使用gRPC-Gateway快速建構微服務-雙向認證下rpc-gateway使用（同時提供rpc和http接口）

https://github.com/grpc-ecosystem/grpc-gateway

 在grpc之上加一層代理并轉發，轉變成protobuf格式來通路grpc服務

安裝

go get -u github.com/grpc-ecosystem/grpc-gateway/protoc-gen-grpc-gateway
go get -u github.com/grpc-ecosystem/grpc-gateway/protoc-gen-swagger
go get -u github.com/golang/protobuf/protoc-gen-go      

Prod.proto

syntax="proto3";
package services;
import "google/api/annotations.proto";

message  ProdRequest {
    int32 prod_id =1;   //傳入的商品ID
}
message ProdResponse{
    int32 prod_stock=1;//商品庫存
}

service ProdService {
    rpc GetProdStock (ProdRequest) returns (ProdResponse){
        option (google.api.http) = {
            get: "/v1/prod/{prod_id}"
        };

    }
}      

生成兩個檔案

首先cd 進入pbfiles

這會生成Prod.pb.go
protoc --go_out=plugins=grpc:../services  Prod.proto


這會生成Prod.pb.gw.go
protoc  --grpc-gateway_out=logtostderr=true:../services Prod.proto      

httpserver.go

package main

import (
    "context"
    "github.com/grpc-ecosystem/grpc-gateway/runtime"
    "google.golang.org/grpc"
    "grpcpro/services"
    "log"
    "net/http"
)

func main()  {
    gwmux:=runtime.NewServeMux()
    opt := []grpc.DialOption{grpc.WithInsecure()}
    err:=services.RegisterProdServiceHandlerFromEndpoint(context.Background(),
        gwmux,"localhost:8081",opt)
    if err != nil {
        log.Fatal(err)
    }
    httpServer:=&http.Server{
        Addr:":8080",
        Handler:gwmux,
    }
    httpServer.ListenAndServe()

}      

server.go

package main

import (
    "google.golang.org/grpc"
    "grpcpro/services"
    "net"
)

func main()  {
    rpcServer:=grpc.NewServer()
    services.RegisterProdServiceServer(rpcServer,new(services.ProdService))

    lis,_:=net.Listen("tcp",":8081")

    rpcServer.Serve(lis)


}