JSDoc: Source: luci.js

/**
- * @class LuCI
- * @classdesc
- *
- * This is the LuCI base class. It is automatically instantiated and
- * accessible using the global `L` variable.
- *
- * @param {Object} env
- * The environment settings to use for the LuCI runtime.
- */
-
-(function(window, document, undefined) {
-	'use strict';
-
-	/* Object.assign polyfill for IE */
-	if (typeof Object.assign !== 'function') {
-		Object.defineProperty(Object, 'assign', {
-			value: function assign(target, varArgs) {
-				if (target == null)
-					throw new TypeError('Cannot convert undefined or null to object');
-
-				var to = Object(target);
-
-				for (var index = 1; index < arguments.length; index++)
-					if (arguments[index] != null)
-						for (var nextKey in arguments[index])
-							if (Object.prototype.hasOwnProperty.call(arguments[index], nextKey))
-								to[nextKey] = arguments[index][nextKey];
-
-				return to;
-			},
-			writable: true,
-			configurable: true
-		});
-	}
-
-	/* Promise.finally polyfill */
-	if (typeof Promise.prototype.finally !== 'function') {
-		Promise.prototype.finally = function(fn) {
-			var onFinally = function(cb) {
-				return Promise.resolve(fn.call(this)).then(cb);
-			};
-
-			return this.then(
-				function(result) { return onFinally.call(this, function() { return result }) },
-				function(reason) { return onFinally.call(this, function() { return Promise.reject(reason) }) }
-			);
-		};
-	}
-
-	/*
-	 * Class declaration and inheritance helper
-	 */
-
-	var toCamelCase = function(s) {
-		return s.replace(/(?:^|[\. -])(.)/g, function(m0, m1) { return m1.toUpperCase() });
-	};
-
-	/**
-	 * @class Class
-	 * @hideconstructor
-	 * @memberof LuCI
-	 * @classdesc
-	 *
-	 * `LuCI.Class` is the abstract base class all LuCI classes inherit from.
-	 *
-	 * It provides simple means to create subclasses of given classes and
-	 * implements prototypal inheritance.
-	 */
-	var superContext = null, Class = Object.assign(function() {}, {
-		/**
-		 * Extends this base class with the properties described in
-		 * `properties` and returns a new subclassed Class instance
-		 *
-		 * @memberof LuCI.Class
-		 *
-		 * @param {Object<string, *>} properties
-		 * An object describing the properties to add to the new
-		 * subclass.
-		 *
-		 * @returns {LuCI.Class}
-		 * Returns a new LuCI.Class sublassed from this class, extended
-		 * by the given properties and with its prototype set to this base
-		 * class to enable inheritance. The resulting value represents a
-		 * class constructor and can be instantiated with `new`.
-		 */
-		extend: function(properties) {
-			var props = {
-				__base__: { value: this.prototype },
-				__name__: { value: properties.__name__ || 'anonymous' }
-			};
-
-			var ClassConstructor = function() {
-				if (!(this instanceof ClassConstructor))
-					throw new TypeError('Constructor must not be called without "new"');
-
-				if (Object.getPrototypeOf(this).hasOwnProperty('__init__')) {
-					if (typeof(this.__init__) != 'function')
-						throw new TypeError('Class __init__ member is not a function');
-
-					this.__init__.apply(this, arguments)
-				}
-				else {
-					this.super('__init__', arguments);
-				}
-			};
-
-			for (var key in properties)
-				if (!props[key] && properties.hasOwnProperty(key))
-					props[key] = { value: properties[key], writable: true };
-
-			ClassConstructor.prototype = Object.create(this.prototype, props);
-			ClassConstructor.prototype.constructor = ClassConstructor;
-			Object.assign(ClassConstructor, this);
-			ClassConstructor.displayName = toCamelCase(props.__name__.value + 'Class');
-
-			return ClassConstructor;
-		},
-
-		/**
-		 * Extends this base class with the properties described in
-		 * `properties`, instantiates the resulting subclass using
-		 * the additional optional arguments passed to this function
-		 * and returns the resulting subclassed Class instance.
-		 *
-		 * This function serves as a convenience shortcut for
-		 * {@link LuCI.Class.extend Class.extend()} and subsequent
-		 * `new`.
-		 *
-		 * @memberof LuCI.Class
-		 *
-		 * @param {Object<string, *>} properties
-		 * An object describing the properties to add to the new
-		 * subclass.
-		 *
-		 * @param {...*} [new_args]
-		 * Specifies arguments to be passed to the subclass constructor
-		 * as-is in order to instantiate the new subclass.
