【轻知识】Go grpc的实现

前情回顾

继上篇《【轻知识】（糙译）Go使用proto3、官方示例代码》，我根据官方demo生成了一个文件 addressbook.data 。

正好grpc的实现，也别浪费了这个demo。还记得那个proto文件么？ addressbook.proto 。实现rpc呢？我需要简单的更改下文件。增加Service

贴代码

温馨提示:

记得 go get -u google.golang.org/grpc

protoc addressbook.proto --go_out=plugins=grpc:./ 如果不加grpc就没有rpc代码实现

不加grpc跟加了的对比

image.png

proto 文件如下

syntax = "proto3";
package tutorial;

import "google/protobuf/timestamp.proto";

message Person {
    string name  = 1;
    int32 id = 2;
    string email = 3;

    enum PhoneType {
        MOBILE = 0;
        HOME = 1;
        WORK = 2;
    }
    message PhoneNumber {
        string number = 1;
        PhoneType type =2;
    }
    repeated PhoneNumber phones = 4;
    google.protobuf.Timestamp last_updated = 5;
}

message AddressBook {
    repeated Person people = 1;
}

message AddressListRequest {
    int32 page = 1;
}
message AddressListResponse {
    AddressBook book_list = 1;
}
service AddressListService {
    rpc AddressList (AddressListRequest) returns (AddressListResponse);
}

接着看服务器端代码：

读取addressbook.data（正好没浪费）

package main

import (
    "context"
    "fmt"
    "io/ioutil"
    "log"
    "net"
    pb "rpc/tutorial"

    "github.com/golang/protobuf/proto"
    "google.golang.org/grpc"
    "google.golang.org/grpc/reflection"
)

type server struct{}

func (s *server) AddressList(ctx context.Context, in *pb.AddressListRequest) (*pb.AddressListResponse, error) {
    fileData, err := ioutil.ReadFile("./addressbook.data")
    if err != nil {
        log.Fatalln("Error reading file:", err)
    }
    book := &pb.AddressBook{}
    if err := proto.Unmarshal(fileData, book); err != nil {
        log.Fatalln("Failed to parse address book:", err)
    }
    fmt.Printf("%v\n", book)
    return &pb.AddressListResponse{BookList: book}, nil
}

func main() {
    s := grpc.NewServer()
    pb.RegisterAddressListServiceServer(s, &server{})
    reflection.Register(s)
    lis, err := net.Listen("tcp", ":9555")
    if err != nil {
        log.Println(err)
    }
    if err := s.Serve(lis); err != nil {
        log.Fatalf("failed to serve: %s", err)
    }
}

client端代码

package main

import (
    "context"
    "encoding/json"
    "fmt"
    "log"
    pb "rpc/tutorial"
    "time"

    "google.golang.org/grpc"
)

func main() {
    conn, err := grpc.Dial("127.0.0.1:9555", grpc.WithInsecure())
    if err != nil {
        log.Fatalf("did not connect: %v", err)
    }
    defer conn.Close()
    c := pb.NewAddressListServiceClient(conn)
    ctx, cancel := context.WithTimeout(context.Background(), time.Second)
    defer cancel()
    r, err := c.AddressList(ctx, &pb.AddressListRequest{Page: 1})
    if err != nil {
        log.Fatalf("could not greet: %v", err)
    }
    json, err := json.Marshal(r.BookList)
    if err != nil {
        panic(err)
    }
    fmt.Printf("%v", string(json))

}

执行client端代码输出

{
    "people":[
        {
            "name":"mike",
            "id":123,
            "email":"mike@gmail.com",
            "phones":[
                {
                    "number":"178933"
                }
            ]
        },
        {
            "name":"mike",
            "id":123434,
            "email":"mike@gmail.com",
            "phones":[
                {
                    "number":"178933",
                    "type":1
                },
                {
                    "number":"98783",
                    "type":2
                },
                {
                    "number":"123333"
                }
            ]
        }
    ]
}

参考资料：

• 《grpc/grpc-go》 https://github.com/grpc/grpc-go/tree/master/examples
• 《grpc Tutorials》 https://grpc.io/docs/tutorials/