在校生的萬(wàn)字長(zhǎng)文：gRPC 實(shí)操指南（golang）

func sum(num1,num2 int) int {
  return num1 + num2
}

A high-performance, open-source universal RPC framework

 go get google.golang.org/grpc

go get -u github.com/golang/protobuf/protoc-gen-go

//指定使用proto3（proto2，3有很多不同，不可混寫）
syntax = "proto3";
//指定生成的go_package,簡(jiǎn)單來(lái)說就是生成的go代碼使用什么包，即package proto
option go_package = ".;proto";

//定義rpc服務(wù)
//此處rpc服務(wù)的定義，一定要從服務(wù)端的角度考慮，即接受請(qǐng)求，處理請(qǐng)求并返回響應(yīng)的一端
//請(qǐng)求接受一個(gè)LoginReq（username+password)
//響應(yīng)回發(fā)一條msg（"true" or "false")
service Login{
  rpc Login(LoginReq)returns(LoginRes){}
}

message LoginReq {
  string username = 1;
  string password = 2;
}

message LoginRes {
  string msg = 1;
}

syntax = "proto3";
option go_package = ".;proto";

//下載服務(wù)
//請(qǐng)求接受一個(gè)UploadReq（username+password)
//響應(yīng)回發(fā)多條數(shù)據(jù)（"true" or "false")
service Upload{
  rpc Upload(stream UploadReq)returns(UploadRes){}
}

message UploadReq {
  string path = 1;
  int64 offset = 2;
  int64 size = 3;
  bytes data = 4;
}

message UploadRes {
  string msg = 1;
}

syntax = "proto3";
option go_package = ".;proto";

//下載服務(wù)
//請(qǐng)求接受一個(gè)DownloadReq（username+password)
//響應(yīng)回發(fā)多條數(shù)據(jù)（"true" or "false")
service Download{
  rpc Download(DownloadReq)returns(stream DownloadRes){}
}

message DownloadReq {
  string path = 1;
  int64 offset = 2;
  int64 size = 3;
}

message DownloadRes {
  int64 offset = 1;
  int64 size = 2;
  bytes data = 3;
}

 protoc --go_out=plugins=grpc:. *.proto

// LoginClient is the client API for Login service.
//
// For semantics around ctx use and closing/ending streaming RPCs, please refer to https://godoc.org/google.golang.org/grpc#ClientConn.NewStream.
type LoginClient interface {
    Login(ctx context.Context, in *LoginReq, opts ...grpc.CallOption) (*LoginRes, error)
}

// LoginServer is the server API for Login service.
type LoginServer interface {
    Login(context.Context, *LoginReq) (*LoginRes, error)
}

package main

import (
    "context"
    "grpcExample/simple_rpc/proto"
)

type LoginServer struct {}

//判斷用戶名，密碼是否為root,123456，驗(yàn)證正確即返回
func (*LoginServer)Login(ctx context.Context, req *proto.LoginReq) (*proto.LoginRes, error) {
    //為降低復(fù)雜度，此處不對(duì)ctx進(jìn)行處理
    if req.Username == "root" && req.Password == "123456" {
        return &proto.LoginRes{Msg: "true"},nil
    } else {
        return &proto.LoginRes{Msg: "false"},nil
    }
}

package main

import (
    "grpcExample/client_stream_rpc/proto"
    "io"
    "log"
)

type UploadServer struct{}

func (*UploadServer) Upload(uploadServer proto.Upload_UploadServer) error {
    for {
        //循環(huán)接受客戶端傳的流數(shù)據(jù)
        recv, err := uploadServer.Recv()
        //檢測(cè)到EOF（客戶端調(diào)用close）
        if err == io.EOF {
            //發(fā)送res
            err := uploadServer.SendAndClose(&proto.UploadRes{Msg: "finish"})
            if err != nil {
                return err
            }
            return nil
        } else if err != nil{
            return err
        }
        log.Printf("get a upload data package~ offset:%v, size:%v\n",recv.Offset,recv.Size)
    }
}

package main

import (
    "grpcExample/server_stream_rpc/proto"
    "log"
)

type DownloadServer struct{}

func (*DownloadServer) Download(req *proto.DownloadReq, downloadServer proto.Download_DownloadServer) error {
    offset := req.Offset
    //循環(huán)發(fā)送數(shù)據(jù)
    for {
        err := downloadServer.Send(&proto.DownloadRes{
            Offset: offset,
            Size:   4 * 1024,
            Data:   nil,
        })
        if err != nil {
            return err
        }
        offset += 4 * 1024
        if offset >= req.Offset + req.Size {
            break
        }
    }
    return nil
}

func main() {
    lis, err := net.Listen("tcp", ":6012")
    if err != nil {
        log.Fatalf("failed to listen: %v", err)
    }