-		 *
-		 * @returns {LuCI.Class}
-		 * Returns a new LuCI.Class instance extended by the given
-		 * properties with its prototype set to this base class to
-		 * enable inheritance.
-		 */
-		singleton: function(properties /*, ... */) {
-			return Class.extend(properties)
-				.instantiate(Class.prototype.varargs(arguments, 1));
-		},
-
-		/**
-		 * Calls the class constructor using `new` with the given argument
-		 * array being passed as variadic parameters to the constructor.
-		 *
-		 * @memberof LuCI.Class
-		 *
-		 * @param {Array<*>} params
-		 * An array of arbitrary values which will be passed as arguments
-		 * to the constructor function.
-		 *
-		 * @param {...*} [new_args]
-		 * Specifies arguments to be passed to the subclass constructor
-		 * as-is in order to instantiate the new subclass.
-		 *
-		 * @returns {LuCI.Class}
-		 * Returns a new LuCI.Class instance extended by the given
-		 * properties with its prototype set to this base class to
-		 * enable inheritance.
-		 */
-		instantiate: function(args) {
-			return new (Function.prototype.bind.apply(this,
-				Class.prototype.varargs(args, 0, null)))();
-		},
-
-		/* unused */
-		call: function(self, method) {
-			if (typeof(this.prototype[method]) != 'function')
-				throw new ReferenceError(method + ' is not defined in class');
-
-			return this.prototype[method].apply(self, self.varargs(arguments, 1));
-		},
-
-		/**
-		 * Checks whether the given class value is a subclass of this class.
-		 *
-		 * @memberof LuCI.Class
-		 *
-		 * @param {LuCI.Class} classValue
-		 * The class object to test.
-		 *
-		 * @returns {boolean}
-		 * Returns `true` when the given `classValue` is a subclass of this
-		 * class or `false` if the given value is not a valid class or not
-		 * a subclass of this class'.
-		 */
-		isSubclass: function(classValue) {
-			return (classValue != null &&
-			        typeof(classValue) == 'function' &&
-			        classValue.prototype instanceof this);
-		},
-
-		prototype: {
-			/**
-			 * Extract all values from the given argument array beginning from
-			 * `offset` and prepend any further given optional parameters to
-			 * the beginning of the resulting array copy.
-			 *
-			 * @memberof LuCI.Class
-			 * @instance
-			 *
-			 * @param {Array<*>} args
-			 * The array to extract the values from.
-			 *
-			 * @param {number} offset
-			 * The offset from which to extract the values. An offset of `0`
-			 * would copy all values till the end.
-			 *
-			 * @param {...*} [extra_args]
-			 * Extra arguments to add to prepend to the resultung array.
-			 *
-			 * @returns {Array<*>}
-			 * Returns a new array consisting of the optional extra arguments
-			 * and the values extracted from the `args` array beginning with
-			 * `offset`.
-			 */
-			varargs: function(args, offset /*, ... */) {
-				return Array.prototype.slice.call(arguments, 2)
-					.concat(Array.prototype.slice.call(args, offset));
-			},
-
-			/**
-			 * Walks up the parent class chain and looks for a class member
-			 * called `key` in any of the parent classes this class inherits
-			 * from. Returns the member value of the superclass or calls the
-			 * member as function and returns its return value when the
-			 * optional `callArgs` array is given.
-			 *
-			 * This function has two signatures and is sensitive to the
-			 * amount of arguments passed to it:
-			 *  - `super('key')` -
-			 *    Returns the value of `key` when found within one of the
-			 *    parent classes.
-			 *  - `super('key', ['arg1', 'arg2'])` -
-			 *    Calls the `key()` method with parameters `arg1` and `arg2`
-			 *    when found within one of the parent classes.
-			 *
-			 * @memberof LuCI.Class
-			 * @instance
-			 *
-			 * @param {string} key
-			 * The name of the superclass member to retrieve.
-			 *
-			 * @param {Array<*>} [callArgs]
-			 * An optional array of function call parameters to use. When
-			 * this parameter is specified, the found member value is called
-			 * as function using the values of this array as arguments.
-			 *
-			 * @throws {ReferenceError}
-			 * Throws a `ReferenceError` when `callArgs` are specified and
-			 * the found member named by `key` is not a function value.
-			 *
-			 * @returns {*|null}
-			 * Returns the value of the found member or the return value of
-			 * the call to the found method. Returns `null` when no member
-			 * was found in the parent class chain or when the call to the
-			 * superclass method returned `null`.
