从protobuf中的其他包导入类型定义

Question

I am trying to create a grpc service with a very basic single action which is GetDeployment, takes a namespace and a name as an input, and returns a Kubernetes deployment. The thing is that I do not want to define my own message for the Deployment as it already exists on the official Kubernetes repository.

I am pretty new to grpc and probably do not understand well enough how it works but can I import this message to my own file in a way I could then write the following .proto file ?

syntax = "proto3";
package api;

import "google/api/annotations.proto";
import "k8s.io/kubernetes/pkg/api/v1/generated.proto";

message GetDeploymentOptions {
  string namespace = 1;
  string name = 2;
}

service AppsV1 {
  rpc GetDeployment(GetDeploymentOptions) returns (k8s.io.kubernetes.pkg.api.v1.Deployment) {}
}

Thank you in advance

Answer 1

GRPC codegen is just a protoc plugin. It generates code for service and rpc but it follows the normal protobuf rules for imports.

In your example, if your file is in src/api.proto and the k8s api repo is a git submodule checked out into thirdparty/k8s.io/api folder you would generate the files you'd need by running:

root>protoc.exe -I thirdparty k8s.io/api/core/v1/generated.proto --go_out=go
root>protoc.exe -I thirdparty src/api.proto --go_out=plugins=grpc:go

The first command is generating the .pb.go file which contains the k8s messages, while the second command is generating the .pb.go file which contains your messages and your service.

Looking at the transient imports of that file, you may also need to checkout api-machinery into k8s.io/apimachinery and run protoc on that file as well.