change egw.jsonq() and egw.link_title() to return promises

* egw.jsonq() now always returns a promise like egw.request(), still supporting old callback syntax
* egw.link_title(_app, _id, _callback, _context, _force_reload) supports boolean values for _callback (to not break existing code)
- false: just a cache lookup (like current call with just 2 parameters), returning null, if no title is cached, or the title
- true: always return a promise, which might already be resolved, if title was cached
- function: also returns a promise and calls the callback
--> calling egw.link_title(_app, _id) without 3rd parameter is deprecated now (gives a console.trace), to be changed in future to always return a promise, unless called with false, to just return a cache-lookup
* Et2SelectAccountReadonly and et2_link_widget is changed to use the new/updated syntax with promises

api/js/etemplate/Et2Select/Et2SelectReadonly.ts

@@ -225,18 +225,18 @@ export class Et2SelectAccountReadonly extends Et2SelectReadonly
 			let account_name = null;
 			let option = <SelectOption>{value: id, label: id + " ..."};
 			this.select_options = [].concat(this.select_options, option);
-			if(new_value && (account_name = this.egw().link_title('api-accounts', id)))
+			if(new_value && (account_name = this.egw().link_title('api-accounts', id, false)))
 			{
 				option.label = account_name;
 			}
 			else if(!account_name)
 			{
 				// Not already cached, need to fetch it
-				this.egw().link_title('api-accounts', id, function(title)
+				this.egw().link_title('api-accounts', id, true).then(title =>
 				{
-					this.option.label = title;
+					option.label = title;
-					this.select.requestUpdate();
+					this.requestUpdate();
-				}, {select: this, option: option});
+				});
 			}
 		}
 		super.value = new_value;

api/js/etemplate/et2_widget_dropdown_button.ts

@@ -437,6 +437,4 @@ export class et2_dropdown_button extends et2_inputWidget
 		}
 	}
 }
-et2_register_widget(et2_dropdown_button, ["dropdown_button"]);
+et2_register_widget(et2_dropdown_button, ["dropdown_button"]);
-
-

api/js/etemplate/et2_widget_link.ts

@@ -459,7 +459,7 @@ export class et2_link_to extends et2_inputWidget
 					if (typeof link.title == 'undefined')
 					{
 						// Callback to server for title
-						egw.link_title(link.app, link.id, function (title)
+						egw.link_title(link.app, link.id, true).then(title =>
 						{
 							link.title = title;
 							list_widget._add_link(link);
@@ -1074,7 +1074,7 @@ export class et2_link_entry extends et2_inputWidget
 		}
 		if (!_value.title)
 		{
-			var title = this.egw().link_title(_value.app, _value.id);
+			var title = this.egw().link_title(_value.app, _value.id, false);
 			if (title != null)
 			{
 				_value.title = title;
@@ -1082,13 +1082,13 @@ export class et2_link_entry extends et2_inputWidget
 			else
 			{
 				// Title will be fetched from server and then set
-				var title = this.egw().link_title(_value.app, _value.id, function (title)
+				var title = this.egw().link_title(_value.app, _value.id, true).then(title =>
 				{
 					this.search.removeClass("loading").val(title + "");
 					// Remove specific display and revert to CSS file
 					// show() would use inline, should be inline-block
 					this.clear.css('display', '');
-				}, this);
+				});
 				this.search.addClass("loading");
 			}
 		}
@@ -1452,7 +1452,7 @@ export class et2_link extends et2_valueWidget implements et2_IDetachedDOM
 			this.link.click(function (e)
 			{
 				// try to fetch value.title if it wasn't fetched during initiation.
-				if (!_value.title) _value.title = self.egw().link_title(_value.app, _value.id);
+				if (!_value.title) _value.title = self.egw().link_title(_value.app, _value.id, false);
 				if (!self.options.target_app)
 				{
 					self.options.target_app = _value.app;
@@ -1468,28 +1468,17 @@ export class et2_link extends et2_valueWidget implements et2_IDetachedDOM
 		}
 		if (!_value.title)
 		{
-			var self = this;
+			const node = this.link[0];
-			var node = this.link[0];
 			if (_value.app && _value.id)
 			{
-				var title = this.egw().link_title(_value.app, _value.id, function (title)
+				this.egw().link_title(_value.app, _value.id, true).then(title =>
 				{
-					self.set_title(node, title);
+					this.set_title(node, title);
-				}, this);
+				});
-				if (title != null)
+				// Title will be fetched from server and then set
-				{
+				return;
-					_value.title = title;
-				}
-				else
-				{
-					// Title will be fetched from server and then set
-					return;
-				}
-			}
-			else
-			{
-				_value.title = "";
 			}
+			_value.title = "";
 		}
 		this.set_title(this.link, _value.title);
 	}
@@ -1760,13 +1749,13 @@ export class et2_link_string extends expose(class et2_link_string extends et2_va
 		// Now that link is created, get title from server & update
 		else
 		{
-			this.egw().link_title(_link_data.app, _link_data.id, function (title)
+			this.egw().link_title(_link_data.app, _link_data.id, true).then(title =>
 			{
 				if (title)
-					this.removeClass("loading").text(title);
+					link.removeClass("loading").text(title);
 				else
-					this.remove();	// no rights or not found
+					link.remove();	// no rights or not found
-			}, link);
+			});
 		}
 	}
 