-			 */
-			super: function(key, callArgs) {
-				for (superContext = Object.getPrototypeOf(superContext ||
-				                                          Object.getPrototypeOf(this));
-				     superContext && !superContext.hasOwnProperty(key);
-				     superContext = Object.getPrototypeOf(superContext)) { }
-
-				if (!superContext)
-					return null;
-
-				var res = superContext[key];
-
-				if (arguments.length > 1) {
-					if (typeof(res) != 'function')
-						throw new ReferenceError(key + ' is not a function in base class');
-
-					if (typeof(callArgs) != 'object')
-						callArgs = this.varargs(arguments, 1);
-
-					res = res.apply(this, callArgs);
-				}
-
-				superContext = null;
-
-				return res;
-			},
-
-			/**
-			 * Returns a string representation of this class.
-			 *
-			 * @returns {string}
-			 * Returns a string representation of this class containing the
-			 * constructor functions `displayName` and describing the class
-			 * members and their respective types.
-			 */
-			toString: function() {
-				var s = '[' + this.constructor.displayName + ']', f = true;
-				for (var k in this) {
-					if (this.hasOwnProperty(k)) {
-						s += (f ? ' {\n' : '') + '  ' + k + ': ' + typeof(this[k]) + '\n';
-						f = false;
-					}
-				}
-				return s + (f ? '' : '}');
-			}
-		}
-	});
-
-
-	/**
-	 * @class
-	 * @memberof LuCI
-	 * @hideconstructor
-	 * @classdesc
-	 *
-	 * The `Headers` class is an internal utility class exposed in HTTP
-	 * response objects using the `response.headers` property.
-	 */
-	var Headers = Class.extend(/** @lends LuCI.Headers.prototype */ {
-		__name__: 'LuCI.XHR.Headers',
-		__init__: function(xhr) {
-			var hdrs = this.headers = {};
-			xhr.getAllResponseHeaders().split(/\r\n/).forEach(function(line) {
-				var m = /^([^:]+):(.*)$/.exec(line);
-				if (m != null)
-					hdrs[m[1].trim().toLowerCase()] = m[2].trim();
-			});
-		},
-
-		/**
-		 * Checks whether the given header name is present.
-		 * Note: Header-Names are case-insensitive.
-		 *
-		 * @instance
-		 * @memberof LuCI.Headers
-		 * @param {string} name
-		 * The header name to check
-		 *
-		 * @returns {boolean}
-		 * Returns `true` if the header name is present, `false` otherwise
-		 */
-		has: function(name) {
-			return this.headers.hasOwnProperty(String(name).toLowerCase());
-		},
-
-		/**
-		 * Returns the value of the given header name.
-		 * Note: Header-Names are case-insensitive.
-		 *
-		 * @instance
-		 * @memberof LuCI.Headers
-		 * @param {string} name
-		 * The header name to read
-		 *
-		 * @returns {string|null}
-		 * The value of the given header name or `null` if the header isn't present.
-		 */
-		get: function(name) {
-			var key = String(name).toLowerCase();
-			return this.headers.hasOwnProperty(key) ? this.headers[key] : null;
-		}
-	});
-
-	/**
-	 * @class
-	 * @memberof LuCI
-	 * @hideconstructor
-	 * @classdesc
-	 *
-	 * The `Response` class is an internal utility class representing HTTP responses.
-	 */
-	var Response = Class.extend({
-		__name__: 'LuCI.XHR.Response',
-		__init__: function(xhr, url, duration, headers, content) {
-			/**
-			 * Describes whether the response is successful (status codes `200..299`) or not
-			 * @instance
-			 * @memberof LuCI.Response
-			 * @name ok
-			 * @type {boolean}
-			 */
-			this.ok = (xhr.status >= 200 && xhr.status <= 299);
-
-			/**
-			 * The numeric HTTP status code of the response
-			 * @instance
-			 * @memberof LuCI.Response
-			 * @name status
-			 * @type {number}
-			 */
-			this.status = xhr.status;
-
-			/**
-			 * The HTTP status description message of the response
-			 * @instance
-			 * @memberof LuCI.Response
-			 * @name statusText
-			 * @type {string}
-			 */
-			this.statusText = xhr.statusText;
-
-			/**
-			 * The HTTP headers of the response
-			 * @instance
-			 * @memberof LuCI.Response
-			 * @name headers
-			 * @type {LuCI.Headers}
-			 */
-			this.headers = (headers != null) ? headers : new Headers(xhr);
-
-			/**
-			 * The total duration of the HTTP request in milliseconds
-			 * @instance
-			 * @memberof LuCI.Response
-			 * @name duration
-			 * @type {number}
-			 */
-			this.duration = duration;
-
-			/**
-			 * The final URL of the request, i.e. after following redirects.
