From 39fb8208fc479eeb14ec849cf3b8d69a0dfbbb1a Mon Sep 17 00:00:00 2001
From: FishGoddess <1149062639@qq.com>
Date: Mon, 9 Mar 2020 17:23:21 +0800
Subject: [PATCH 1/3] =?UTF-8?q?=E5=A2=9E=E5=8A=A0=20Logger=20=E6=96=B0?=
 =?UTF-8?q?=E7=9A=84=E5=8A=9F=E8=83=BD=E7=89=B9=E6=80=A7?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 FUTURE.md         |  9 ++++--
 README.md         |  2 +-
 logger.go         | 52 ++++++++++++++++++++++++++++++----
 logger_handler.go |  2 +-
 logger_test.go    | 72 +++++++++++++++++++++++++++++++++++++++++++++--
 5 files changed, 125 insertions(+), 12 deletions(-)

diff --git a/FUTURE.md b/FUTURE.md
index a4e9e91..703b0a1 100644
--- a/FUTURE.md
+++ b/FUTURE.md
@@ -1,11 +1,16 @@
 ## ✒ 未来版本的新特性 (Features in future version)
 
-### v0.0.11
+### v0.0.12
 * 时间格式化操作中 time.Time.AppendFormat 消耗性能很多，思考优化方案
 
-### v0.0.10
+### v0.0.11
 * 支持日志输出为 Json 形式，通过增加 JSON 日志处理器实现
 
+### v0.0.10
+* 扩展了 Logger 的方法，可以获取到内部的属性，为日志处理器做准备
+* 支持创建 Logger 对象之后修改它的输出源 writer（这是个之前被遗漏的功能特性哈哈）
+* 调整了内部 log 方法的锁机制，使用类似于写时复制的方式释放日志输出的并发性
+
 ### v0.0.9
 * 支持日志输出函数，日志信息可以是一个返回 string 的函数
 * 公开 PrefixOf 方法，方便用户自定义处理器的时候获取日志级别字符串
diff --git a/README.md b/README.md
index bba335a..c92ae3d 100644
--- a/README.md
+++ b/README.md
@@ -126,7 +126,7 @@ $ go test -v ./_examples/benchmarks_test.go -bench=. -benchtime=1s
 **行为，主要体现在对参数 v interface{} 进行类型检测的逻辑上，而日志输出都是字符串，这一个**
 **判断是可以省略的，可以减少很多运行时操作时间！v0.0.8 版本开始使用了更有效率的输出方式！**
 
-**3. 经过对 v0.0.8 版本的性能检测，发现时间格式化操作消耗了接近一般的处理时间，**
+**3. 经过对 v0.0.8 版本的性能检测，发现时间格式化操作消耗了接近一半的处理时间，**
 **主要体现在 time.Time.AppendFormat 的调用上。目前正在思考优化方案，或许会在之后的版本中解决！**
 
 ### 👥 贡献者
diff --git a/logger.go b/logger.go
index 14472d7..922bb69 100644
--- a/logger.go
+++ b/logger.go
@@ -117,6 +117,13 @@ func (l *Logger) ChangeLevelTo(newLevel LoggerLevel) {
     l.level = newLevel
 }
 
+// Level returns the logger level of l.
+func (l *Logger) Level() LoggerLevel {
+    l.mu.RLock()
+    defer l.mu.RUnlock()
+    return l.level
+}
+
 // EnableFileInfo means every log will contain file info like line number.
 // However, you should know that this is expensive in time.
 // So be sure you really need it or keep it disabled.
@@ -155,12 +162,24 @@ func (l *Logger) SetHandlers(handlers ...LoggerHandler) bool {
         return false
     }
 
+    // 先清空原本的日志处理器，再添加新的日志处理器
     l.mu.Lock()
     defer l.mu.Unlock()
-    l.handlers = handlers
+    l.handlers = nil
+    l.handlers = append(l.handlers, handlers...)
     return true
 }
 
+// Handlers returns all handlers of l in a copy slice.
+func (l *Logger) Handlers() []LoggerHandler {
+    l.mu.RLock()
+    defer l.mu.RUnlock()
+
+    // 返回的是日志处理器的副本，防止被非法篡改
+    handlers := make([]LoggerHandler, 0, len(l.handlers))
+    return append(handlers, l.handlers...)
+}
+
 // SetFormatOfTime sets format of time as you want.
 // Default is "2006-01-02 15:04:05", see DefaultFormatOfTime.
 func (l *Logger) SetFormatOfTime(formatOfTime string) {
@@ -169,8 +188,24 @@ func (l *Logger) SetFormatOfTime(formatOfTime string) {
     l.formatOfTime = formatOfTime
 }
 