@@ -2208,10 +2197,10 @@ export class et2_link_list extends et2_link_string
 		{
 			// Title will be fetched from server and then set
 			jQuery('td.title', row).addClass("loading");
-			var title = this.egw().link_title(_link_data.app, _link_data.id, function (title)
+			this.egw().link_title(_link_data.app, _link_data.id, true).then(title =>
 			{
-				jQuery('td.title', this).removeClass("loading").text(title + "");
+				jQuery('td.title', row).removeClass("loading").text(title + "");
-			}, row);
+			});
 		}
 		// Date
 		/*
@@ -2526,4 +2515,4 @@ export class et2_link_add extends et2_inputWidget
 	}
 }
 
-et2_register_widget(et2_link_add, ["link-add"]);
+et2_register_widget(et2_link_add, ["link-add"]);

api/js/jsapi/egw_jsonq.js

@@ -7,7 +7,6 @@
  * @link http://www.egroupware.org
  * @author Andreas Stöckel (as AT stylite.de)
  * @author Ralf Becker <RalfBecker@outdoor-training.de>
- * @version $Id$
  */
 
 /*egw:uses
@@ -32,56 +31,17 @@ egw.extend('jsonq', egw.MODULE_GLOBAL, function()
 	 *
 	 * @access private, use jsonq method to queue requests
 	 */
-	var jsonq_queue = {};
+	const jsonq_queue = {};
 
 	/**
 	 * Next uid (index) in queue
 	 */
-	var jsonq_uid = 0;
+	let jsonq_uid = 0;
 
 	/**
 	 * Running timer for next send of queued items
 	 */
-	var jsonq_timer = null;
+	let jsonq_timer = null;
-
-	/**
-	 * Dispatch responses received
-	 *
-	 * @param {object} _data uid => response pairs
-	 */
-	function jsonq_callback(_data)
-	{
-		if (typeof _data != 'object') throw "jsonq_callback called with NO object as parameter!";
-
-		// Abort if type is set (multi-response support)
-		if (typeof _data.type != 'undefined') return;
-
-		var json = egw.json('none');
-		for(var uid in _data)
-		{
-			if (typeof jsonq_queue[uid] == 'undefined')
-			{
-				console.log("jsonq_callback received response for not existing queue uid="+uid+"!");
-				console.log(_data[uid]);
-				continue;
-			}
-			var job = jsonq_queue[uid];
-			var response = _data[uid];
-
-			// fake egw.json_request object, to call it with the current response
-			json.callback = job.callback;
-			json.sender = job.sender;
-			json.handleResponse({response: response});
-
-			delete jsonq_queue[uid];
-		}
-		// if nothing left in queue, stop interval-timer to give browser a rest
-		if (jsonq_timer && typeof jsonq_queue['u'+(jsonq_uid-1)] != 'object')
-		{
-			window.clearInterval(jsonq_timer);
-			jsonq_timer = null;
-		}
-	}
 