-			 * @instance
-			 * @memberof LuCI.Response
-			 * @name url
-			 * @type {string}
-			 */
-			this.url = url;
-
-			/* privates */
-			this.xhr = xhr;
-
-			if (content != null && typeof(content) == 'object') {
-				this.responseJSON = content;
-				this.responseText = null;
-			}
-			else if (content != null) {
-				this.responseJSON = null;
-				this.responseText = String(content);
-			}
-			else {
-				this.responseJSON = null;
-				this.responseText = xhr.responseText;
-			}
-		},
-
-		/**
-		 * Clones the given response object, optionally overriding the content
-		 * of the cloned instance.
-		 *
-		 * @instance
-		 * @memberof LuCI.Response
-		 * @param {*} [content]
-		 * Override the content of the cloned response. Object values will be
-		 * treated as JSON response data, all other types will be converted
-		 * using `String()` and treated as response text.
-		 *
-		 * @returns {LuCI.Response}
-		 * The cloned `Response` instance.
-		 */
-		clone: function(content) {
-			var copy = new Response(this.xhr, this.url, this.duration, this.headers, content);
-
-			copy.ok = this.ok;
-			copy.status = this.status;
-			copy.statusText = this.statusText;
-
-			return copy;
-		},
-
-		/**
-		 * Access the response content as JSON data.
-		 *
-		 * @instance
-		 * @memberof LuCI.Response
-		 * @throws {SyntaxError}
-		 * Throws `SyntaxError` if the content isn't valid JSON.
-		 *
-		 * @returns {*}
-		 * The parsed JSON data.
-		 */
-		json: function() {
-			if (this.responseJSON == null)
-				this.responseJSON = JSON.parse(this.responseText);
-
-			return this.responseJSON;
-		},
-
-		/**
-		 * Access the response content as string.
-		 *
-		 * @instance
-		 * @memberof LuCI.Response
-		 * @returns {string}
-		 * The response content.
-		 */
-		text: function() {
-			if (this.responseText == null && this.responseJSON != null)
-				this.responseText = JSON.stringify(this.responseJSON);
-
-			return this.responseText;
-		}
-	});
-
-
-	var requestQueue = [];
-
-	function isQueueableRequest(opt) {
-		if (!classes.rpc)
-			return false;
-
-		if (opt.method != 'POST' || typeof(opt.content) != 'object')
-			return false;
-
-		if (opt.nobatch === true)
-			return false;
-
-		var rpcBaseURL = Request.expandURL(classes.rpc.getBaseURL());
-
-		return (rpcBaseURL != null && opt.url.indexOf(rpcBaseURL) == 0);
-	}
-
-	function flushRequestQueue() {
-		if (!requestQueue.length)
-			return;
-
-		var reqopt = Object.assign({}, requestQueue[0][0], { content: [], nobatch: true }),
-		    batch = [];
-
-		for (var i = 0; i < requestQueue.length; i++) {
-			batch[i] = requestQueue[i];
-			reqopt.content[i] = batch[i][0].content;
-		}
-
-		requestQueue.length = 0;
-
-		Request.request(rpcBaseURL, reqopt).then(function(reply) {
-			var json = null, req = null;
-
-			try { json = reply.json() }
-			catch(e) { }
-
-			while ((req = batch.shift()) != null)
-				if (Array.isArray(json) && json.length)
-					req[2].call(reqopt, reply.clone(json.shift()));
-				else
-					req[1].call(reqopt, new Error('No related RPC reply'));
-		}).catch(function(error) {
-			var req = null;
-
-			while ((req = batch.shift()) != null)
-				req[1].call(reqopt, error);
-		});
-	}
-
-	/**
-	 * @class
-	 * @memberof LuCI
-	 * @hideconstructor
-	 * @classdesc
-	 *
-	 * The `Request` class allows initiating HTTP requests and provides utilities
-	 * for dealing with responses.
-	 */
-	var Request = Class.singleton(/** @lends LuCI.Request.prototype */ {
-		__name__: 'LuCI.Request',
-
-		interceptors: [],
-
-		/**
-		 * Turn the given relative URL into an absolute URL if necessary.
-		 *
-		 * @instance
-		 * @memberof LuCI.Request
-		 * @param {string} url
-		 * The URL to convert.
-		 *
-		 * @returns {string}
-		 * The absolute URL derived from the given one, or the original URL
-		 * if it already was absolute.
-		 */
-		expandURL: function(url) {
-			if (!/^(?:[^/]+:)?\/\//.test(url))
-				url = location.protocol + '//' + location.host + url;
-
-			return url;
-		},
-
-		/**
-		 * @typedef {Object} RequestOptions
-		 * @memberof LuCI.Request
-		 *
-		 * @property {string} [method=GET]
-		 * The HTTP method to use, e.g. `GET` or `POST`.
