Add callAPI() function

www/js/api.js

@@ -0,0 +1,47 @@
+/*
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+/**
+ * Call an API function on the server.
+ * @param {string} action
+ * @param {array} data key: value array of arguments for the server.
+ * @param {function} success Called with the JSON response object.
+ * @param {function} failure Called with an error message string.
+ * @return {undefined}
+ */
+function callAPI(action, data, success, failure) {
+    return $.ajax({
+        type: 'POST',
+        dataType: 'json',
+        url: SETTINGS["server"] + "/" + action,
+        data: data,
+        timeout: 5000,
+        success: function (data, textStatus) {
+            if (data.status === "OK") {
+                success(data);
+            } else if (data.status === "ERROR") {
+                failure(data.msg);
+            } else {
+                failure("The server sent an invalid response.");
+            }
+        },
+        error: function (xhr, textStatus, errorThrown) {
+            switch (textStatus) {
+                case "timeout":
+                    failure("Couldn't connect to the server (timeout).");
+                    break;
+                case "error":
+                    failure("Couldn't connect to the server (error).");
+                    break;
+                case "parseerror":
+                    failure("The server sent a malformed response.");
+                    break;
+                default:
+                    failure("Couldn't connect to the server.");
+            }
+        }
+    });
+}