如何统一 grpc-gateway 响应的外层结构？

基于 Gin 实现一个对外网关，做协议转换，向内部发起grpc调用，成功就直接扔data里包装返回给前端，失败处理 error，然后组装一个 error response 给前端就行了，核心思路就是自己实现把 http url 做分割，比如 /package.version/service/method，然后用 github.com/jhump/protoreflect 加载本地的proto文件，基于 package 信息拿到 service 信息，然后拿到 method 以及具体的 request message ，动态创建一个 message，动态创建 stub，然后发起调用就行了

import (
    "context"
    "encoding/json"
    "github.com/grpc-ecosystem/grpc-gateway/v2/runtime"
    "google.golang.org/protobuf/encoding/protojson"
    "io"
)

// Custom Marshaler

type CustomMarshaler struct {
    m *runtime.JSONPb
}

type Response struct {
    Code    uint        `json:"code"`
    Message string      `json:"message"`
    Data    interface{} `json:"data"`
}

func (c *CustomMarshaler) Marshal(v interface{}) ([]byte, error) {
    return c.m.Marshal(&Response{
        Code:    200,
        Message: "successful",
        Data:    v,
    })
}
func (c *CustomMarshaler) Unmarshal(data []byte, v interface{}) error {
    return c.m.Unmarshal(data, v)
}

func (c *CustomMarshaler) NewDecoder(r io.Reader) runtime.Decoder {
    return c.m.NewDecoder(r)
}
func (c *CustomMarshaler) NewEncoder(w io.Writer) runtime.Encoder {
    return c.m.NewEncoder(w)
}
func (c *CustomMarshaler) ContentType(v interface{}) string {
    return "application/json"
}

opts := []runtime.ServeMuxOption{
    runtime.WithMarshalerOption(runtime.MIMEWildcard, &runtime.HTTPBodyMarshaler{
        Marshaler: &CustomMarshaler{
            m: &runtime.JSONPb{
                MarshalOptions:   protojson.MarshalOptions{},
                UnmarshalOptions: protojson.UnmarshalOptions{},
            }},
    }),
}

gws := runtime.NewServeMux(opts...)