update

ReadMe_CN.md

@@ -0,0 +1,27 @@
+## groupcache快速入门
+
+### 功能介绍
+groupcache是go语言开发的缓存库。用于替换memcache的。
+#### 代码框架
+![](./1.png)
+
+### 使用入门
+```shell
+cd example
+go build
+./main 127.0.0.1:8001 127.0.0.1:8002 127.0.0.1:8003
+```
+
+### 分析目的
++ consistenthash(提供一致性哈希算法的支持)，
++ lru(提供了LRU方式清楚缓存的算法)，
++ singleflight(保证了多次相同请求只去获取值一次，减少了资源消耗)，
+https://segmentfault.com/a/1190000018464029
+
+### 参考资料
++ [《groupcache 使用入门》](http:https://betazk.github.io/2014/12/groupcache%E5%A6%82%E4%BD%95%E4%BD%BF%E7%94%A8%E7%9A%84%E4%B8%80%E4%B8%AA%E7%AE%80%E5%8D%95%E4%BE%8B%E5%AD%90/)
++ [Playing with groupcache](https://capotej.com/blog/2013/07/28/playing-with-groupcache/)
+
+
+https://www.jianshu.com/p/5c3db568b8b8
+https://juejin.im/entry/57c3ce697db2a200680ab024

example/go.mod

@@ -0,0 +1,7 @@
+module main
+
+go 1.14
+
+require github.com/golang/groupcache v0.0.0
+
+replace github.com/golang/groupcache v0.0.0 => ../

example/go.sum

@@ -0,0 +1,19 @@
+github.com/golang/groupcache v0.0.0-20200121045136-8c9f03a8e57e/go.mod h1:cIg4eruTrX1D+g88fzRXU5OdNfaM+9IcxsU14FzY7Hc=
+github.com/golang/protobuf v1.4.0-rc.1/go.mod h1:ceaxUfeHdC40wWswd/P6IGgMaK3YpKi5j83Wpe3EHw8=
+github.com/golang/protobuf v1.4.0-rc.1.0.20200221234624-67d41d38c208/go.mod h1:xKAWHe0F5eneWXFV3EuXVDTCmh+JuBKY0li0aMyXATA=
+github.com/golang/protobuf v1.4.0-rc.2/go.mod h1:LlEzMj4AhA7rCAGe4KMBDvJI+AwstrUpVNzEA03Pprs=
+github.com/golang/protobuf v1.4.0-rc.4.0.20200313231945-b860323f09d0/go.mod h1:WU3c8KckQ9AFe+yFwt9sWVRKCVIyN9cPHBJSNnbL67w=
+github.com/golang/protobuf v1.4.0/go.mod h1:jodUvKwWbYaEsadDk5Fwe5c77LiNKVO9IDvqG2KuDX0=
+github.com/golang/protobuf v1.4.2 h1:+Z5KGCizgyZCbGh1KZqA0fcLLkwbsjIzS4aV2v7wJX0=
+github.com/golang/protobuf v1.4.2/go.mod h1:oDoupMAO8OvCJWAcko0GGGIgR6R6ocIYbsSw735rRwI=
+github.com/google/go-cmp v0.3.0/go.mod h1:8QqcDgzrUqlUb/G2PQTWiueGozuR1884gddMywk6iLU=
+github.com/google/go-cmp v0.3.1/go.mod h1:8QqcDgzrUqlUb/G2PQTWiueGozuR1884gddMywk6iLU=
+github.com/google/go-cmp v0.4.0/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
+golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
+google.golang.org/protobuf v0.0.0-20200109180630-ec00e32a8dfd/go.mod h1:DFci5gLYBciE7Vtevhsrf46CRTquxDuWsQurQQe4oz8=
+google.golang.org/protobuf v0.0.0-20200221191635-4d8936d0db64/go.mod h1:kwYJMbMJ01Woi6D6+Kah6886xMZcty6N08ah7+eCXa0=
+google.golang.org/protobuf v0.0.0-20200228230310-ab0ca4ff8a60/go.mod h1:cfTl7dwQJ+fmap5saPgwCLgHXTUD7jkjRqWcaiX5VyM=
+google.golang.org/protobuf v1.20.1-0.20200309200217-e05f789c0967/go.mod h1:A+miEFZTKqfCUM6K7xSMQL9OKL/b6hQv+e19PK+JZNE=
+google.golang.org/protobuf v1.21.0/go.mod h1:47Nbq4nVaFHyn7ilMalzfO3qCViNmqZ2kzikPIcrTAo=
+google.golang.org/protobuf v1.23.0 h1:4MY060fB1DLGMB/7MBTLnwQUY6+F09GEiz6SsrNqyzM=
+google.golang.org/protobuf v1.23.0/go.mod h1:EGpADcykh3NcUnDUJcl1+ZksZNG86OlYog2l/sGQquU=

