Before using protoc-gen-go-dubbo, make sure you have the following prerequisites installed on your system:
- Go (version 1.17 or higher)
- Protocol Buffers (version 3.0 or higher)
To install protoc-gen-go-dubbo, you can use go install:
go install github.com/dubbogo/protoc-gen-go-dubboOr you can clone this repository and build it manually:
git clone github.com/dubbogo/protoc-gen-go-dubbo
cd protoc-gen-go-dubbo
go buildTo generate dubbo code using protoc-gen-go-dubbo, you can use the following command:
protoc -I ./ \
--go-dubbo_out=./ --go-dubbo_opt=paths=source_relative \
./greet.protoThe --go-dubbo_out option specifies the output directory for the generated code,
and --go-dubbo_opt=paths=source_relative sets the output path to be relative to the source file.
To generate Dubbo code, you can create a .proto file with the following content:
syntax = "proto3";
package greet;
option go_package = "some_path/greet;greet";
import "unified_idl_extend/unified_idl_extend.proto";
message GreetRequest {
string name = 1;
option (unified_idl_extend.message_extend) = {
java_class_name: "org.apache.greet.GreetRequest";
};
}
message GreetResponse {
string greeting = 1;
option (unified_idl_extend.message_extend) = {
java_class_name: "org.apache.greet.GreetResponse";
};
}
service GreetService {
rpc Greet(GreetRequest) returns (GreetResponse) {
option (unified_idl_extend.method_extend) = {
method_name: "greet";
};
}
}Note that you need to import the unified_idl_extend package to use the method_extend options to extend the service.
And Dubbo protocol must be used with Hessian2 serialization, so you need to use the message_extend options to extend
the message.
Then, you can run the following command to generate the Dubbo and Hessian2 code:
protoc -I ./ \
--go-hessian2_out=./ --go-hessian2_opt=paths=source_relative \
--go-dubbo_out=./ --go-dubbo_opt=paths=source_relative \
./greet.protoThis will generate the greet.dubbo.go and greet.hessian2.go file in the same directory as your greet.proto file:
.
├── greet.hessian2.go
├── greet.dubbo.go
├── greet.proto
└── unified_idl_extend
├── unified_idl_extend.pb.go
└── unified_idl_extend.protoThe content of the greet.hessian2.go file will be:
// Code generated by protoc-gen-go-dubbo. DO NOT EDIT.
// Source: greet.proto
// Package: greet
package greet
import (
"context"
"dubbo.apache.org/dubbo-go/v3"
"dubbo.apache.org/dubbo-go/v3/client"
"dubbo.apache.org/dubbo-go/v3/common"
"dubbo.apache.org/dubbo-go/v3/common/constant"
"dubbo.apache.org/dubbo-go/v3/server"
)
const (
// GreetServiceName is the fully-qualified name of the GreetService service.
GreetServiceName = "greet.GreetService"
// These constants are the fully-qualified names of the RPCs defined in this package. They're
// exposed at runtime as procedure and as the final two segments of the HTTP route.
//
// Note that these are different from the fully-qualified method names used by
// google.golang.org/protobuf/reflect/protoreflect. To convert from these constants to
// reflection-formatted method names, remove the leading slash and convert the remaining slash to a
// period.
// GreetServiceGreetProcedure is the fully-qualified name of the GreetService's Greet RPC.'
GreetServiceGreetProcedure = "/greet.GreetService/greet"
)
var (
_ GreetService = (*GreetServiceImpl)(nil)
)
type GreetService interface {
Greet(ctx context.Context, req *GreetRequest, opts ...client.CallOption) (*GreetResponse, error)
}
// NewGreetService constructs a client for the greet.GreetService service
func NewGreetService(cli *client.Client, opts ...client.ReferenceOption) (GreetService, error) {
conn, err := cli.DialWithInfo("greet.GreetService", &GreetService_ClientInfo, opts...)
if err != nil {
return nil, err
}
return &GreetServiceImpl{
conn: conn,
}, nil
}
func SetConsumerService(srv common.RPCService) {
dubbo.SetConsumerServiceWithInfo(srv, &GreetService_ClientInfo)
}
// GreetServiceImpl implements GreetService
type GreetServiceImpl struct {
conn *client.Connection
}
func (c *GreetServiceImpl) Greet(ctx context.Context, req *GreetRequest, opts ...client.CallOption) (*GreetResponse, error) {
resp := new(GreetResponse)
if err := c.conn.CallUnary(ctx, []interface{}{req}, resp, "greet", opts...); err != nil {
return nil, err
}
return resp, nil
}
var GreetService_ClientInfo = client.ClientInfo{
InterfaceName: "greet.GreetService",
MethodNames: []string{
"greet",
},
ConnectionInjectFunc: func(dubboCliRaw interface{}, conn *client.Connection) {
dubboCli := dubboCliRaw.(*GreetServiceImpl)
dubboCli.conn = conn
},
}
// GreetServiceHandler is an implementation of the greet.GreetService service.
type GreetServiceHandler interface {
Greet(ctx context.Context, req *GreetRequest) (*GreetResponse, error)
}
func RegisterGreetServiceHandler(srv *server.Server, hdlr GreetServiceHandler, opts ...server.ServiceOption) error {
return srv.Register(hdlr, &GreetService_ServiceInfo, opts...)
}
func SetProviderService(srv common.RPCService) {
dubbo.SetProviderServiceWithInfo(srv, &GreetService_ServiceInfo)
}
var GreetService_ServiceInfo = server.ServiceInfo{
InterfaceName: "greet.GreetService",
ServiceType: (*GreetServiceHandler)(nil),
Methods: []server.MethodInfo{
{
Name: "greet",
Type: constant.CallUnary,
ReqInitFunc: func() interface{} {
return new(GreetResponse)
},
MethodFunc: func(ctx context.Context, args []interface{}, handler interface{}) (interface{}, error) {
req := args[0].(*GreetRequest)
res, err := handler.(GreetServiceHandler).Greet(ctx, req)
return res, err
},
},
},
}