Golang无法从request.GetBody（）获取正文

Question

I try to read the request body via request.GetBody(), since I need to read the same request body more than once, but I always get the error below. I checked if the req.body is empty, but it is not. I cant even call req.GetBody(). My Go version is 1.8.1.

 func read(res http.ResponseWriter, req *http.Request) {

     _, err := req.GetBody()
    if err != nil {
        res.Write([]byte(err.Error()))
        return
    }

}

Error:

http: panic serving [::1]:53174: runtime error: invalid memory address or nil pointer dereference

Answer 1

The GetBody() func on Request is only for client requests (see the documentation over the GetBody member: https://golang.org/pkg/net/http/#Request), but it looks like you're doing a server-side handler. Therefore, you need to use the req.Body member, which is an io.ReadCloser. To read from an io.ReadCloser you can use the io/ioutil package and the ReadAll() func:

b, err := ioutil.ReadAll(req.Body)
if err != nil {
    panic(err)
}

fmt.Printf("%s", b)

More information on the ReadAll() func: https://golang.org/pkg/io/ioutil/#example_ReadAll