add

trading_assistant_api/common/logger/logger.go

@@ -3,6 +3,7 @@ package logger
 import (
 	"log"
 	"os"
+	"fmt"
 )
 
 type Logger interface {
@@ -30,3 +31,18 @@ func SetLogger(l Logger) {
 		defaultLogger = l
 	}
 }
+
+type prefLogger struct {
+	prefix string
+}
+
+func (p *prefLogger) Printf(format string, v ...any) {
+	defaultLogger.Printf("%s %s", p.prefix, fmt.Sprintf(format, v...))
+}
+func (p *prefLogger) Fatalf(format string, v ...any) {
+	defaultLogger.Fatalf("%s %s", p.prefix, fmt.Sprintf(format, v...))
+}
+
+func WithPrefix(prefix string) Logger {
+	return &prefLogger{prefix: prefix}
+}