-		 *
-		 * @property {Object<string, Object|string>} [query]
-		 * Query string data to append to the URL. Non-string values of the
-		 * given object will be converted to JSON.
-		 *
-		 * @property {boolean} [cache=false]
-		 * Specifies whether the HTTP response may be retrieved from cache.
-		 *
-		 * @property {string} [username]
-		 * Provides a username for HTTP basic authentication.
-		 *
-		 * @property {string} [password]
-		 * Provides a password for HTTP basic authentication.
-		 *
-		 * @property {number} [timeout]
-		 * Specifies the request timeout in seconds.
-		 *
-		 * @property {boolean} [credentials=false]
-		 * Whether to include credentials such as cookies in the request.
-		 *
-		 * @property {*} [content]
-		 * Specifies the HTTP message body to send along with the request.
-		 * If the value is a function, it is invoked and the return value
-		 * used as content, if it is a FormData instance, it is used as-is,
-		 * if it is an object, it will be converted to JSON, in all other
-		 * cases it is converted to a string.
-		 *
-	     * @property {Object<string, string>} [header]
-	     * Specifies HTTP headers to set for the request.
-	     *
-	     * @property {function} [progress]
-	     * An optional request callback function which receives ProgressEvent
-	     * instances as sole argument during the HTTP request transfer.
-		 */
-
-		/**
-		 * Initiate an HTTP request to the given target.
-		 *
-		 * @instance
-		 * @memberof LuCI.Request
-		 * @param {string} target
-		 * The URL to request.
-		 *
-		 * @param {LuCI.Request.RequestOptions} [options]
-		 * Additional options to configure the request.
-		 *
-		 * @returns {Promise<LuCI.Response>}
-		 * The resulting HTTP response.
-		 */
-		request: function(target, options) {
-			var state = { xhr: new XMLHttpRequest(), url: this.expandURL(target), start: Date.now() },
-			    opt = Object.assign({}, options, state),
-			    content = null,
-			    contenttype = null,
-			    callback = this.handleReadyStateChange;
-
-			return new Promise(function(resolveFn, rejectFn) {
-				opt.xhr.onreadystatechange = callback.bind(opt, resolveFn, rejectFn);
-				opt.method = String(opt.method || 'GET').toUpperCase();
-
-				if ('query' in opt) {
-					var q = (opt.query != null) ? Object.keys(opt.query).map(function(k) {
-						if (opt.query[k] != null) {
-							var v = (typeof(opt.query[k]) == 'object')
-								? JSON.stringify(opt.query[k])
-								: String(opt.query[k]);
-
-							return '%s=%s'.format(encodeURIComponent(k), encodeURIComponent(v));
-						}
-						else {
-							return encodeURIComponent(k);
-						}
-					}).join('&') : '';
-
-					if (q !== '') {
-						switch (opt.method) {
-						case 'GET':
-						case 'HEAD':
-						case 'OPTIONS':
-							opt.url += ((/\?/).test(opt.url) ? '&' : '?') + q;
-							break;
-
-						default:
-							if (content == null) {
-								content = q;
-								contenttype = 'application/x-www-form-urlencoded';
-							}
-						}
-					}
-				}
-
-				if (!opt.cache)
-					opt.url += ((/\?/).test(opt.url) ? '&' : '?') + (new Date()).getTime();
-
-				if (isQueueableRequest(opt)) {
-					requestQueue.push([opt, rejectFn, resolveFn]);
-					requestAnimationFrame(flushRequestQueue);
-					return;
-				}
-
-				if ('username' in opt && 'password' in opt)
-					opt.xhr.open(opt.method, opt.url, true, opt.username, opt.password);
-				else
-					opt.xhr.open(opt.method, opt.url, true);
-
-				opt.xhr.responseType = 'text';
-
-				if ('overrideMimeType' in opt.xhr)
-					opt.xhr.overrideMimeType('application/octet-stream');
-
-				if ('timeout' in opt)
-					opt.xhr.timeout = +opt.timeout;
-
-				if ('credentials' in opt)
-					opt.xhr.withCredentials = !!opt.credentials;
-
-				if (opt.content != null) {
-					switch (typeof(opt.content)) {
-					case 'function':
-						content = opt.content(xhr);
-						break;
-
-					case 'object':
-						if (!(opt.content instanceof FormData)) {
-							content = JSON.stringify(opt.content);
-							contenttype = 'application/json';
-						}
-						else {
-							content = opt.content;
-						}
-						break;
-
-					default:
-						content = String(opt.content);
-					}
-				}
-
-				if ('headers' in opt)
-					for (var header in opt.headers)
