Json 将 io.ReadCloser 转换为字节数组的最有效方法

I have a very simple Go webserver. It's job is to receive an inbound json payload. It then publishes the payload to one or more services that expect a byte array. The payload doesn't need to be checked. Just sent over.

在本例中，它接收入站作业(job)并将其发送到Google PubSub.这可能是另一项服务-这真的无关紧要.I'm trying to find the most efficient way to convert the object to a byte array without first decoding it.个

为什么？在一台服务器上解码并转换为JSON似乎有点浪费，只是在以后将其解组.另外，我不想在两个包中维护两个相同的 struct .

如何转换io.ReadCloser接近字节数组，所以我只需要解组一次.我try 过这样的答案，但也不认为这是最有效的方法:

From io.Reader to string in Go

My http server code looks like this:

func Collect(d DbManager) http.HandlerFunc {
    return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
    w.Header().Set("Content-Type", "application/json; charset=utf-8")

    code := 422
    obj := Report{}
    response := Response{}
    response.Message = "Invalid request"

    decoder := json.NewDecoder(r.Body)
    decoder.Decode(&obj)

    if obj.Device.MachineType != "" {
        msg,_ := json.Marshal(obj)
        if d.Publish(msg, *Topic) {
          code = 200
        }
        response.Message = "Ok"
    }

    a, _ := json.Marshal(response)
    w.WriteHeader(code)
    w.Write(a)
    return
})
}