 	/**
 	 * Send the whole job-queue to the server in a single json request with menuaction=queue
@@ -90,16 +50,16 @@ egw.extend('jsonq', egw.MODULE_GLOBAL, function()
 	{
 		if (jsonq_uid > 0 && typeof jsonq_queue['u'+(jsonq_uid-1)] == 'object')
 		{
-			var jobs_to_send = {};
+			const jobs_to_send = {};
-			var something_to_send = false;
+			let something_to_send = false;
-			for(var uid in jsonq_queue)
+			for(let uid in jsonq_queue)
 			{
-				var job = jsonq_queue[uid];
+				const job = jsonq_queue[uid];
 
-				if (job.menuaction == 'send') continue;	// already send to server
+				if (job.menuaction === 'send') continue;	// already send to server
 
-				// if job has a callbeforesend callback, call it to allow it to modify pararmeters
+				// if job has a callbeforesend callback, call it to allow it to modify parameters
-				if (typeof job.callbeforesend == 'function')
+				if (typeof job.callbeforesend === 'function')
 				{
 					job.callbeforesend.call(job.sender, job.parameters);
 				}
@@ -113,8 +73,54 @@ egw.extend('jsonq', egw.MODULE_GLOBAL, function()
 			}
 			if (something_to_send)
 			{
-				var request = egw.json('api.queue', jobs_to_send, jsonq_callback, this);
+				egw.request('api.queue', jobs_to_send).then(_data =>
-				request.sendRequest(true);
+				{
+					if (typeof _data != 'object') throw "jsonq_callback called with NO object as parameter!";
+
+					const json = egw.json('none');
+					for(let uid in _data)
+					{
+						if (typeof jsonq_queue[uid] == 'undefined')
+						{
+							console.log("jsonq_callback received response for not existing queue uid="+uid+"!");
+							console.log(_data[uid]);
+							continue;
+						}
+						const job = jsonq_queue[uid];
+						const response = _data[uid];
+
+						// The ajax request has completed, get just the data & pass it on
+						if(response)
+						{
+							for(let value of response)
+							{
+								if(value.type && value.type === "data" && typeof value.data !== "undefined")
+								{
+									// Data was packed in response
+									job.resolve(value.data);
+								}
+								else if (value && typeof value.type === "undefined" && typeof value.data === "undefined")
+								{
+									// Just raw data
+									job.resolve(value);
+								}
+								else
+								{
+									// fake egw.json_request object, to call it with the current response
+									json.handleResponse({response: response});
+								}
+							}
+						}
+
+						delete jsonq_queue[uid];
+					}
+					// if nothing left in queue, stop interval-timer to give browser a rest
+					if (jsonq_timer && typeof jsonq_queue['u'+(jsonq_uid-1)] != 'object')
+					{
+						window.clearInterval(jsonq_timer);
+						jsonq_timer = null;
+					}
+				});
 			}
 		}
 	}
@@ -127,35 +133,40 @@ egw.extend('jsonq', egw.MODULE_GLOBAL, function()
 		 *   which handles the actual request. If the menuaction is a full featured
 		 *   url, this one will be used instead.
 		 * @param {array} _parameters which should be passed to the menuaction function.
-		 * @param  {function} _callback callback function which should be called upon a "data" response is received
+		 * @param {function|undefined} _callback callback function which should be called upon a "data" response is received
-		 * @param {object} _sender is the reference object the callback function should get
+		 * @param {object|undefined} _sender is the reference object the callback function should get
-		 * @param {function} _callbeforesend optional callback function which can modify the parameters, eg. to do some own queuing
+		 * @param {function|undefined} _callbeforesend optional callback function which can modify the parameters, eg. to do some own queuing
-		 * @return string uid of the queued request
+		 * @return Promise
 		 */
 		jsonq: function(_menuaction, _parameters, _callback, _sender, _callbeforesend)
 		{
-			var uid = 'u'+(jsonq_uid++);
+			const uid = 'u'+(jsonq_uid++);
 			jsonq_queue[uid] = {
 				menuaction: _menuaction,
 				// IE JSON-serializes arrays passed in from different window contextx (eg. popups)
 				// as objects (it looses object-type of array), causing them to be JSON serialized
 				// as objects and loosing parameters which are undefined
-				// JSON.strigify([123,undefined]) --> '{"0":123}' instead of '[123,null]'
+				// JSON.stringify([123,undefined]) --> '{"0":123}' instead of '[123,null]'
 				parameters: _parameters ? [].concat(_parameters) : [],
-				callback: _callback,
+				callbeforesend: _sender ? _callbeforesend.bind(_sender) : _callbeforesend,
-				sender: _sender,
-				callbeforesend: _callbeforesend
 			};
+			let promise = new Promise(resolve => {
+				jsonq_queue[uid].resolve = resolve;
+			});
+			if (typeof _callback === 'function')
+			{
+				promise = promise.then(_data => {
+					_callback.bind(_sender)(_data);
+					return _data;
+				});
+			}
 