+// FormatOfTime returns the format of time in l.
+func (l *Logger) FormatOfTime() string {
+    l.mu.RLock()
+    defer l.mu.RUnlock()
+    return l.formatOfTime
+}
+
+// ChangeWriterTo changes current writer to newWriter.
+func (l *Logger) ChangeWriterTo(newWriter io.Writer) {
+    l.mu.Lock()
+    defer l.mu.Unlock()
+    l.writer = newWriter
+}
+
 // Writer returns the writer of l.
 func (l *Logger) Writer() io.Writer {
+    l.mu.RLock()
+    defer l.mu.RUnlock()
     return l.writer
 }
 
@@ -183,21 +218,26 @@ func (l *Logger) log(callDepth int, level LoggerLevel, msg string) {
 
     // 加上读锁
     l.mu.RLock()
-    defer l.mu.RUnlock()
 
     // 以下两种条件直接返回，不记录日志：
     // 1. 日志处于禁用状态，也就是 l.running = false
     // 2. 日志记录器的日志级别高于这条记录的日志级别
     if !l.running || l.level > level {
+        l.mu.RUnlock()
         return
     }
 
+    // 提前释放读锁，后续操作非常消耗时间，可以不用加锁了，彻底释放并发的天性
+    // 但是 needFileInfo 的获取需要保证并发安全，就在释放锁之前拷贝一份副本，
+    // 即使释放锁之后有人修改了这个属性，也和这里无关了，因为在执行这个 log 方法的时间点上
+    // 这个属性的值就已经确定了，并且不允许被修改了，这类似于 copy on write 的解决思路。
+    // 这个解决并发竞争的方案是否没有问题，需要时间的验证才知道
+    needFileInfo := l.needFileInfo
+    l.mu.RUnlock()
+
     // 如果需要文件信息，对当前的 msg 进行包装
-    if l.needFileInfo {
-        // 提前释放读锁，后续操作非常消耗时间，等获取完文件信息再上读锁
-        l.mu.RUnlock()
+    if needFileInfo {
         msg = wrapMessageWithFileInfo(callDepth, msg)
-        l.mu.RLock()
     }
 
