✨ feat: Day7 使用 Protobuf 通信

1. 使用 Protobuf 通信
2. 添加运行脚本

README.md

@@ -1,14 +1,22 @@
 ## 分布式缓存
 
-#### 一致性哈希
+1.为了解决资源限制的问题，实现了 LRU 缓存淘汰算法
 
-对于给定的 key，每次都选择同一个节点
+2.实现了单机并发，并给用户提供了自定义数据源的回调函数
+
+3.实现了 HTTP 服务端
+
+4.实现了一致性哈希算法，解决远程节点的挑选问题
 
-节点固定时：
+5.创建 HTTP 客户端，实现了多节点间的通信
 
-把 key 的每一个字符的 ASCII 码加起来，除以 10 取余数
+6.实现了 singleflight 解决缓存击穿的问题
 
-hash('Tom') % 10
+7.使用 protobuf 库，优化了节点间通信的性能
+
+#### 一致性哈希
+
+对于给定的 key，每次都选择同一个节点
 
 #### 防止缓存击穿
 

geecache.go

@@ -2,6 +2,7 @@ package geecache
 
 import (
  "fmt"
+ "geecache/pb"
  "geecache/singleflight"
  "log"
  "sync"
@@ -109,11 +110,17 @@ func (g *Group) load(key string) (value ByteView, err error) {
 
 // getFromPeer 使用实现了 PeerGetter 接口的 httpGetter 从访问远程节点，获取缓存值
 func (g *Group) getFromPeer(peer PeerGetter, key string) (ByteView, error) {
- bytes, err := peer.Get(g.name, key)
+ // bytes, err := peer.Get(g.name, key)
+ req := &pb.Request{
+ Group: g.name,
+ Key: key,
+ }
+ res := &pb.Response{}
+ err := peer.Get(req, res)
  if err != nil {
  return ByteView{}, err
  }
- return ByteView{b: bytes}, nil
+ return ByteView{b: res.Value}, nil
 }
 
 func (g *Group) getLocally(key string) (ByteView, error) {

go.mod

@@ -1,3 +1,5 @@
 module geecache
 
 go 1.18
+
+require google.golang.org/protobuf v1.28.0 // indirect

go.sum

@@ -0,0 +1,6 @@
+github.com/golang/protobuf v1.5.0/go.mod h1:FsONVRAS9T7sI+LIUmWTfcYkHO4aIWwzhcaSAoJOfIk=
+github.com/google/go-cmp v0.5.5/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 v1.26.0-rc.1/go.mod h1:jlhhOSvTdKEhbULTjvd4ARK9grFBp09yW+WbY/TyQbw=
+google.golang.org/protobuf v1.28.0 h1:w43yiav+6bVFTBQFZX0r7ipe9JQ1QsbMgHwbBziscLw=
+google.golang.org/protobuf v1.28.0/go.mod h1:HV8QOd/L58Z+nl8r43ehVNZIU/HEI6OcFqwMG9pJV4I=

http.go

@@ -3,12 +3,15 @@ package geecache
 import (
  "fmt"
  "geecache/consistenthash"
+ "geecache/pb"
  "io/ioutil"
  "log"
  "net/http"
  "net/url"
  "strings"
  "sync"
+
+ "google.golang.org/protobuf/proto"
 )
 
 const (
@@ -62,14 +65,13 @@ func (p *HTTPPool) ServeHTTP(w http.ResponseWriter, r *http.Request) {
  }
 
  view, err := group.Get(key)
+ body, err := proto.Marshal(&pb.Response{Value: view.ByteSlice()})
  if err != nil {
  http.Error(w, err.Error(), http.StatusInternalServerError)
  return
  }
-
  w.Header().Set("Content-Type", "application/octet-stream")
- w.Write(view.ByteSlice())
- // log.Println(view.ByteSlice())
+ w.Write(body)
 }
 
 // Set updates the pool's list of peers
@@ -101,29 +103,33 @@ type httpGetter struct {
  baseURL string
 }
 
-func (h *httpGetter) Get(group string, key string) ([]byte, error) {
+func (h *httpGetter) Get(in *pb.Request, out *pb.Response) error {
  u := fmt.Sprintf(
  "%v%v/%v",
  h.baseURL,
- url.QueryEscape(group),
- url.QueryEscape(key),
+ url.QueryEscape(in.GetGroup()),
+ url.QueryEscape(in.GetKey()),
  )
  res, err := http.Get(u)
  if err != nil {
- return nil, err
+ return err
  }
  defer res.Body.Close()
 
  if res.StatusCode != http.StatusOK {
- return nil, fmt.Errorf("server returned: %v", res.Status)
+ return fmt.Errorf("server returned: %v", res.Status)
  }
 
  bytes, err := ioutil.ReadAll(res.Body)
  if err != nil {
- return nil, fmt.Errorf("reading response body: %v", err)
+ return fmt.Errorf("reading response body: %v", err)
+ }
+
+ if err = proto.Unmarshal(bytes, out); err != nil {
+ return fmt.Errorf("decoding response body: %v", err)
  }
 
- return bytes, nil
+ return nil
 }
 
 var _ PeerGetter = (*httpGetter)(nil)

main/run.sh

@@ -0,0 +1,14 @@
+trap "rm cache_server;kill 0" EXIT
+
+go build -o cache_server.exe
+./cache_server.exe -port=8001 &
+./cache_server.exe -port=8002 &
+./cache_server.exe -port=8003 -api=1&
+
+sleep 2
+echo ">>> start test"
+curl "http:https://localhost:9999/api?key=Tom" &
+curl "http:https://localhost:9999/api?key=Tom" &
+curl "http:https://localhost:9999/api?key=Tom" &
+
+wait

pb/pb.proto

@@ -0,0 +1,18 @@
+syntax = "proto3";
+
+package pb;
+
+option go_package = "../pb";
+
+message Request {
+ string group = 1;
+ string key = 2;
+}
+
+message Response {
+ bytes value = 1;
+}
+
+service GroupCache {
+ rpc Get(Request) returns (Response);
+}