MDL-49163 Webservices, AJAX: Add support for a new ajax webservice handler.

This is a new script that can call any function in the built-in AJAX webservice. This is a new system service that is added at install time (like the mobile webservice). It has no protocols added to it, but it accessible by a new ajax script /lib/ajax/service.php. Requests and responses to the script are required to be in json format, and multiple functions can be called in a single request.
2025-07-19 05:11:33 +02:00 · 2015-02-22 14:56:50 +08:00
parent ce1be0e738
commit 72f8324ec5
9 changed files with 305 additions and 0 deletions
--- a/lib/amd/src/ajax.js
+++ b/lib/amd/src/ajax.js
@@ -0,0 +1,139 @@
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Standard Ajax wrapper for Moodle. It calls the central Ajax script,
+ * which can call any existing webservice using the current session.
+ * In addition, it can batch multiple requests and return multiple responses.
+ *
+ * @module     core/ajax
+ * @package    core
+ * @copyright  2015 Damyon Wiese <damyon@moodle.com>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+define(['jquery', 'core/config'], function($, config) {
+
+    /**
+     * Success handler. Called when the ajax call succeeds. Checks each response and
+     * resolves or rejects the deferred from that request.
+     *
+     * @param {Object[]} responses Array of responses containing error, exception and data attributes.
+     */
+    var requestSuccess = function(responses) {
+        // Call each of the success handlers.
+        var requests = this;
+        var exception = null;
+        var i = 0;
+        var request;
+        var response;
+
+        for (i = 0; i < requests.length; i++) {
+            request = requests[i];
+
+            response = responses[i];
+            // We may not have responses for all the requests.
+            if (typeof response !== "undefined") {
+                if (response.error === false) {
+                    // Call the done handler if it was provided.
+                    request.deferred.resolve(response.data);
+                } else {
+                    exception = response.exception;
+                    break;
+                }
+            } else {
+                // This is not an expected case.
+                exception = new Error('missing response');
+                break;
+            }
+        }
+        // Something failed, reject the remaining promises.
+        if (exception !== null) {
+            for (; i < requests.length; i++) {
+                request = requests[i];
+                request.deferred.reject(exception);
+            }
+        }
+    };
+
+    /**
+     * Fail handler. Called when the ajax call fails. Rejects all deferreds.
+     *
+     * @param {jqXHR} jqXHR The ajax object.
+     * @param {string} textStatus The status string.
+     */
+    var requestFail = function(jqXHR, textStatus) {
+        // Reject all the promises.
+        var requests = this;
+
+        var i = 0;
+        for (i = 0; i < requests.length; i++) {
+            var request = requests[i];
+
+            if (typeof request.fail != "undefined") {
+                request.deferred.reject(textStatus);
+            }
+        }
+    };
+
+    return /** @alias module:core/ajax */ {
+        // Public variables and functions.
+        /**
+         * Make a series of ajax requests and return all the responses.
+         * @param {Object[]} Array of requests with each containing methodname and args properties.
+         *                   done and fail callbacks can be set for each element in the array, or the
+         *                   can be attached to the promises returned by this function.
+         * @return {Promise{}} Array of promises that will be resolved when the ajax call returns.
+         */
+        call: function(requests) {
+            var ajaxRequestData = [],
+                i,
+                promises = [];
+            for (i = 0; i < requests.length; i++) {
+                var request = requests[i];
+                ajaxRequestData.push({
+                    index: i,
+                    methodname: request.methodname,
+                    args: request.args
+                });
+                request.deferred = $.Deferred();
+                promises.push(request.deferred.promise());
+                // Allow setting done and fail handlers as arguments.
+                // This is just a shortcut for the calling code.
+                if (typeof request.done !== "undefined") {
+                    request.deferred.done(request.done);
+                }
+                if (typeof request.fail !== "undefined") {
+                    request.deferred.fail(request.fail);
+                }
+                request.index = i;
+            }
+
+            ajaxRequestData = JSON.stringify(ajaxRequestData);
+            var settings = {
+                type: 'POST',
+                data: ajaxRequestData,
+                context: requests,
+                dataType: 'json',
+                processData: false
+            };
+
+            $.ajax(config.wwwroot + '/lib/ajax/service.php', settings)
+                .done(requestSuccess)
+                .fail(requestFail);
+
+            return promises;
+        }
+    };
+});