How To Make A Json Object Out Of Getallresponseheaders Method

I am currently writing a google chrome extension, and I need to find out information about websites' response headers. In order to do this, I used the getAllResponseHeaders method,

Solution 1:

See https://msdn.microsoft.com/en-us/library/ms536428(v=vs.85).aspx. The return headers are a crlf delimited string where each line contains key values separated by a colon. You will probably have to adjust the code below to account for whitespace.

var arr = allResponseHeaders.split('\r\n');
var headers = arr.reduce(function (acc, current, i){
      var parts = current.split(': ');
      acc[parts[0]] = parts[1];
      return acc;
}, {});

Solution 2:

I use the following function to extract all response headers as JS object using getAllResponseHeaders():

functiongetResponseHeaderMap(xhr) {
  const headers = {};
  xhr.getAllResponseHeaders()
      .trim()
      .split(/[\r\n]+/)
      .map(value => value.split(/: /))
      .forEach(keyValue => {
        headers[keyValue[0].trim()] = keyValue[1].trim();
      });
  return headers;
}

Solution 3:

You should put JSON.parse logic inside the callback onreadystatechange, since Ajax is an asynchronous call and allResponseHeaders may not be initialized when you use it right after sending the http request.