 			if (jsonq_timer == null)
 			{
 				// check / send queue every N ms
-				var self = this;
+				jsonq_timer = window.setInterval(() => jsonq_send(), 100);
-				jsonq_timer = window.setInterval(function(){
-					jsonq_send.call(self);
-				}, 100);
 			}
-			return uid;
+			return promise;
 		},
 
 		/**
@@ -187,4 +198,4 @@ egw.extend('jsonq', egw.MODULE_GLOBAL, function()
 		}
 
 	};
-});
+});

api/js/jsapi/egw_links.js

@@ -7,7 +7,6 @@
  * @link http://www.egroupware.org
  * @author Andreas Stöckel (as AT stylite.de)
  * @author Ralf Becker <RalfBecker@outdoor-training.de>
- * @version $Id$
  */
 
 /*egw:uses
@@ -27,14 +26,14 @@ egw.extend('links', egw.MODULE_GLOBAL, function()
 	 *
 	 * @access: private, use egw.open() or egw.set_link_registry()
 	 */
-	var link_registry = undefined;
+	let link_registry = undefined;
 
 	/**
 	 * Local cache for link-titles
 	 *
 	 * @access private, use egw.link_title(_app, _id[, _callback, _context])
 	 */
-	var title_cache = {};
+	let title_cache = {};
 
 	/**
 	 * Queue for link_title requests
@@ -42,14 +41,14 @@ egw.extend('links', egw.MODULE_GLOBAL, function()
 	 * @access private, use egw.link_title(_app, _id[, _callback, _context])
 	 * @var object _app._id.[{callback: _callback, context: _context}[, ...]]
 	 */
-	var title_queue = {};
+	let title_queue = {};
 
 	/**
-	 * Uid of active jsonq request, to not start an other one, as we get notified
+	 * Uid of active jsonq request, to not start another one, as we get notified
 	 * before it's actually send to the server via our link_title_before_send callback.
 	 * @access private
 	 */
-	var title_uid = null;
+	let title_uid = null;
 
 	return {
 		/**
@@ -62,19 +61,19 @@ egw.extend('links', egw.MODULE_GLOBAL, function()
 		 */
 		link_get_registry: function(_app, _name)
 		{
-			if (typeof link_registry != 'object')
+			if (typeof link_registry !== 'object')
 			{
 				alert('egw.open() link registry is NOT defined!');
 				return false;
 			}
-			if (typeof link_registry[_app] == 'undefined')
+			if (typeof link_registry[_app] === 'undefined')
 			{
 				return false;
 			}
-			var reg = link_registry[_app];
+			const reg = link_registry[_app];
 
