[Qt-qml] A simple javascript Rest http Requst(Get-Post-Put-Delete)

Http.js

var Request = function (options) {
    var http = {
        "xhr": new XMLHttpRequest(),
        "URLbase": '',
        "method": 'GET',
        "userAgent": null,
        "success": null,
        "fail": null,
        "callback": function () {
            if (http.xhr.readyState !== 4) {
                return
            }
            if (http.xhr.status === 200 && http.success) {
                http.success(JSON.parse(http.xhr.responseText))
            } else if (http.fail) {
                http.fail(http.xhr.status, http.xhr.responseText)
            }
        },
        "setHeaders": function (headers) {
            for (var hkey in headers) {
                if (headers.hasOwnProperty(hkey)) {
                    this.xhr.setRequestHeader(hkey, headers[hkey])
                }
            }
        },
        "request": function (uri, async, user, password) {
            this.xhr.open(uri.method, uri.url, async, user, password)
            this.xhr.onreadystatechange = this.callback
            if (uri.headers) {
                this.setHeaders(uri.headers)
            }

            var methods = ['GET', 'COPY', 'HEAD', 'OPTIONS', 'PURGE']
            if (methods.indexOf(uri.method) > -1) {
                this.xhr.send(null)
            } else {
                this.xhr.send(uri.data)
            }
        },
        "then": function (callback) {
            if (this.xhr.readyState === 4) {
                callback(JSON.parse(this.xhr.responseText))
            } else {
                this.success = callback
            }
            return this
        },
        "catch": function (callback) {
            if (this.xhr.readyState === 4) {
                callback(this.xhr.status, this.xhr.responseText)
            } else {
                this.fail = callback
            }
            return this
        },
        "get": function (url) {
            this.request({
                             "method": 'GET',
                             "url": this.URLbase + url
                         }, true)
            return this
        },
        "post": function (url, data) {
            this.request({
                             "method": 'POST',
                             "headers": {
                                 "Content-type": 'application/json'
                             },
                             "url": this.URLbase + url,
                             "data": JSON.stringify(data)
                         }, true)
            return this
        },
        "put": function (url, data) {
            this.request({
                             "method": 'PUT',
                             "headers": {
                                 "Content-type": 'application/json'
                             },
                             "url": this.URLbase + url,
                             "data": JSON.stringify(data)
                         }, true)
            return this
        },
        "del": function (url, data) {
            if (typeof data !== 'object') {
                data = {
                    "id": data
                }
            }
            this.request({
                             "method": 'DELETE',
                             "headers": {
                                 "Content-type": 'application/json'
                             },
                             "url": this.URLbase + url,
                             "data": JSON.stringify(data)
                         }, true)
            return this
        }
    }
    for (var op in options) {
        http[op] = options[op]
    }
    return http
}
/* Simple example
        var connection = new Rest.Request({
                                              "URLbase": 'http://127.0.0.1/api/'
                                          })
        connection.put('Table', {
                           "id": 12,
                           "name": "name",
                           "date": "now"
                       }).then(function (JsonObject) {
                           textFilde1.text = JsonObject.stat
                       }).catch(function (err) {
                           console.log(err)
                       })
*/