proto 声明SayHi 

先删除go.mod  从新初始化一下

go mod init xgs_kratos

go mod tidy

编辑 api/helloword/v1/greeter.proto 新声明一个方法

rpc SayHi (HelloHiRequest) returns (HelloHiReply) {
    option (google.api.http) = {
      post: "/hi"
      body: "*"
    };
  }

post请求的话 body必须写，定义好之后 

#执行
make api

#在执行
make generate

编辑service层

package service

import (
	"context"

	v1 "xgs_kratos/api/helloworld/v1"
	"xgs_kratos/internal/biz"
)

// GreeterService is a greeter service.
type GreeterService struct {
	v1.UnimplementedGreeterServer

	uc *biz.GreeterUsecase
}

// NewGreeterService new a greeter service.
func NewGreeterService(uc *biz.GreeterUsecase) *GreeterService {
	return &GreeterService{uc: uc}
}

// SayHello implements helloworld.GreeterServer.
func (s *GreeterService) SayHello(ctx context.Context, in *v1.HelloRequest) (*v1.HelloReply, error) {
	g, err := s.uc.CreateGreeter(ctx, &biz.Greeter{Hello: in.Name})
	if err != nil {
		return nil, err
	}
	return &v1.HelloReply{Message: "Hello " + g.Hello}, nil
}

// SayHi implements helloworld.GreeterServer.
func (s *GreeterService) SayHi(ctx context.Context, in *v1.HelloHiRequest) (*v1.HelloHiReply, error) {
	g, err := s.uc.CreateGreeter(ctx, &biz.Greeter{Hello: in.Name})
	if err != nil {
		return nil, err
	}
	return &v1.HelloHiReply{Message: "Hello " + g.Hello}, nil
}

运行 kratos run

postman请求的结果如下