 			// some defaults (we set them directly in the registry, to do this only once)
-			if (typeof reg[_name] == 'undefined')
+			if (typeof reg[_name] === 'undefined')
 			{
 				switch(_name)
 				{
@@ -82,9 +81,9 @@ egw.extend('links', egw.MODULE_GLOBAL, function()
 						reg.name = _app;
 						break;
 					case 'icon':
-						var app_data = this.app(_app);
+						const app_data = this.app(_app);
-						if (typeof app_data != 'undefined' &&
+						if (typeof app_data !== 'undefined' &&
-							typeof app_data.icon != 'undefined' && app_data.icon != null)
+							typeof app_data.icon !== 'undefined' && app_data.icon !== null)
 						{
 							reg.icon = (typeof app_data.icon_app != 'undefined' ? app_data.icon_app : _app)+'/'+app_data.icon;
 						}
@@ -95,12 +94,12 @@ egw.extend('links', egw.MODULE_GLOBAL, function()
 						break;
 				}
 			}
-			if (reg && typeof _name == 'undefined')
+			if (reg && typeof _name === 'undefined')
 			{
 				// No key requested, return the whole thing
 				return reg;
 			}
-			return typeof reg[_name] == 'undefined' ? false : reg[_name];
+			return typeof reg[_name] === 'undefined' ? false : reg[_name];
 		},
 
 		/**
@@ -113,16 +112,16 @@ egw.extend('links', egw.MODULE_GLOBAL, function()
 		 */
 		get_mime_info: function(_type)
 		{
-			var wildcard_mime;
+			let wildcard_mime;
 			for(var app in link_registry)
 			{
-				var reg = link_registry[app];
+				const reg = link_registry[app];
-				if (typeof reg.mime != 'undefined')
+				if (typeof reg.mime !== 'undefined')
 				{
-					for(var mime in reg.mime)
+					for(let mime in reg.mime)
 					{
-						if (mime == _type) return reg.mime[_type];
+						if (mime === _type) return reg.mime[_type];
-						if (mime[0] == '/' && _type.match(new RegExp(mime.substring(1, mime.length-1), 'i')))
+						if (mime[0] === '/' && _type.match(new RegExp(mime.substring(1, mime.length-1), 'i')))
 						{
 							wildcard_mime = reg.mime[mime];
 						}
@@ -142,10 +141,10 @@ egw.extend('links', egw.MODULE_GLOBAL, function()
 		 */
 		mime_open: function(_path, _type)
 		{
-			var path;
+			let path;
-			if (typeof _path == 'object')
+			if (typeof _path === 'object')
 			{
-				if (typeof _path.path == 'undefined')
+				if (typeof _path.path === 'undefined')
 				{
 					path = '/apps/'+_path.app2+'/'+_path.id2+'/'+_path.id;
 				}
@@ -153,12 +152,12 @@ egw.extend('links', egw.MODULE_GLOBAL, function()
 				{
 					path = _path.path;
 				}
-				if (typeof _path.type == 'string')
+				if (typeof _path.type === 'string')
 				{
 					_type = _path.type;
 				}
 			}
-			else if(_path[0] != '/')
+			else if(_path[0] !== '/')
 			{
 
 			}
@@ -166,11 +165,11 @@ egw.extend('links', egw.MODULE_GLOBAL, function()
 			{
 				path = _path;
 			}
-			var mime_info = this.get_mime_info(_type);
+			let mime_info = this.get_mime_info(_type);
+			let data = {};
 			if (mime_info)
 			{
-				var data = {};
+				for(let attr in mime_info)
-				for(var attr in mime_info)
 				{
 					switch(attr)
 					{
@@ -190,14 +189,14 @@ egw.extend('links', egw.MODULE_GLOBAL, function()
 					}
 				}
 				// if mime_info did NOT define mime_url attribute, we use a WebDAV url drived from path
-				if (typeof mime_info.mime_url == 'undefined')
+				if (typeof mime_info.mime_url === 'undefined')
 				{
-					data.url = typeof _path == 'object' && _path.download_url ? _path.download_url : '/webdav.php' + path;
+					data.url = typeof _path === 'object' && _path.download_url ? _path.download_url : '/webdav.php' + path;
 				}
 			}
 			else
 			{
-				var data = typeof _path == 'object' && _path.download_url ? _path.download_url : '/webdav.php' + path;
+				data = typeof _path === 'object' && _path.download_url ? _path.download_url : '/webdav.php' + path;
 			}
 			return data;
 		},
@@ -210,28 +209,29 @@ egw.extend('links', egw.MODULE_GLOBAL, function()
 		 */
 		link_app_list: function(_must_support)
 		{
-			var apps = [];
+			let apps = [];
-			for (var type in link_registry)
+			for (let type in link_registry)
 			{
-				var reg = link_registry[type];
+				const reg = link_registry[type];
 
