+func (rl *SimpleLogger) Write(p []byte) (n int, err error) {
+	rl.mu.Lock()
+	defer rl.mu.Unlock()
+	if rl.file != nil {
+		return rl.file.Write(p)
+	}
+	return 0, nil
+}
+
+func (rl *SimpleLogger) Close() (err error) {
+	rl.mu.Lock()
+	defer rl.mu.Unlock()
+	err = rl.closeFile()
+	rl.stop <- struct{}{}
+	return nil
+}
+
+func (rl *SimpleLogger) setupFile() (err error) {
+	rl.closeFile()
+	filename := path.Join(
+		rl.Dir,
+		fmt.Sprintf("%s%s.log",
+			rl.LogName,
+			time.Now().Format("20060102.15:04:05.000"),
+		))
+	dir := path.Dir(filename)
+	if err := os.MkdirAll(dir, 0755); err != nil {
+		return err
+	}
+	rl.file, err = utils.OpenOrCreateFile(filename)
+	return
+}
+
+func (rl *SimpleLogger) closeFile() (err error) {
+	if rl.file != nil {
+		_ = rl.file.Sync()
+		err = rl.file.Close()
+	}
+	return
+}
+
+func (rl *SimpleLogger) timeToSwitchLog() time.Time {
+	return time.Now().Add(rl.Period).Truncate(rl.Period)
+}

internal/logger/simple_test.go

@@ -0,0 +1,63 @@
+package logger
+
+import (
+	"os"
+	"path"
+	"sort"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/require"
+	"github.com/yohamta/dagu/internal/utils"
+)
+
+func TestSimpleLogger(t *testing.T) {
+	tmpDir := utils.MustTempDir("test-simple-logger")
+	defer func() {
+		_ = os.RemoveAll(tmpDir)
+	}()
+
+	rl := NewSimpleLogger(tmpDir, "test", time.Millisecond*300)
+	rl.Open()
+
+	_, err := rl.Write([]byte("test log\n"))
+	require.NoError(t, err)
+
+	time.Sleep(time.Millisecond * 300)
+
+	_, err = rl.Write([]byte("test log2\n"))
+	require.NoError(t, err)
+
+	_ = rl.Close()
+	time.Sleep(time.Millisecond * 100)
+
+	f, err := os.Open(tmpDir)
+	require.NoError(t, err)
+	defer func() {
+		_ = f.Close()
+	}()
+
+	fis, _ := f.Readdir(0)
+	require.Equal(t, 2, len(fis))
+	for _, fi := range fis {
+		require.Regexp(t, "test\\d{8}.\\d{2}:\\d{2}:\\d{2}.\\d{3}.log", fi.Name())
+	}
+
+	sort.Slice(fis, func(i, j int) bool {
+		return fis[i].Name() < fis[j].Name()
+	})
+
+	b, _ := os.ReadFile(path.Join(tmpDir, fis[0].Name()))
+	require.Equal(t, "test log\n", string(b))
+
+	b, _ = os.ReadFile(path.Join(tmpDir, fis[1].Name()))
+	require.Equal(t, "test log2\n", string(b))
+}
+
+func TestTimeToSwitchLog(t *testing.T) {
+	rl := NewSimpleLogger("", "test", time.Hour*24)
+	tm := rl.timeToSwitchLog()
+	d := time.Hour*24 - time.Until(tm)
+	require.GreaterOrEqual(t, d, time.Duration(0))
+	require.LessOrEqual(t, time.Second, d)
+}

internal/runner/agent.go

@@ -16,8 +16,8 @@ import (
 
 type Agent struct {
 	*admin.Config
-	stop    chan struct{}
-	logFile *os.File
+	stop   chan struct{}
+	logger *logger.SimpleLogger
 }
 
 func NewAgent(cfg *admin.Config) *Agent {
@@ -44,8 +44,7 @@ func (a *Agent) Stop() {
 }
 
 func (a *Agent) start() error {
-	// TODO: log rotation
-	tl := &logger.TeeLogger{Writer: a.logFile}
+	tl := &logger.TeeLogger{Writer: a.logger}
 	if err := tl.Open(); err != nil {
 		return err
 	}
@@ -90,13 +89,16 @@ func (a *Agent) setupLogFile() (err error) {
 	if err := os.MkdirAll(dir, 0755); err != nil {
 		return err
 	}
-	a.logFile, err = utils.OpenOrCreateFile(filename)
+	a.logger = logger.NewSimpleLogger(
+		a.LogDir, "scheduler", time.Hour*24,
+	)
+	err = a.logger.Open()
 	return
 }
 
 func (a *Agent) closeLogFile() error {
-	if a.logFile != nil {
-		return a.logFile.Close()
+	if a.logger != nil {
+		return a.logger.Close()
 	}
 	return nil
 }