     // 处理日志
diff --git a/logger_handler.go b/logger_handler.go
index 1195cd3..2b0431f 100644
--- a/logger_handler.go
+++ b/logger_handler.go
@@ -39,6 +39,6 @@ func (lh LoggerHandler) handle(logger *Logger, level LoggerLevel, now time.Time,
 // The log handled by this handler will be like "[Info] [2020-03-06 16:10:44] msg".
 // If you want to customize, just code your own handler, then replace it!
 func DefaultLoggerHandler(logger *Logger, level LoggerLevel, now time.Time, msg string) bool {
-    logger.Writer().Write([]byte("[" + PrefixOf(level) + "] [" + now.Format(logger.formatOfTime) + "] " + msg + "\n"))
+    logger.Writer().Write([]byte("[" + PrefixOf(level) + "] [" + now.Format(logger.FormatOfTime()) + "] " + msg + "\n"))
     return true
 }
diff --git a/logger_test.go b/logger_test.go
index 7d97fe1..3c9a8cb 100644
--- a/logger_test.go
+++ b/logger_test.go
@@ -21,6 +21,9 @@ package logit
 import (
     "fmt"
     "os"
+    "strconv"
+    "strings"
+    "sync"
     "testing"
     "time"
 )
@@ -62,6 +65,7 @@ func TestLoggerEnable(t *testing.T) {
 // 测试日志记录器的级别控制是否可用
 func TestLoggerLevel(t *testing.T) {
     logger := NewLogger(os.Stdout, WarnLevel)
+    logger.Warn(logger.Level().String())
     logger.Info("这条 info 级别的内容可以显示吗？")
     logger.Error("这条 error 级别的内容可以显示吗？")
     logger.Warn("这条 warn 级别的内容可以显示吗？")
@@ -131,7 +135,71 @@ func TestLoggerAddHandlersAndSetHandlers(t *testing.T) {
 // 测试更改时间格式化标准的方法
 func TestLoggerSetFormatOfTime(t *testing.T) {
     logger := NewLogger(os.Stdout, InfoLevel)
-    logger.Info("当前时间格式化信息！")
+    logger.Info("当前时间格式化信息！" + logger.FormatOfTime())
     logger.SetFormatOfTime("2006年01月02日 15点04分05秒")
-    logger.Info("更改之后的时间格式化信息！")
+    logger.Info("更改之后的时间格式化信息！" + logger.FormatOfTime())
+}
+
+// 测试获取日志处理器的方法
+func TestLoggerHandlers(t *testing.T) {
+    logger := NewStdoutLogger(InfoLevel)
+    handlers := logger.Handlers()
+
+    // 需要判断地址是否一样，一样说明有问题
+    if &handlers[0] == &logger.handlers[0] {
+        t.Fatal("handlers 获取的数据和底层数据地址一样！这是有问题的！")
+    }
+
+    // 显示每个日志处理器的地址
+    logger.Info("handlers 个数：" + strconv.Itoa(len(handlers)))
+    logger.InfoFunction(func() string {
+        builder := strings.Builder{}
+        for _, handler := range handlers {
+            builder.WriteString(fmt.Sprintf("%p ", &handler))
+        }
+        return builder.String()
+    })
+
+    // 尝试非法篡改日志处理器
+    handlers[0] = func(logger *Logger, level LoggerLevel, now time.Time, msg string) bool {
+        fmt.Println("哈哈哈被非法篡改了！！！")
+        return false
+    }
+    logger.Warn("这条信息需要显示出来！")
+}
+
+// 测试更改写出器的方法
+func TestLoggerChangeWriterTo(t *testing.T) {
+    logger := NewStdoutLogger(DebugLevel)
+    fmt.Println(logger.writer)
+    logger.Debug("哈哈哈")
+
+    file, _ := os.Create("Z:/TestLoggerChangeWriterTo.log")
+    logger.ChangeWriterTo(file)
+    fmt.Println(logger.writer)
+    logger.Debug("哈哈哈文件？")
+}
+
+// 测试并发情况下使用 Logger
+func TestLoggerInConcurrency(t *testing.T) {
+
+    logger := NewFileLogger("Z:/TestLoggerInConcurrency.log", DebugLevel)
+    //logger := NewStdoutLogger(DebugLevel)
+
+    group := sync.WaitGroup{}
+    for i := 0; i < 100; i++ {
+        group.Add(1)
+        go func(num int) {
+            if num == 30 || num == 60 {
+                logger.ChangeLevelTo(InfoLevel)
+            }
+            logger.Info(strconv.Itoa(num))
+            if num == 60 || num == 90 {
+                logger.ChangeWriterTo(os.Stdout)
+            }
+            group.Done()
+        }(i)
+    }
+
+    group.Wait()
 }

From ee34d279717060fc9bdb8c51f9e358af72a589dc Mon Sep 17 00:00:00 2001
From: FishGoddess <1149062639@qq.com>
Date: Mon, 9 Mar 2020 21:54:16 +0800
Subject: [PATCH 2/3] =?UTF-8?q?v0.0.10=20=E5=BE=AE=E7=89=B9=E6=80=A7?=
 =?UTF-8?q?=E5=AE=8C=E5=96=84=E7=89=88=E6=9C=AC=E9=A2=84=E5=8F=91=E5=B8=83?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 _examples/logger.go | 7 +++++--
 doc.go              | 7 +++++--
 logit.go            | 7 +++++++
 3 files changed, 17 insertions(+), 4 deletions(-)

diff --git a/_examples/logger.go b/_examples/logger.go
index c961006..d8738da 100644
--- a/_examples/logger.go
+++ b/_examples/logger.go
@@ -34,9 +34,9 @@ func main() {
 
     // Then you will be easy to log!
     logger.Debug("this is a debug message!")
-    logger.Info("this is a info message!")
+    logger.Info("this is an info message!")
     logger.Warn("this is a warn message!")
-    logger.Error("this is a error message!")
+    logger.Error("this is an error message!")
 
