From 20cee1421fc6aa9798dbb783a65de29ff63bede4 Mon Sep 17 00:00:00 2001
From: Edward <crazybber@outlook.com>
Date: Mon, 27 Apr 2020 23:36:22 +0800
Subject: [PATCH] add concurrency and syncs

---
 README.md                         |   4 +-
 concurrency/rate_limiting_test.go | 105 ++++++++++++++++++++++++++++++
 syncs/README.md                   |   3 +
 3 files changed, 109 insertions(+), 3 deletions(-)
 create mode 100644 concurrency/rate_limiting_test.go
 create mode 100644 syncs/README.md

diff --git a/README.md b/README.md
index a0ac899..e3e4b99 100644
--- a/README.md
+++ b/README.md
@@ -44,9 +44,7 @@ Go常用的、面向工程化和最佳实践的模式套路，包含常见的23
 + [访问者模式(Visitor)](./behavior/23_visitor)
 + [闭包选项模式(Function Option)](./behavior/26_option)
 
-## 参考资(Design patters Articles)
-
-[大话设计模式](https://book.douban.com/subject/2334288/)
+## 参考资料(Design patters Articles)
 
 [GO模式文档](https://github.com/nynicg/go-patterns)
 
diff --git a/concurrency/rate_limiting_test.go b/concurrency/rate_limiting_test.go
new file mode 100644
index 0000000..f58131a
--- /dev/null
+++ b/concurrency/rate_limiting_test.go
@@ -0,0 +1,105 @@
+package concurrency
+
+import (
+	"fmt"
+	"testing"
+	"time"
+)
+
+/*
+
+Rate limiting is an very important mechanism
+With limiting you can controll resource utilization and maintain quality of service.
+Go  supports rate limiting by using goroutines, channels, and tickers.
+*/
+
+func TestRateLimiting(t *testing.T) {
+	requests := make(chan int, 5)
+	for i := 1; i <= 5; i++ {
+		requests <- i
+	}
+	close(requests)
+
+	limiter := time.Tick(200 * time.Millisecond)
+
+	for req := range requests {
+		<-limiter
+		t.Log("Sev request by 2000 Millisecond", req, time.Now())
+	}
+
+	burstyLimiter := make(chan struct{}, 3)
+
+	//init burstyLimiter
+	for i := 0; i < 3; i++ {
+		burstyLimiter <- struct{}{}
+	}
+	go func() {
+		for {
+			select {
+			case <-time.Tick(200 * time.Millisecond):
+				burstyLimiter <- struct{}{}
+			}
+
+		}
+	}()
+
+	//max request queue
+	burstyRequestsQueue := make(chan int, 5)
+	for i := 1; i <= 5; i++ {
+		burstyRequestsQueue <- i
+	}
+	close(burstyRequestsQueue)
+
+	for req := range burstyRequestsQueue {
+		<-burstyLimiter
+		if len(burstyLimiter) > 0 {
+			fmt.Println("working current in bursting status!")
+		} else {
+			fmt.Println("working current in normal status!")
+		}
+		fmt.Println("request handled", req, time.Now())
+	}
+
+	rateLimiting()
+
+}
+
+func rateLimiting() {
+
+	requests := make(chan int, 5)
+	for i := 1; i <= 5; i++ {
+		requests <- i
+	}
+	close(requests)
+
+	limiter := time.Tick(200 * time.Millisecond)
+
+	for req := range requests {
+		<-limiter
+		fmt.Println("request", req, time.Now())
+	}
+
+	//突发限流器
+	burstyLimiter := make(chan time.Time, 3)
+
+	for i := 0; i < 3; i++ {
+		burstyLimiter <- time.Now()
+	}
+
+	go func() {
+		for t := range time.Tick(200 * time.Millisecond) {
+			burstyLimiter <- t
+		}
+	}()
+
+	//请求队列
+	burstyRequests := make(chan int, 5)
+	for i := 1; i <= 5; i++ {
+		burstyRequests <- i
+	}
+	close(burstyRequests)
+	for req := range burstyRequests {
+		<-burstyLimiter
+		fmt.Println("request", req, time.Now())
+	}
+}
diff --git a/syncs/README.md b/syncs/README.md
new file mode 100644
index 0000000..ff76b98
--- /dev/null
+++ b/syncs/README.md
@@ -0,0 +1,3 @@
+# 同步模式
+
+s同步处理中的一些常用模式 
\ No newline at end of file