-						if (opt.headers.hasOwnProperty(header)) {
-							if (header.toLowerCase() != 'content-type')
-								opt.xhr.setRequestHeader(header, opt.headers[header]);
-							else
-								contenttype = opt.headers[header];
-						}
-
-				if ('progress' in opt && 'upload' in opt.xhr)
-					opt.xhr.upload.addEventListener('progress', opt.progress);
-
-				if (contenttype != null)
-					opt.xhr.setRequestHeader('Content-Type', contenttype);
-
-				try {
-					opt.xhr.send(content);
-				}
-				catch (e) {
-					rejectFn.call(opt, e);
-				}
-			});
-		},
-
-		handleReadyStateChange: function(resolveFn, rejectFn, ev) {
-			var xhr = this.xhr,
-			    duration = Date.now() - this.start;
-
-			if (xhr.readyState !== 4)
-				return;
-
-			if (xhr.status === 0 && xhr.statusText === '') {
-				if (duration >= this.timeout)
-					rejectFn.call(this, new Error('XHR request timed out'));
-				else
-					rejectFn.call(this, new Error('XHR request aborted by browser'));
-			}
-			else {
-				var response = new Response(
-					xhr, xhr.responseURL || this.url, duration);
-
-				Promise.all(Request.interceptors.map(function(fn) { return fn(response) }))
-					.then(resolveFn.bind(this, response))
-					.catch(rejectFn.bind(this));
-			}
-		},
-
-		/**
-		 * Initiate an HTTP GET request to the given target.
-		 *
-		 * @instance
-		 * @memberof LuCI.Request
-		 * @param {string} target
-		 * The URL to request.
-		 *
-		 * @param {LuCI.Request.RequestOptions} [options]
-		 * Additional options to configure the request.
-		 *
-		 * @returns {Promise<LuCI.Response>}
-		 * The resulting HTTP response.
-		 */
-		get: function(url, options) {
-			return this.request(url, Object.assign({ method: 'GET' }, options));
-		},
-
-		/**
-		 * Initiate an HTTP POST request to the given target.
-		 *
-		 * @instance
-		 * @memberof LuCI.Request
-		 * @param {string} target
-		 * The URL to request.
-		 *
-		 * @param {*} [data]
-		 * The request data to send, see {@link LuCI.Request.RequestOptions} for details.
-		 *
-		 * @param {LuCI.Request.RequestOptions} [options]
-		 * Additional options to configure the request.
-		 *
-		 * @returns {Promise<LuCI.Response>}
-		 * The resulting HTTP response.
-		 */
-		post: function(url, data, options) {
-			return this.request(url, Object.assign({ method: 'POST', content: data }, options));
-		},
-
-		/**
-		 * Interceptor functions are invoked whenever an HTTP reply is received, in the order
-		 * these functions have been registered.
-		 * @callback LuCI.Request.interceptorFn
-		 * @param {LuCI.Response} res
-		 * The HTTP response object
-		 */
-
-		/**
-		 * Register an HTTP response interceptor function. Interceptor
-		 * functions are useful to perform default actions on incoming HTTP
-		 * responses, such as checking for expired authentication or for
-		 * implementing request retries before returning a failure.
-		 *
-		 * @instance
-		 * @memberof LuCI.Request
-		 * @param {LuCI.Request.interceptorFn} interceptorFn
-		 * The interceptor function to register.
-		 *
-		 * @returns {LuCI.Request.interceptorFn}
-		 * The registered function.
-		 */
-		addInterceptor: function(interceptorFn) {
-			if (typeof(interceptorFn) == 'function')
-				this.interceptors.push(interceptorFn);
-			return interceptorFn;
-		},
-
-		/**
-		 * Remove an HTTP response interceptor function. The passed function
-		 * value must be the very same value that was used to register the
-		 * function.
-		 *
-		 * @instance
-		 * @memberof LuCI.Request
-		 * @param {LuCI.Request.interceptorFn} interceptorFn
-		 * The interceptor function to remove.
-		 *
-		 * @returns {boolean}
-		 * Returns `true` if any function has been removed, else `false`.
-		 */
-		removeInterceptor: function(interceptorFn) {
-			var oldlen = this.interceptors.length, i = oldlen;
-			while (i--)
-				if (this.interceptors[i] === interceptorFn)
-					this.interceptors.splice(i, 1);
-			return (this.interceptors.length < oldlen);
-		},
-
-		/**
-		 * @class
-		 * @memberof LuCI.Request
-		 * @hideconstructor
-		 * @classdesc
-		 *
-		 * The `Request.poll` class provides some convience wrappers around
-		 * {@link LuCI.Poll} mainly to simplify registering repeating HTTP
-		 * request calls as polling functions.
