grpc-gateway-example/service/echo/v1/echo.go

package echo

import (
	"context"

	"google.golang.org/grpc/codes"
	"google.golang.org/grpc/status"
	"google.golang.org/protobuf/types/known/timestamppb"

	pb "github.com/esinio/geco/gen/proto/echo/v1"
)

type Service struct {
	pb.UnimplementedEchoServiceServer
}

func NewService() *Service {
	return &Service{}
}

func (s *Service) Echo(ctx context.Context, req *pb.StringMessage) (*pb.StringMessage, error) {
	if req.Value == "" {
		return nil, status.Errorf(codes.Unimplemented, "value is empty")
	}
	return &pb.StringMessage{
		Value:     req.Value,
		Timestamp: timestamppb.Now(),
	}, nil
}