[service] Move logging to the core, remove pkg level logs

base/log/writer.go

@@ -0,0 +1,119 @@
+package log
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"sync"
+	"time"
+)
+
+// GlobalWriter is the global log writer.
+var GlobalWriter *LogWriter = nil
+
+type LogWriter struct {
+	writeLock sync.Mutex
+	isStdout  bool
+	file      *os.File
+}
+
+// NewStdoutWriter creates a new log writer thet will write to the stdout.
+func NewStdoutWriter() *LogWriter {
+	return &LogWriter{
+		file:     os.Stdout,
+		isStdout: true,
+	}
+}
+
+// NewFileWriter creates a new log writer that will write to a file. The file path will be <dir>/2006-01-02_15-04-05.log (with current date and time)
+func NewFileWriter(dir string) (*LogWriter, error) {
+	// Make sure log dir exists, if not, create with strict permission, as logs can contain sensitive data.
+	_ = os.MkdirAll(dir, 0o700)
+
+	// Open new log file.
+	logFile := time.Now().UTC().Format("2006-01-02_15-04-05") + ".log"
+	file, err := os.Create(filepath.Join(dir, logFile))
+	if err != nil {
+		return nil, err
+	}
+
+	return &LogWriter{
+		file:     file,
+		isStdout: false,
+	}, nil
+}
+
+// Write writes the buffer to the writer.
+func (l *LogWriter) Write(buf []byte) (int, error) {
+	if l == nil {
+		return 0, fmt.Errorf("log writer not initialized")
+	}
+
+	// No need to lock in stdout context.
+	if !l.isStdout {
+		l.writeLock.Lock()
+		defer l.writeLock.Unlock()
+	}
+
+	return l.file.Write(buf)
+}
+
+// WriteMessage writes the message to the writer.
+func (l *LogWriter) WriteMessage(msg Message, duplicates uint64) {
+	if l == nil {
+		return
+	}
+
+	// No need to lock in stdout context.
+	if !l.isStdout {
+		l.writeLock.Lock()
+		defer l.writeLock.Unlock()
+	}
+
+	fmt.Fprintln(l.file, formatLine(msg.(*logLine), duplicates, l.isStdout))
+}
+
+// IsStdout returns true if writer was initialized with stdout.
+func (l *LogWriter) IsStdout() bool {
+	return l != nil && l.isStdout
+}
+
+// Close closes the writer.
+func (l *LogWriter) Close() {
+	if l != nil && !l.isStdout {
+		_ = l.file.Close()
+	}
+}
+
+// CleanOldLogs deletes all log files in given directory that are older than the given threshold.
+func CleanOldLogs(dir string, threshold time.Duration) error {
+	// Get current log file name.
+	var currentLogFile string
+	if GlobalWriter != nil && GlobalWriter.file != nil {
+		currentLogFile = GlobalWriter.file.Name()
+	}
+
+	// Read dir entries.
+	files, err := os.ReadDir(dir)
+	if err != nil {
+		return fmt.Errorf("failed to read dir: %w", err)
+	}
+
+	// Remove files older than threshold
+	deleteOlderThan := time.Now().Add(-threshold)
+	for _, f := range files {
+		// Skip directories and the current log file.
+		if f.IsDir() || f.Name() == currentLogFile {
+			continue
+		}
+
+		// Delete log files.
+		if fileInfo, err := f.Info(); err == nil {
+			if fileInfo.ModTime().Before(deleteOlderThan) {
+				_ = os.Remove(filepath.Join(dir, f.Name()))
+			}
+		}
+	}
+
+	return nil
+}