feat: implement logging system

cmd/client/client.go

@@ -1,12 +1,12 @@
 package main
 
 import (
-	"log/slog"
+	"os"
 
-	"github.com/kyren223/eko/internal/utils"
+	"github.com/kyren223/eko/internal/utils/log"
 )
 
 func main() {
-	utils.SetupLogger("Client")
-	slog.Info("Eko 'Hello, World!'")
+	log.SetDefault(log.NewLogger("Client", os.Stdout, true))
+	log.Info("Eko 'Hello, World!'")
 }

cmd/server/server.go

@@ -1,15 +1,15 @@
 package main
 
 import (
-	"log/slog"
+	"os"
 
-	"github.com/kyren223/eko/internal/utils"
+	"github.com/kyren223/eko/internal/utils/log"
 )
 
 func main() {
-	utils.SetupLogger("Server")
-	slog.Debug("Eko 'Hello, World!'")
-	slog.Info("Eko 'Hello, World!'")
-	slog.Warn("Eko 'Hello, World!'")
-	slog.Error("Eko 'Hello, World!'")
+	log.SetDefault(log.NewLogger("Server", os.Stdout, true))
+	log.Debug("Eko 'Hello, World!'")
+	log.Info("Eko 'Hello, World!'")
+	log.Warn("Eko 'Hello, World!'")
+	log.Error("Eko 'Hello, World!'")
 }

internal/utils/log.go

@@ -1,44 +0,0 @@
-package utils
-
-import (
-	"context"
-	"fmt"
-	"io"
-	"log"
-	"log/slog"
-	"os"
-	"time"
-)
-
-func SetupLogger(name string) {
-	logger := slog.New(CustomHandler{os.Stdout, name, nil})
-	slog.SetDefault(logger)
-	slog.SetLogLoggerLevel()
-}
-
-type CustomHandler struct {
-	writer io.Writer
-	group   string
-	attrs  []slog.Attr
-}
-
-func (h CustomHandler) Handle(ctx context.Context, r slog.Record) error {
-	// timestamp := time.Now().Format(time.RFC3339Nano)
-	timestamp := time.Now().Format(time.TimeOnly)
-	severity := r.Level.String()
-	_, err := fmt.Fprintf(h.writer, "[%s] [%s/%s]: %s\n", timestamp, h.group, severity, r.Message)
-	return err
-}
-
-func (h CustomHandler) Enabled(ctx context.Context, level slog.Level) bool {
-	slog.Handler
-	return true
-}
-
-func (h CustomHandler) WithAttrs(attrs []slog.Attr) slog.Handler {
-	return &CustomHandler{h.writer, h.group, append(h.attrs, attrs...)}
-}
-
-func (h CustomHandler) WithGroup(name string) slog.Handler {
-	return &CustomHandler{h.writer, name, h.attrs}
-}

internal/utils/log/level.go

@@ -0,0 +1,25 @@
+package log
+
+type Level int
+
+func (l Level) String() string {
+	switch l {
+	case LevelDebug:
+		return "DEBUG"
+	case LevelInfo:
+		return "INFO"
+	case LevelWarn:
+		return "WARN"
+	case LevelError:
+		return "ERROR"
+	default:
+		return ""
+	}
+}
+
+const (
+	LevelDebug Level = -4
+	LevelInfo  Level = 0
+	LevelWarn  Level = 4
+	LevelError Level = 8
+)

internal/utils/log/log.go

@@ -0,0 +1,26 @@
+package log
+
+var (
+	level  Level
+	logger *Logger
+)
+
+func SetDefault(l *Logger) {
+	logger = l
+}
+
+func Debug(message string, a ...any) error {
+	return logger.Log(LevelDebug, message, a)
+}
+
+func Info(message string, a ...any) error {
+	return logger.Log(LevelInfo, message, a)
+}
+
+func Warn(message string, a ...any) error {
+	return logger.Log(LevelWarn, message, a)
+}
+
+func Error(message string, a ...any) error {
+	return logger.Log(LevelError, message, a)
+}

internal/utils/log/logger.go

@@ -0,0 +1,55 @@
+package log
+
+import (
+	"fmt"
+	"go/format"
+	"io"
+	"os"
+	"sync"
+	"time"
+)
+
+type Logger struct {
+	name   string
+	Level
+	writer io.Writer
+	mu sync.Mutex
+	color bool
+}
+
+func NewLogger(name string, writer io.Writer, ansi bool) *Logger {
+	color := ansi && (writer == os.Stdout || writer == os.Stderr)
+	return &Logger{name, LevelInfo, writer, sync.Mutex{}, color}
+}
+
+func (l *Logger) Log(level Level, message string, a ...any) error {
+	if l.Level > level {
+		return nil
+	}
+
+	timestamp := time.Now().Format(time.TimeOnly)
+	severity := level.String()
+
+	// TODO: add support for ANSI coloring
+	l.mu.Lock()
+	_, err := fmt.Fprintf(l.writer, "[%s] [%s/%s]: %s\n", timestamp, l.name, severity, message, a)
+	l.mu.Unlock()
+	return err
+}
+
+func (l *Logger) Debug(message string, a ...any) error {
+	return l.Log(LevelDebug, message, a)
+}
+
+func (l *Logger) Info(message string, a ...any) error {
+	return l.Log(LevelInfo, message, a)
+}
+
+func (l *Logger) Warn(message string, a ...any) error {
+	return l.Log(LevelWarn, message, a)
+}
+
+func (l *Logger) Error(message string, a ...any) error {
+	return l.Log(LevelError, message, a)
+}
+