-		 */
-		poll: {
-			/**
-			 * The callback function is invoked whenever an HTTP reply to a
-			 * polled request is received or when the polled request timed
-			 * out.
-			 *
-			 * @callback LuCI.Request.poll~callbackFn
-			 * @param {LuCI.Response} res
-			 * The HTTP response object.
-			 *
-			 * @param {*} data
-			 * The response JSON if the response could be parsed as such,
-			 * else `null`.
-			 *
-			 * @param {number} duration
-			 * The total duration of the request in milliseconds.
-			 */
-
-			/**
-			 * Register a repeating HTTP request with an optional callback
-			 * to invoke whenever a response for the request is received.
-			 *
-			 * @instance
-			 * @memberof LuCI.Request.poll
-			 * @param {number} interval
-			 * The poll interval in seconds.
-			 *
-			 * @param {string} url
-			 * The URL to request on each poll.
-			 *
-			 * @param {LuCI.Request.RequestOptions} [options]
-			 * Additional options to configure the request.
-			 *
-			 * @param {LuCI.Request.poll~callbackFn} [callback]
-			 * {@link LuCI.Request.poll~callbackFn Callback} function to
-			 * invoke for each HTTP reply.
-			 *
-			 * @throws {TypeError}
-			 * Throws `TypeError` when an invalid interval was passed.
-			 *
-			 * @returns {function}
-			 * Returns the internally created poll function.
-			 */
-			add: function(interval, url, options, callback) {
-				if (isNaN(interval) || interval <= 0)
-					throw new TypeError('Invalid poll interval');
-
-				var ival = interval >>> 0,
-				    opts = Object.assign({}, options, { timeout: ival * 1000 - 5 });
-
-				var fn = function() {
-					return Request.request(url, options).then(function(res) {
-						if (!Poll.active())
-							return;
-
-						try {
-							callback(res, res.json(), res.duration);
-						}
-						catch (err) {
-							callback(res, null, res.duration);
-						}
-					});
-				};
-
-				return (Poll.add(fn, ival) ? fn : null);
-			},
-
-			/**
-			 * Remove a polling request that has been previously added using `add()`.
-			 * This function is essentially a wrapper around
-			 * {@link LuCI.Poll.remove LuCI.Poll.remove()}.
-			 *
-			 * @instance
-			 * @memberof LuCI.Request.poll
-			 * @param {function} entry
-			 * The poll function returned by {@link LuCI.Request.poll#add add()}.
-			 *
-			 * @returns {boolean}
-			 * Returns `true` if any function has been removed, else `false`.
-			 */
-			remove: function(entry) { return Poll.remove(entry) },
-
-			/**
-			  * Alias for {@link LuCI.Poll.start LuCI.Poll.start()}.
-			  *
-			  * @instance
-			  * @memberof LuCI.Request.poll
-			  */
-			start: function() { return Poll.start() },
-
-			/**
-			  * Alias for {@link LuCI.Poll.stop LuCI.Poll.stop()}.
-			  *
-			  * @instance
-			  * @memberof LuCI.Request.poll
-			  */
-			stop: function() { return Poll.stop() },
-
-			/**
-			  * Alias for {@link LuCI.Poll.active LuCI.Poll.active()}.
-			  *
-			  * @instance
-			  * @memberof LuCI.Request.poll
-			  */
-			active: function() { return Poll.active() }
-		}
-	});
-
-	/**
-	 * @class
-	 * @memberof LuCI
-	 * @hideconstructor
-	 * @classdesc
-	 *
-	 * The `Poll` class allows registering and unregistering poll actions,
-	 * as well as starting, stopping and querying the state of the polling
-	 * loop.
-	 */
-	var Poll = Class.singleton(/** @lends LuCI.Poll.prototype */ {
-		__name__: 'LuCI.Poll',
-
-		queue: [],
-
-		/**
-		 * Add a new operation to the polling loop. If the polling loop is not
-		 * already started at this point, it will be implicitely started.
-		 *
-		 * @instance
-		 * @memberof LuCI.Poll
-		 * @param {function} fn
-		 * The function to invoke on each poll interval.
-		 *
-		 * @param {number} interval
-		 * The poll interval in seconds.
-		 *
-		 * @throws {TypeError}
-		 * Throws `TypeError` when an invalid interval was passed.
-		 *
-		 * @returns {boolean}
-		 * Returns `true` if the function has been added or `false` if it
-		 * already is registered.