-				if (typeof _must_support != 'undefined' && _must_support && typeof reg[_must_support] == 'undefined') continue;
+				if (typeof _must_support !== 'undefined' && _must_support && typeof reg[_must_support] === 'undefined') continue;
 
-				var app_sub = type.split('-');
+				const app_sub = type.split('-');
 				if (this.app(app_sub[0]))
 				{
 					apps.push({"type": type, "label": this.lang(this.link_get_registry(type,'name'))});
 				}
 			}
-			// sort labels (caseinsensitive) alphabetic
+			// sort labels (case-insensitive) alphabetic
-			apps = apps.sort(function(_a,_b) {
+			apps = apps.sort((_a, _b) =>
+			{
 				var al = _a.label.toUpperCase();
 				var bl = _b.label.toUpperCase();
-				return al == bl ? 0 : (al > bl ? 1 : -1);
+				return al === bl ? 0 : (al > bl ? 1 : -1);
 			});
 			// create sorted associative array / object
-			var sorted = {};
+			const sorted = {};
-			for(var i = 0; i < apps.length; ++i)
+			for(let i = 0; i < apps.length; ++i)
 			{
 				sorted[apps[i].type] = apps[i].label;
 			}
@@ -248,7 +248,7 @@ egw.extend('links', egw.MODULE_GLOBAL, function()
 		 */
 		set_link_registry: function (_registry, _app, _need_clone)
 		{
-			if (typeof _app == 'undefined')
+			if (typeof _app === 'undefined')
 			{
 				link_registry = _need_clone ? jQuery.extend(true, {}, _registry) : _registry;
 			}
@@ -271,7 +271,7 @@ egw.extend('links', egw.MODULE_GLOBAL, function()
 		 */
 		link: function(_url, _extravars)
 		{
-			if (_url.substr(0,4) == 'http' && _url.indexOf('://') <= 5)
+			if (_url.substr(0,4) === 'http' && _url.indexOf('://') <= 5)
 			{
 				// already a full url (eg. download_url of vfs), nothing to do
 			}
@@ -280,7 +280,7 @@ egw.extend('links', egw.MODULE_GLOBAL, function()
 				if (_url[0] != '/')
 				{
 					alert("egw.link('"+_url+"') called with url starting NOT with a slash!");
-					var app = window.egw_appName;
+					const app = window.egw_appName;
 					if (app != 'login' && app != 'logout') _url = app+'/'+_url;
 				}
 				// append the url to the webserver url, if not already contained or empty
@@ -289,12 +289,12 @@ egw.extend('links', egw.MODULE_GLOBAL, function()
 					_url = this.webserverUrl + _url;
 				}
 			}
-			var vars = {};
+			const vars = {};
 
 			// check if the url already contains a query and ensure that vars is an array and all strings are in extravars
-			var url_othervars = _url.split('?',2);
+			const url_othervars = _url.split('?',2);
 			_url = url_othervars[0];
-			var othervars = url_othervars[1];
+			const othervars = url_othervars[1];
 			if (_extravars && typeof _extravars == 'object')
 			{
 				jQuery.extend(vars, _extravars);
@@ -310,16 +310,16 @@ egw.extend('links', egw.MODULE_GLOBAL, function()
 			if (_extravars)
 			{
 				_extravars = _extravars.split('&');
-				for(var i=0; i < _extravars.length; ++i)
+				for(let i=0; i < _extravars.length; ++i)
 				{
-					var name_val = _extravars[i].split('=',2);
+					const name_val = _extravars[i].split('=', 2);
-					var name = name_val[0];
+					let name = name_val[0];
-					var val = name_val[1] || '';
+					let val = name_val[1] || '';
-					if (val.indexOf('%26') != -1) val = val.replace(/%26/g,'&');	// make sure to not double encode &
+					if (val.indexOf('%26') !== -1) val = val.replace(/%26/g,'&');	// make sure to not double encode &
 					if (name.lastIndexOf('[]') == name.length-2)
 					{
 						name = name.substr(0,name.length-2);
-						if (typeof vars[name] == 'undefined') vars[name] = [];
+						if (typeof vars[name] === 'undefined') vars[name] = [];
 						vars[name].push(val);
 					}
 					else
@@ -330,14 +330,14 @@ egw.extend('links', egw.MODULE_GLOBAL, function()
 			}
 
