| 1 | // From JSON (encoded string values!) to "arg1=...&arg2=..." |
| 2 | function toQueryString(data) |
| 3 | { |
| 4 | let data_str = ""; |
| 5 | Object.keys(data).forEach(k => { |
| 6 | data_str += k + "=" + data[k] + "&"; |
| 7 | }); |
| 8 | return data_str.slice(0, -1); //remove last "&" |
| 9 | } |
| 10 | |
| 11 | // data, error: optional |
| 12 | function ajax(url, method, data, success, error) |
| 13 | { |
| 14 | let xhr = new XMLHttpRequest(); |
| 15 | if (typeof(data) === "function") //no data |
| 16 | { |
| 17 | error = success; |
| 18 | success = data; |
| 19 | data = {}; |
| 20 | } |
| 21 | if (!error) |
| 22 | error = errmsg => { alert(errmsg); }; |
| 23 | |
| 24 | xhr.onreadystatechange = function() { |
| 25 | if (this.readyState == 4 && this.status == 200) |
| 26 | { |
| 27 | try { |
| 28 | let res_json = JSON.parse(xhr.responseText); |
| 29 | if (!res_json.errmsg) |
| 30 | success(res_json); |
| 31 | else |
| 32 | error(res_json.errmsg); |
| 33 | } catch (e) { |
| 34 | // Plain text (e.g. for rules retrieval) |
| 35 | success(xhr.responseText); |
| 36 | } |
| 37 | } |
| 38 | }; |
| 39 | |
| 40 | if (["GET","DELETE"].includes(method) && !!data) |
| 41 | { |
| 42 | // Append query params to URL |
| 43 | url += "/?" + toQueryString(data); |
| 44 | } |
| 45 | |
| 46 | xhr.open(method, url, true); |
| 47 | xhr.setRequestHeader('X-Requested-With', "XMLHttpRequest"); |
| 48 | if (["POST","PUT"].includes(method)) |
| 49 | { |
| 50 | xhr.setRequestHeader("Content-Type", "application/json;charset=UTF-8"); |
| 51 | xhr.send(JSON.stringify(data)); |
| 52 | } |
| 53 | else |
| 54 | xhr.send(); |
| 55 | } |