protoc-gen-micro
This is protobuf code generation for micro. We use protoc-gen-micro to reduce boilerplate code.
Install
go get github.com/micro/protoc-gen-micro/v2
Also required:
Usage
Define your service as greeter.proto
syntax = "proto3";
service Greeter {
rpc Hello(Request) returns (Response) {}
}
message Request {
string name = 1;
}
message Response {
string msg = 1;
}
Generate the code
protoc --proto_path=$GOPATH/src:. --micro_out=. --go_out=. greeter.proto
Your output result should be:
./
greeter.proto # original protobuf file
greeter.pb.go # auto-generated by protoc-gen-go
greeter.micro.go # auto-generated by protoc-gen-micro
The micro generated code includes clients and handlers which reduce boiler plate code
Server
Register the handler with your micro server
type Greeter struct{}
func (g *Greeter) Hello(ctx context.Context, req *proto.Request, rsp *proto.Response) error {
rsp.Msg = "Hello " + req.Name
return nil
}
proto.RegisterGreeterHandler(service.Server(), &Greeter{})
Client
Create a service client with your micro client
client := proto.NewGreeterService("greeter", service.Client())
Errors
If you see an error about protoc-gen-micro
not being found or executable, it's likely your environment may not be configured correctly. If you've already installed protoc
, protoc-gen-go
, and protoc-gen-micro
ensure you've included $GOPATH/bin
in your PATH
.
Alternative specify the Go plugin paths as arguments to the protoc
command
protoc --plugin=protoc-gen-go=$GOPATH/bin/protoc-gen-go --plugin=protoc-gen-micro=$GOPATH/bin/protoc-gen-micro --proto_path=$GOPATH/src:. --micro_out=. --go_out=. greeter.proto
Endpoint
Add a micro API endpoint which routes directly to an RPC method
Usage:
- Clone
github.com/googleapis/googleapis
to use this feature as it requires http annotations. - The protoc command must include
-I$GOPATH/src/github.com/googleapis/googleapis
for the annotations import.
syntax = "proto3";
import "google/api/annotations.proto";
service Greeter {
rpc Hello(Request) returns (Response) {
option (google.api.http) = { post: "/hello"; body: "*"; };
}
}
message Request {
string name = 1;
}
message Response {
string msg = 1;
}
The proto generates a RegisterGreeterHandler
function with a api.Endpoint.
func RegisterGreeterHandler(s server.Server, hdlr GreeterHandler, opts ...server.HandlerOption) error {
type greeter interface {
Hello(ctx context.Context, in *Request, out *Response) error
}
type Greeter struct {
greeter
}
h := &greeterHandler{hdlr}
opts = append(opts, api.WithEndpoint(&api.Endpoint{
Name: "Greeter.Hello",
Path: []string{"/hello"},
Method: []string{"POST"},
Handler: "rpc",
}))
return s.Handle(s.NewHandler(&Greeter{h}, opts...))
}
LICENSE
protoc-gen-micro is a liberal reuse of protoc-gen-go hence we maintain the original license