 			// if there are vars, we add them urlencoded to the url
-			var query = [];
+			let query = [];
 
-			for(var name in vars)
+			for(let name in vars)
 			{
-				var val = vars[name] || '';	// fix error for eg. null, which is an object!
+				let val = vars[name] || '';	// fix error for eg. null, which is an object!
 				if (typeof val == 'object')
 				{
-					for(var i=0; i < val.length; ++i)
+					for(let i=0; i < val.length; ++i)
 					{
 						query.push(name+'[]='+encodeURIComponent(val[i]));
 					}
@@ -354,44 +354,66 @@ egw.extend('links', egw.MODULE_GLOBAL, function()
 		/**
 		 * Query a title of _app/_id
 		 *
+		 * Deprecated default of returning string or null for no callback, will change in future to always return a Promise!
+		 *
 		 * @param {string} _app
 		 * @param {string|number} _id
-		 * @param {function} _callback optinal callback, required if for responses from the server
+		 * @param {boolean|function|undefined} _callback true to always return a promise, false: just lookup title-cache or optional callback
-		 * @param {object} _context context for the callback
+		 * 	NOT giving either a boolean value or a callback is deprecated!
+		 * @param {object|undefined} _context context for the callback
 		 * @param {boolean} _force_reload true load again from server, even if already cached
-		 * @return {string|boolean|null} string with title if it exist in local cache or null if not
+		 * @return {Promise|string|null} Promise for _callback given (function or true), string with title if it exists in local cache or null if not
 		 */
 		link_title: function(_app, _id, _callback, _context, _force_reload)
 		{
 			// check if we have a cached title --> return it direct
-			if (typeof title_cache[_app] != 'undefined' && typeof title_cache[_app][_id] != 'undefined' && _force_reload !== true)
+			if (typeof title_cache[_app] !== 'undefined' && typeof title_cache[_app][_id] !== 'undefined' && _force_reload !== true)
 			{
-				if (typeof _callback == 'function')
+				if (typeof _callback === 'function')
 				{
 					_callback.call(_context, title_cache[_app][_id]);
 				}
+				if (_callback)
+				{
+					return Promise.resolve(title_cache[_app][_id]);
+				}
 				return title_cache[_app][_id];
 			}
 			// no callback --> return null
-			if (typeof _callback != 'function')
+			if (!_callback)
 			{
-				return null;	// not found in local cache and cant do a synchronious request
+				if (_callback !== false)
+				{
+					console.trace('Deprecated use of egw.link() without 3rd parameter callback!');
+				}
+				return null;	// not found in local cache and can't do a synchronous request
 			}
 			// queue the request
-			if (typeof title_queue[_app] == 'undefined')
+			if (typeof title_queue[_app] === 'undefined')
 			{
 				title_queue[_app] = {};
 			}
-			if (typeof title_queue[_app][_id] == 'undefined')
+			if (typeof title_queue[_app][_id] === 'undefined')
 			{
 				title_queue[_app][_id] = [];
 			}
-			title_queue[_app][_id].push({callback: _callback, context: _context});
+			let promise = new Promise(_resolve => {
-			// if there's no active jsonq request, start a new one
+				title_queue[_app][_id].push({callback: _resolve, context: _context});
-			if (title_uid == null)
+			});
+			if (typeof _callback === 'function')
 			{
-				title_uid = this.jsonq('EGroupware\\Api\\Etemplate\\Widget\\Link::ajax_link_titles',[{}], this.link_title_callback, this, this.link_title_before_send);
+				promise = promise.then(_data => {
+					_callback.bind(_context)(_data);
+					return _data;
+				});
 			}
+			// if there's no active jsonq request, start a new one
+			if (title_uid === null)
+			{
+				title_uid = this.jsonq('EGroupware\\Api\\Etemplate\\Widget\\Link::ajax_link_titles',[{}], undefined, this, this.link_title_before_send)
+					.then(_response => this.link_title_callback(_response));
+			}
+			return promise;
 		},
 
