https://rooms.xyz/js-common/xhr.js

1function doXhr(method, url, body, contentType, authToken = null) {
2  return new Promise((resolve, reject) => {
3    const x = new XMLHttpRequest();
4    x.onreadystatechange = () => {
5      if (x.readyState !== 4) return;
6      if (x.status < 200 || x.status > 299) {
7        const errorMessage = getResponseFromXHR(x, "Request failed");
8        console.warn("XHR failed with status " + x.status + ", response " + errorMessage);
9        // NOTE: clients might parse '[HTTP ...]' part from the reject result,
10        // so please preserve that!
11        reject(`[HTTP ${x.status}]: ${errorMessage}`);
12        return;
13      }
14      resolve(x.response);
15    };
16    x.responseType = "arraybuffer";
17    x.open(method, url);
18    if (authToken) x.setRequestHeader("Authorization", "Bearer " + authToken);
19    if (contentType) {
20      x.setRequestHeader("Content-Type", contentType);
21    }
22    
23    if (body) x.send(body);
24    else x.send();
25  });
26}
27
28export function xhrGet(url, authToken = null) {
29  return doXhr("GET", url, null, null, authToken);
30}
31
32export function xhrPost(url, body, contentType, authToken = null) {
33  return doXhr("POST", url, body, contentType, authToken);
34}
35
36function getResponseFromXHR(xhrObj, defaultIfError = "(error reading response)") {
37  try {

38    if (!xhrObj || !xhrObj.response || !(xhrObj.response instanceof ArrayBuffer)) return defaultIfError;
39    return (new TextDecoder('utf-8')).decode(xhrObj.response);
40  } catch (e) {
41    return defaultIfError
42  }
43}