    //構(gòu)建一個(gè)新的服務(wù)端對(duì)象
    s := grpc.NewServer()
    //向這個(gè)服務(wù)端對(duì)象注冊(cè)服務(wù)
    proto.RegisterDownloadServer(s,&DownloadServer{})
    //注冊(cè)服務(wù)端反射服務(wù)
    reflection.Register(s)

    //啟動(dòng)服務(wù)
    s.Serve(lis)

    //可配合ctx實(shí)現(xiàn)服務(wù)端的動(dòng)態(tài)終止
    //s.Stop()
}

package main

import (
    "context"
    "google.golang.org/grpc"
    "grpcExample/simple_rpc/proto"
    "log"
    "time"
)

func main() {
    //創(chuàng)立grpc連接
    grpcConn, err := grpc.Dial("127.0.0.1"+":6012", grpc.WithInsecure())
    if err != nil {
        log.Fatalln(err)
    }

    //通過grpc連接創(chuàng)建一個(gè)客戶端實(shí)例對(duì)象
    client := proto.NewLoginClient(grpcConn)

    //設(shè)置ctx超時(shí)（根據(jù)情況設(shè)定）
    ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
    defer cancel()

    //通過client客戶端對(duì)象，調(diào)用Login函數(shù)
    res, err := client.Login(ctx, &proto.LoginReq{
        Username: "root",
        Password: "123456",
    })
    if err != nil {
        log.Fatalln(err)
    }

    //輸出登陸結(jié)果
    log.Println("the login answer is", res.Msg)
}

package main

import (
    "context"
    "google.golang.org/grpc"
    "grpcExample/client_stream_rpc/proto"
    "log"
    "time"
)

func main(){
    //創(chuàng)立grpc連接
    grpcConn, err := grpc.Dial("127.0.0.1"+":6012", grpc.WithInsecure())
    if err != nil {
        log.Fatalln(err)
    }

    //通過grpc連接創(chuàng)建一個(gè)客戶端實(shí)例對(duì)象
    client := proto.NewUploadClient(grpcConn)

    //設(shè)置ctx超時(shí)（根據(jù)情況設(shè)定）
    ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
    defer cancel()

    //和簡(jiǎn)單rpc不同，此時(shí)獲得的不是res，而是一個(gè)client的對(duì)象，通過這個(gè)連接對(duì)象去發(fā)送數(shù)據(jù)
    uploadClient,err := client.Upload(ctx)
    if err != nil {
        log.Fatalln(err)
    }

    var offset int64
    var size int64
    size = 4 * 1024

    //循環(huán)處理數(shù)據(jù)，當(dāng)大于64kb退出
    for {
        err := uploadClient.Send(&proto.UploadReq{
            Path:   "../test.txt",
            Offset: offset,
            Size:   size,
            Data:   nil,
        })
        if err != nil {
            log.Fatalln(err)
        }
        offset += size
        //發(fā)送超過64KB，調(diào)用CloseAndRecv方法接收response
        if offset >= 64 * 1024 {
            res, err := uploadClient.CloseAndRecv()
            if err != nil {
                log.Fatalln(err)
            }
            log.Println("upload over~, response is ",res.Msg)
            break
        }
    }
}

package main

import (
    "context"
    "google.golang.org/grpc"
    "grpcExample/server_stream_rpc/proto"
    "log"
    "time"
)

func main(){
    //創(chuàng)立grpc連接
    grpcConn, err := grpc.Dial("127.0.0.1"+":6012", grpc.WithInsecure())
    if err != nil {
        log.Fatalln(err)
    }

    //通過grpc連接創(chuàng)建一個(gè)客戶端實(shí)例對(duì)象
    client := proto.NewDownloadClient(grpcConn)

    //設(shè)置ctx超時(shí)（根據(jù)情況設(shè)定）
    ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
    defer cancel()

    //和簡(jiǎn)單rpc不同，此時(shí)獲得的不是res，而是一個(gè)client的對(duì)象，通過這個(gè)連接對(duì)象去讀取數(shù)據(jù)
    downloadClient,err := client.Download(ctx,&proto.DownloadReq{
        Path:   "../test.txt",
        Offset: 0,
        Size:   64 * 1024,
    })
    if err != nil {
        log.Fatalln(err)
    }

    //循環(huán)處理數(shù)據(jù)，當(dāng)監(jiān)測(cè)到讀取完成后退出
    for {
        res, err := downloadClient.Recv()
        if err != nil {
            log.Fatalln(err)
        }
        log.Printf("get a date package~ offset:%v, size:%v\n",res.Offset,res.Size)
        if res.Size + res.Offset >= 64 * 1024 {
            break
        }
    }

    log.Println("download over~")
}