[Golang] Get XML data from remote post (WeChat public platform)

This is a created article in which the information may have evolved or changed. Today the test uses the Go language to link the public platform, everything goes well, but the XML data sent is never received.
All the possible functions and values have been tested, such as request.form,request.postform,request.multipartform ...
Finally found that it was hidden in the request.body inside, the package of the explanation is not perfect to kill people.
The data in the request.body is IO data, which can be read out using the Ioutil.readall method.
After reading it, use the string method to transform it, and then parse it into an XML class with the corresponding parse function.
Record it and take a souvenir.