docs: 手动实现 simple log 日志库

写入指定日志文件

simplelog/simplelog.go

@@ -37,6 +37,7 @@ var (
 
 // Logger 日志类
 type Logger struct {
+	fn           string
 	w            io.Writer
 	timeFormat   string
 	loggerFormat string
@@ -101,15 +102,18 @@ type Option struct {
 	TimeFormat string
 	LogFormat  string
 	LevelFlag  LevelFlag
+	LogFile    string
 }
 
 type OptionFunc func(*Option)
 
 func WithWriter(writer io.Writer) OptionFunc {
 	return func(option *Option) {
+		if len(option.LogFile) == 0 {
 			option.Writer = writer
 		}
 	}
+}
 
 func WithTimeFormat(timeFormat string) OptionFunc {
 	return func(option *Option) {
@@ -129,12 +133,26 @@ func WithLogFlag(flag LevelFlag) OptionFunc {
 	}
 }
 
+func WithLogFile(filePath string) OptionFunc {
+	return func(option *Option) {
+		if len(filePath) > 0 {
+			option.LogFile = filePath
+			file, err := os.OpenFile(filePath, os.O_APPEND|os.O_CREATE|os.O_WRONLY, 0644)
+			if err != nil {
+				panic(err)
+			}
+			option.Writer = file
+		}
+	}
+}
+
 // 默认参数
 var defaultOption = &Option{
 	Writer:     os.Stdout,
 	TimeFormat: "2006-01-02 15:04:05.99",
 	LogFormat:  "%-22s %s %v --- [%20s] : %s\n",
 	LevelFlag:  FlagInfo | FlagWarn | FlagError | FlagDebug,
+	LogFile:    "",
 }
 
 // NewOption 构造 Option 参数
@@ -155,5 +173,6 @@ func NewLog(opts ...OptionFunc) *Logger {
 		timeFormat:   opt.TimeFormat,
 		loggerFormat: opt.LogFormat,
 		flag:         opt.LevelFlag,
+		fn:           opt.LogFile,
 	}
 }

simplelog/simplelog_test.go

@@ -49,7 +49,7 @@ func TestLogToFile(t *testing.T) {
 
 	fmt.Printf("写入日志文件 %s\n", logFilePath)
 	log := NewLog(
-		WithWriter(f),
+		WithLogFile(logFilePath),
 		WithLogFlag(FlagInfo|FlagDebug|FlagWarn),
 	)