当使用dep时，我如何正确地包含protoc的golang协议dep/ptype？

dep init

dep ensure -add github.com/golang/protobuf/protoc-gen-go

dep ensure -add github.com/golang/protobuf/proto

syntax = "proto3";
package ptype;

import "github.com/golang/protobuf/ptypes/struct.proto";

protoc --go_out=. --go_opt=paths=source_relative --go-grpc_out=. --go-grpc_opt=paths=source_relative your_proto_file.proto

package main

import (
    "fmt"
    "log"

    "github.com/golang/protobuf/proto"
    "github.com/golang/protobuf/ptypes/struct"
)

func main() {
    // 创建一个Struct类型
    s := &structpb.Struct{
        Fields: map[string]*structpb.Value{
            "key": {
                Kind: &structpb.Value_StringValue{
                    StringValue: "value",
                },
            },
        },
    }

    // 序列化Struct为字节流
    data, err := proto.Marshal(s)
    if err != nil {
        log.Fatal(err)
    }

    // 反序列化字节流为Struct
    s2 := &structpb.Struct{}
    if err := proto.Unmarshal(data, s2); err != nil {
        log.Fatal(err)
    }

    fmt.Println(s2)
}