 		/**
@@ -402,11 +424,11 @@ egw.extend('links', egw.MODULE_GLOBAL, function()
 		link_title_before_send: function(_params)
 		{
 			// add all current title-requests
-			for(var app in title_queue)
+			for(let app in title_queue)
 			{
-				for(var id in title_queue[app])
+				for(let id in title_queue[app])
 				{
-					if (typeof _params[0][app] == 'undefined')
+					if (typeof _params[0][app] === 'undefined')
 					{
 						_params[0][app] = [];
 					}
@@ -423,29 +445,27 @@ egw.extend('links', egw.MODULE_GLOBAL, function()
 		 */
 		link_title_callback: function(_response)
 		{
-			if (typeof _response != 'object')
+			if (typeof _response !== 'object')
 			{
 				throw "Wrong parameter for egw.link_title_callback!";
 			}
-			for(var app in _response)
+			for(let app in _response)
 			{
-				if (typeof title_cache[app] != 'object')
+				if (typeof title_cache[app] !== 'object')
 				{
 					title_cache[app] = {};
 				}
-				for (var id in _response[app])
+				for (let id in _response[app])
 				{
-					var title = _response[app][id];
+					const title = _response[app][id];
 					// cache locally
 					title_cache[app][id] = title;
 					// call callbacks waiting for title of app/id
-					if(typeof title_queue[app] !== 'undefined' &&
+					if (typeof title_queue[app] !== 'undefined' && typeof title_queue[app][id] !== "undefined")
-						typeof title_queue[app][id] !== "undefined"
-					)
 					{
-						for(var i=0; i < title_queue[app][id].length; ++i)
+						for(let i=0; i < title_queue[app][id].length; ++i)
 						{
-							var callback = title_queue[app][id][i];
+							const callback = title_queue[app][id][i];
 							callback.callback.call(callback.context, title);
 						}
 						delete title_queue[app][id];
@@ -464,10 +484,10 @@ egw.extend('links', egw.MODULE_GLOBAL, function()
 			// check if quick-add selectbox is alread there, only create it again if not
 			if (document.getElementById('quick_add_selectbox')) return;
 
-			var select = jQuery(document.createElement('select')).attr('id', 'quick_add_selectbox');
+			const select = jQuery(document.createElement('select')).attr('id', 'quick_add_selectbox');
-			jQuery(typeof _parent == 'string' ? '#'+_parent : _parent).append(select);
+			jQuery(typeof _parent === 'string' ? '#'+_parent : _parent).append(select);
 
-			var self = this;
+			const self = this;
 			// bind change handler
 			select.change(function(){
 				if (this.value) self.open('', this.value, 'add', {}, undefined, this.value, true);
@@ -476,18 +496,18 @@ egw.extend('links', egw.MODULE_GLOBAL, function()
 			// need to load common translations for app-names
 			this.langRequire(window, [{app: 'common', lang: this.preference('lang')}], function(){
 				select.append(jQuery(document.createElement('option')).attr('value', '').text(self.lang('Add')+' ...'));
-				var apps = self.link_app_list('add');
+				const apps = self.link_app_list('add');
-				for(var app in apps)
+				for(let app in apps)
 				{
 					if(egw.link_get_registry(app, 'no_quick_add'))
 					{
 						continue;
 					}
-					var option = jQuery(document.createElement('option')).attr('value', app)
+					const option = jQuery(document.createElement('option')).attr('value', app)
 						.text(self.lang(self.link_get_registry(app,'entry') || apps[app]));
 					select.append(option);
 				}
 			});
 		}
 	};
-});
+});