Add better logging

internal/logger/logger.go

@@ -0,0 +1,59 @@
+package logger
+
+import (
+	"context"
+	"log/slog"
+	"os"
+)
+
+type contextKey string
+
+const requestIDKey contextKey = "request_id"
+
+// New creates a logger with the specified format (json or text) and level.
+func New(format string, level string) *slog.Logger {
+	var handler slog.Handler
+
+	logLevel := parseLevel(level)
+	opts := &slog.HandlerOptions{
+		Level:     logLevel,
+		AddSource: true, // Add file:line info for debugging
+	}
+
+	if format == "json" {
+		handler = slog.NewJSONHandler(os.Stdout, opts)
+	} else {
+		handler = slog.NewTextHandler(os.Stdout, opts)
+	}
+
+	return slog.New(handler)
+}
+
+// parseLevel converts a string level to slog.Level.
+func parseLevel(level string) slog.Level {
+	switch level {
+	case "debug":
+		return slog.LevelDebug
+	case "info":
+		return slog.LevelInfo
+	case "warn":
+		return slog.LevelWarn
+	case "error":
+		return slog.LevelError
+	default:
+		return slog.LevelInfo
+	}
+}
+
+// WithRequestID adds a request ID to the context for tracing.
+func WithRequestID(ctx context.Context, requestID string) context.Context {
+	return context.WithValue(ctx, requestIDKey, requestID)
+}
+
+// FromContext extracts the request ID from context, or returns empty string.
+func FromContext(ctx context.Context) string {
+	if id, ok := ctx.Value(requestIDKey).(string); ok {
+		return id
+	}
+	return ""
+}