type Request struct {
    Name string `path:"name,options=you|me"`
}
type Response struct {
    Message string `json:"message"`
}
service A-api {
    @handler NormalHandler
    get /greet/from/:name(Request) returns (Response)
    @handler NoResponseHandler
    get /greet/from/:sex(Request)
    @handler NoRequestHandler
    get /greet/from/request returns (Response)
    @handler NoRequestNoResponseHandler
    get /greet/from
}