Function TestReadRotatedJSONLog

pkg/logging/json_logger_test.go:30–110

(t *testing.T)

)

func TestReadRotatedJSONLog(t *testing.T) {
	tmpDir := t.TempDir()
	if runtime.GOOS == "windows" {
		t.Skip("windows implementation does not seem to work right now and should be fixed: https://github.com/containerd/nerdctl/issues/3554")
	}
	file, err := os.CreateTemp(tmpDir, "logfile")
	if err != nil {
		t.Errorf("unable to create temp file, error: %s", err.Error())
	}
	stdoutBuf := &bytes.Buffer{}
	stderrBuf := &bytes.Buffer{}
	containerStopped := make(chan os.Signal)
	// Start to follow the container's log.
	fileName := file.Name()
	go func() {
		lvOpts := LogViewOptions{
			Follow:  true,
			LogPath: fileName,
		}
		viewLogsJSONFileDirect(lvOpts, file.Name(), stdoutBuf, stderrBuf, containerStopped)
	}()

	// log in stdout
	expectedStdout := "line0\nline1\nline2\nline3\nline4\nline5\nline6\nline7\nline8\nline9\n"
	dir := filepath.Dir(file.Name())
	baseName := filepath.Base(file.Name())

	// Write 10 lines to log file.
	// Let ReadLogs start.
	time.Sleep(50 * time.Millisecond)

	type logContent struct {
		Log    string `json:"log"`
		Stream string `json:"stream"`
		Time   string `json:"time"`
	}

	for line := 0; line < 10; line++ {
		// Write the first three lines to log file
		log := logContent{}
		log.Log = fmt.Sprintf("line%d\n", line)
		log.Stream = "stdout"
		log.Time = time.Now().Format(time.RFC3339Nano)
		time.Sleep(1 * time.Millisecond)
		logData, _ := json.Marshal(log)
		file.Write(logData)
		file.Write([]byte("\n"))

		if line == 5 {
			file.Close()
			// Pretend to rotate the log.
			rotatedName := fmt.Sprintf("%s.%s", baseName, time.Now().Format("20060102-150405"))
			rotatedName = filepath.Join(dir, rotatedName)
			if err := os.Rename(filepath.Join(dir, baseName), rotatedName); err != nil {
				t.Errorf("failed to rotate log %q to %q, error: %s", file.Name(), rotatedName, err.Error())
				return
			}