example/main.go

@@ -0,0 +1,77 @@
+package main
+
+import (
+ "context"
+ "flag"
+ "fmt"
+ "io/ioutil"
+ "log"
+ "net/http"
+ "os"
+ "strconv"
+ "strings"
+
+ "github.com/golang/groupcache"
+)
+
+var (
+ peers_addrs = []string{"127.0.0.1:8001", "127.0.0.1:8002", "127.0.0.1:8003"}
+ rpc_addrs = []string{"127.0.0.1:9001", "127.0.0.1:9002", "127.0.0.1:9003"}
+ index = flag.Int("index", 0, "peer index")
+)
+
+func main() {
+ flag.Parse()
+ peers_addrs := make([]string, 3)
+ rpc_addrs := make([]string, 3)
+ if len(os.Args) > 0 {
+ for i := 1; i < 4; i++ {
+ peers_addrs[i-1] = os.Args[i]
+ rpcaddr := strings.Split(os.Args[i], ":")[1]
+ port, _ := strconv.Atoi(rpcaddr)
+ rpc_addrs[i-1] = ":" + strconv.Itoa(port+1000)
+ }
+ }
+ if *index < 0 || *index >= len(peers_addrs) {
+ fmt.Printf("peer_index %d not invalid\n", *index)
+ os.Exit(1)
+ }
+ peers := groupcache.NewHTTPPool(addrToURL(peers_addrs[*index]))
+ var stringcache = groupcache.NewGroup("SlowDBCache", 64<<20, groupcache.GetterFunc(
+ func(ctx context.Context, key string, dest groupcache.Sink) error {
+ result, err := ioutil.ReadFile(key)
+ if err != nil {
+ log.Fatal(err)
+ return err
+ }
+ fmt.Printf("asking for %s from dbserver\n", key)
+ dest.SetBytes([]byte(result))
+ return nil
+ }))
+
+ peers.Set(addrsToURLs(peers_addrs)...)
+
+ http.HandleFunc("/zk", func(rw http.ResponseWriter, r *http.Request) {
+ log.Println(r.URL.Query().Get("key"))
+ var data []byte
+ k := r.URL.Query().Get("key")
+ fmt.Printf("cli asked for %s from groupcache\n", k)
+ stringcache.Get(nil, k, groupcache.AllocatingByteSliceSink(&data))
+ rw.Write([]byte(data))
+ })
+ go http.ListenAndServe(rpc_addrs[*index], nil)
+ rpcaddr := strings.Split(os.Args[1], ":")[1]
+ log.Fatal(http.ListenAndServe(":"+rpcaddr, peers))
+}
+
+func addrToURL(addr string) string {
+ return "http:https://" + addr
+}
+
+func addrsToURLs(addrs []string) []string {
+ result := make([]string, 0)
+ for _, addr := range addrs {
+ result = append(result, addrToURL(addr))
+ }
+ return result
+}

go.mod

@@ -0,0 +1,8 @@
+module groupcache
+
+go 1.14
+
+require (
+ github.com/golang/groupcache v0.0.0-20200121045136-8c9f03a8e57e
+ github.com/golang/protobuf v1.4.2
+)

go.sum

@@ -0,0 +1,20 @@
+github.com/golang/groupcache v0.0.0-20200121045136-8c9f03a8e57e h1:1r7pUrabqp18hOBcwBwiTsbnFeTZHV9eER/QT5JVZxY=
+github.com/golang/groupcache v0.0.0-20200121045136-8c9f03a8e57e/go.mod h1:cIg4eruTrX1D+g88fzRXU5OdNfaM+9IcxsU14FzY7Hc=
+github.com/golang/protobuf v1.4.0-rc.1/go.mod h1:ceaxUfeHdC40wWswd/P6IGgMaK3YpKi5j83Wpe3EHw8=
+github.com/golang/protobuf v1.4.0-rc.1.0.20200221234624-67d41d38c208/go.mod h1:xKAWHe0F5eneWXFV3EuXVDTCmh+JuBKY0li0aMyXATA=
+github.com/golang/protobuf v1.4.0-rc.2/go.mod h1:LlEzMj4AhA7rCAGe4KMBDvJI+AwstrUpVNzEA03Pprs=
+github.com/golang/protobuf v1.4.0-rc.4.0.20200313231945-b860323f09d0/go.mod h1:WU3c8KckQ9AFe+yFwt9sWVRKCVIyN9cPHBJSNnbL67w=
+github.com/golang/protobuf v1.4.0/go.mod h1:jodUvKwWbYaEsadDk5Fwe5c77LiNKVO9IDvqG2KuDX0=
+github.com/golang/protobuf v1.4.2 h1:+Z5KGCizgyZCbGh1KZqA0fcLLkwbsjIzS4aV2v7wJX0=
+github.com/golang/protobuf v1.4.2/go.mod h1:oDoupMAO8OvCJWAcko0GGGIgR6R6ocIYbsSw735rRwI=
+github.com/google/go-cmp v0.3.0/go.mod h1:8QqcDgzrUqlUb/G2PQTWiueGozuR1884gddMywk6iLU=
+github.com/google/go-cmp v0.3.1/go.mod h1:8QqcDgzrUqlUb/G2PQTWiueGozuR1884gddMywk6iLU=
+github.com/google/go-cmp v0.4.0/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
+golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
+google.golang.org/protobuf v0.0.0-20200109180630-ec00e32a8dfd/go.mod h1:DFci5gLYBciE7Vtevhsrf46CRTquxDuWsQurQQe4oz8=
+google.golang.org/protobuf v0.0.0-20200221191635-4d8936d0db64/go.mod h1:kwYJMbMJ01Woi6D6+Kah6886xMZcty6N08ah7+eCXa0=
+google.golang.org/protobuf v0.0.0-20200228230310-ab0ca4ff8a60/go.mod h1:cfTl7dwQJ+fmap5saPgwCLgHXTUD7jkjRqWcaiX5VyM=
+google.golang.org/protobuf v1.20.1-0.20200309200217-e05f789c0967/go.mod h1:A+miEFZTKqfCUM6K7xSMQL9OKL/b6hQv+e19PK+JZNE=
+google.golang.org/protobuf v1.21.0/go.mod h1:47Nbq4nVaFHyn7ilMalzfO3qCViNmqZ2kzikPIcrTAo=
+google.golang.org/protobuf v1.23.0 h1:4MY060fB1DLGMB/7MBTLnwQUY6+F09GEiz6SsrNqyzM=
+google.golang.org/protobuf v1.23.0/go.mod h1:EGpADcykh3NcUnDUJcl1+ZksZNG86OlYog2l/sGQquU=