feat: implement logger

app/utils/logger/logger.go

@@ -0,0 +1,151 @@
+package logger
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"log/slog"
+	"os"
+	"strings"
+)
+
+var L *slog.Logger
+
+const (
+	reset  = "\033[0m"
+	red    = "\033[31m"
+	yellow = "\033[33m"
+	green  = "\033[32m"
+	blue   = "\033[36m"
+	gray   = "\033[90m"
+)
+
+type consoleHandler struct {
+	w        io.Writer
+	colorize bool
+}
+
+func (h *consoleHandler) Enabled(ctx context.Context, level slog.Level) bool {
+	return true
+}
+
+func (h *consoleHandler) Handle(ctx context.Context, r slog.Record) error {
+	level := r.Level.String()
+	color := reset
+
+	switch r.Level {
+	case slog.LevelError:
+		color = red
+	case slog.LevelWarn:
+		color = yellow
+	case slog.LevelInfo:
+		color = blue
+	case slog.LevelDebug:
+		color = gray
+	}
+
+	var msg string
+	if h.colorize {
+		msg = fmt.Sprintf("%s%s%s %s%s%s %s%s%s",
+			reset, r.Time.Format("15:04:05"), reset,
+			color, level, reset,
+			reset, r.Message, reset)
+	} else {
+		msg = fmt.Sprintf("%s %s %s", r.Time.Format("15:04:05"), level, r.Message)
+	}
+
+	var pairs []string
+	r.Attrs(func(attr slog.Attr) bool {
+		if h.colorize {
+			pairs = append(pairs, fmt.Sprintf("%s%s=%s%v%s", green, attr.Key, reset, attr.Value, reset))
+		} else {
+			pairs = append(pairs, fmt.Sprintf("%s=%v", attr.Key, attr.Value))
+		}
+		return true
+	})
+
+	if len(pairs) > 0 {
+		msg += " " + strings.Join(pairs, " ")
+	}
+
+	fmt.Fprintln(h.w, msg)
+	return nil
+}
+
+func (h *consoleHandler) WithAttrs(attrs []slog.Attr) slog.Handler {
+	return &consoleHandler{w: h.w, colorize: h.colorize}
+}
+
+func (h *consoleHandler) WithGroup(name string) slog.Handler {
+	return &consoleHandler{w: h.w, colorize: h.colorize}
+}
+
+func Init(service string, output io.Writer, level string, colorize bool) {
+	if output == nil {
+		output = os.Stderr
+	}
+
+	var lvl slog.Level
+	switch level {
+	case "debug":
+		lvl = slog.LevelDebug
+	case "warn":
+		lvl = slog.LevelWarn
+	case "error":
+		lvl = slog.LevelError
+	default:
+		lvl = slog.LevelInfo
+	}
+
+	if colorize {
+		L = slog.New(&consoleHandler{w: output, colorize: true}).With("service", service, "level", lvl.String())
+	} else {
+		L = slog.New(slog.NewJSONHandler(output, &slog.HandlerOptions{
+			Level:     lvl,
+			AddSource: false,
+			ReplaceAttr: func(groups []string, a slog.Attr) slog.Attr {
+				if a.Key == slog.TimeKey && groups == nil {
+					a.Key = "timestamp"
+				}
+				if a.Key == slog.LevelKey {
+					a.Key = "level"
+				}
+				if a.Key == slog.MessageKey {
+					a.Key = "message"
+				}
+				return a
+			},
+		})).With("service", service)
+	}
+}
+
+func Info(msg string, args ...any) {
+	if L != nil {
+		L.Info(msg, args...)
+	}
+}
+
+func Warn(msg string, args ...any) {
+	if L != nil {
+		L.Warn(msg, args...)
+	}
+}
+
+func Error(msg string, args ...any) {
+	if L != nil {
+		L.Error(msg, args...)
+	}
+}
+
+func Debug(msg string, args ...any) {
+	if L != nil {
+		L.Debug(msg, args...)
+	}
+}
+
+func With(args ...any) *slog.Logger {
+	if L == nil {
+		return nil
+	}
+	return L.With(args...)
+}