go grpc中间件

go grpc中间件

本例为查询“计量单位”。

编辑 units.proto

syntax="proto3";
package main;

message Units {
string unitid = 1;
string unitname = 2;
}

message Unitss {
repeated Units UnitsArr = 1;
}

message UnitsRequest {
  string dbid = 1;
} 

service UnitsService{
  rpc UnitsQry(UnitsRequest) returns(Unitss);
}

根据 units.proto自动生成go代码

protoc --gofast_out=plugins=grpc:./ ./units.proto

服务端

// svrgrpc project main.go
//cxg 2021-9-25

package main

import (
    "fmt"
    "net"

    "context"

    "google.golang.org/grpc"
)

type server struct{}

func (s *server) UnitsQry(ctx context.Context, in *UnitsRequest) (*Unitss, error) {
    fmt.Println("request: ", in.Dbid)
    var u Units
    u.Unitid = "1"
    u.Unitname = "个"
    var us Unitss
    us.UnitsArr = append(us.UnitsArr, &u)
    return &us, nil
}

func main() {
    listen, err := net.Listen("tcp", ":7070")
    if err != nil {
        fmt.Println("failed to listen: %v", err)
    }
    s := grpc.NewServer()
    RegisterUnitsServiceServer(s, &server{})
    fmt.Println("咏南grpc服务已经开启")
    s.Serve(listen)
}

go客户端

// clientgrpc project main.go
package main

import (
    "context"
    "fmt"

    "google.golang.org/grpc"
)

const (
    address = "localhost:7070"
)

func main() {
    conn, err := grpc.Dial(address, grpc.WithInsecure())

    if err != nil {
        fmt.Println("did not connect: %v", err)
    }

    defer conn.Close()

    c := NewUnitsServiceClient(conn)

    r, err := c.UnitsQry(context.Background(), &UnitsRequest{Dbid: "1"})

    if err != nil {
        fmt.Println("could not greet: %v", err)
    }
    fmt.Println(r.UnitsArr[0].Unitid, r.UnitsArr[0].Unitname)
}

凡支持gRPC客户端的其他语言都可以调用。