     // NewLogger creates a new Logger holder.
     // The first parameter "os.Stdout" is a writer for logging.
@@ -60,4 +60,7 @@ func main() {
         r := rand.New(rand.NewSource(time.Now().Unix()))
         return "debug rand int: " + strconv.Itoa(r.Intn(100))
     })
+
+    // If you want to change logger's writer, try this:
+    logger.ChangeWriterTo(os.Stdout)
 }
diff --git a/doc.go b/doc.go
index a19e03f..2de92c1 100644
--- a/doc.go
+++ b/doc.go
@@ -42,9 +42,9 @@ Package logit provides an easy way to use foundation for your logging operations
 
     // Then you will be easy to log!
     logger.Debug("this is a debug message!")
-    logger.Info("this is a info message!")
+    logger.Info("this is an info message!")
     logger.Warn("this is a warn message!")
-    logger.Error("this is a error message!")
+    logger.Error("this is an error message!")
 
     // NewLogger creates a new Logger holder.
     // The first parameter "os.Stdout" is a writer for logging.
@@ -69,6 +69,9 @@ Package logit provides an easy way to use foundation for your logging operations
         return "debug rand int: " + strconv.Itoa(r.Intn(100))
     })
 
+    // If you want to change logger's writer, try this:
+    logger.ChangeWriterTo(os.Stdout)
+
 3. enable or disable:
 
     // Every new Logger is running.
diff --git a/logit.go b/logit.go
index a767db8..71f9d06 100644
--- a/logit.go
+++ b/logit.go
@@ -18,6 +18,8 @@
 
 package logit
 
+import "io"
+
 // defaultLogger is a Logger holder for global usage.
 // Default level is info level.
 var defaultLogger = NewStdoutLogger(InfoLevel)
@@ -122,3 +124,8 @@ func WarnFunction(msgGenerator func() string) {
 func ErrorFunction(messageGenerator func() string) {
     defaultLogger.ErrorFunction(messageGenerator)
 }
+
+// ChangeWriterTo changes current writer to newWriter.
+func ChangeWriterTo(newWriter io.Writer) {
+    defaultLogger.ChangeWriterTo(newWriter)
+}

From 4ad01da1769ca6355195a3cc11a48f9a2a1c4766 Mon Sep 17 00:00:00 2001
From: FishGoddess <1149062639@qq.com>
Date: Tue, 10 Mar 2020 13:37:07 +0800
Subject: [PATCH 3/3] =?UTF-8?q?v0.0.10=20=E7=89=88=E6=9C=AC=E5=8F=91?=
 =?UTF-8?q?=E5=B8=83?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 HISTORY.md   | 6 ++++++
 README.en.md | 2 +-
 README.md    | 2 +-
 doc.go       | 2 +-
 4 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/HISTORY.md b/HISTORY.md
index 2a014ab..1aa20ad 100644
--- a/HISTORY.md
+++ b/HISTORY.md
@@ -1,5 +1,11 @@
 ## ✒ 历史版本的特性介绍 (Features in old version)
 
+### v0.0.10
+> 此版本发布于 2020-03-10
+* 扩展了 Logger 的方法，可以获取到内部的属性，为日志处理器做准备
+* 支持创建 Logger 对象之后修改它的输出源 writer（这是个之前被遗漏的功能特性哈哈）
+* 调整了内部 log 方法的锁机制，使用类似于写时复制的方式释放日志输出的并发性
+
 ### v0.0.9
 > 此版本发布于 2020-03-09
 * 支持日志输出函数，日志信息可以是一个返回 string 的函数
diff --git a/README.en.md b/README.en.md
index c3f85da..72e8149 100644
--- a/README.en.md
+++ b/README.en.md
@@ -39,7 +39,7 @@ module your_project_name
 go 1.14
 
 require (
-    github.com/FishGoddess/logit v0.0.9
+    github.com/FishGoddess/logit v0.0.10
 )
 ```
 
diff --git a/README.md b/README.md
index c92ae3d..81b0552 100644
--- a/README.md
+++ b/README.md
@@ -39,7 +39,7 @@ module your_project_name
 go 1.14
 
 require (
-    github.com/FishGoddess/logit v0.0.9
+    github.com/FishGoddess/logit v0.0.10
 )
 ```
 
diff --git a/doc.go b/doc.go
index 2de92c1..dbe83ce 100644
--- a/doc.go
+++ b/doc.go
@@ -170,4 +170,4 @@ Package logit provides an easy way to use foundation for your logging operations
 package logit // import "github.com/FishGoddess/logit"
 
 // Version is the version string representation of the "logit" package.
-const Version = "0.0.9"
+const Version = "0.0.10"