-		 */
-		add: function(fn, interval) {
-			if (interval == null || interval <= 0)
-				interval = window.L ? window.L.env.pollinterval : null;
-
-			if (isNaN(interval) || typeof(fn) != 'function')
-				throw new TypeError('Invalid argument to LuCI.Poll.add()');
-
-			for (var i = 0; i < this.queue.length; i++)
-				if (this.queue[i].fn === fn)
-					return false;
-
-			var e = {
-				r: true,
-				i: interval >>> 0,
-				fn: fn
-			};
-
-			this.queue.push(e);
-
-			if (this.tick != null && !this.active())
-				this.start();
-
-			return true;
-		},
-
-		/**
-		 * Remove an operation from the polling loop. If no further operatons
-		 * are registered, the polling loop is implicitely stopped.
-		 *
-		 * @instance
-		 * @memberof LuCI.Poll
-		 * @param {function} fn
-		 * The function to remove.
-		 *
-		 * @throws {TypeError}
-		 * Throws `TypeError` when the given argument isn't a function.
-		 *
-		 * @returns {boolean}
-		 * Returns `true` if the function has been removed or `false` if it
-		 * wasn't found.
-		 */
-		remove: function(fn) {
-			if (typeof(fn) != 'function')
-				throw new TypeError('Invalid argument to LuCI.Poll.remove()');
-
-			var len = this.queue.length;
-
-			for (var i = len; i > 0; i--)
-				if (this.queue[i-1].fn === fn)
-					this.queue.splice(i-1, 1);
-
-			if (!this.queue.length && this.stop())
-				this.tick = 0;
-
-			return (this.queue.length != len);
-		},
-
-		/**
-		 * (Re)start the polling loop. Dispatches a custom `poll-start` event
-		 * to the `document` object upon successful start.
-		 *
-		 * @instance
-		 * @memberof LuCI.Poll
-		 * @returns {boolean}
-		 * Returns `true` if polling has been started (or if no functions
-		 * where registered) or `false` when the polling loop already runs.
-		 */
-		start: function() {
-			if (this.active())
-				return false;
-
-			this.tick = 0;
-
-			if (this.queue.length) {
-				this.timer = window.setInterval(this.step, 1000);
-				this.step();
-				document.dispatchEvent(new CustomEvent('poll-start'));
-			}
-
-			return true;
-		},
-
-		/**
-		 * Stop the polling loop. Dispatches a custom `poll-stop` event
-		 * to the `document` object upon successful stop.
-		 *
-		 * @instance
-		 * @memberof LuCI.Poll
-		 * @returns {boolean}
-		 * Returns `true` if polling has been stopped or `false` if it din't
-		 * run to begin with.
-		 */
-		stop: function() {
-			if (!this.active())
-				return false;
-
-			document.dispatchEvent(new CustomEvent('poll-stop'));
-			window.clearInterval(this.timer);
-			delete this.timer;
-			delete this.tick;
-			return true;
-		},
-
-		/* private */
-		step: function() {
-			for (var i = 0, e = null; (e = Poll.queue[i]) != null; i++) {
-				if ((Poll.tick % e.i) != 0)
-					continue;
-
-				if (!e.r)
-					continue;
-
-				e.r = false;
-
-				Promise.resolve(e.fn()).finally((function() { this.r = true }).bind(e));
-			}
-
-			Poll.tick = (Poll.tick + 1) % Math.pow(2, 32);
-		},
-
-		/**
-		 * Test whether the polling loop is running.
-		 *
-		 * @instance
-		 * @memberof LuCI.Poll
-		 * @returns {boolean} - Returns `true` if polling is active, else `false`.
-		 */
-		active: function() {
-			return (this.timer != null);
-		}
-	});
-
-
-	var dummyElem = null,
-	    domParser = null,
-	    originalCBIInit = null,
-	    rpcBaseURL = null,
-	    sysFeatures = null,
-	    classes = {};
-
-	var LuCI = Class.extend(/** @lends LuCI.prototype */ {
-		__name__: 'LuCI',
-		__init__: function(env) {
-
-			document.querySelectorAll('script[src*="/luci.js"]').forEach(function(s) {
-				if (env.base_url == null || env.base_url == '') {
-					var m = (s.getAttribute('src') || '').match(/^(.*)\/luci\.js(?:\?v=([^?]+))?$/);
-					if (m) {
-						env.base_url = m[1];
-						env.resource_version = m[2];
-					}
-				}
-			});
-
-			if (env.base_url == null)
-				this.error('InternalError', 'Cannot find url of luci.js');
-
-			Object.assign(this.env, env);
-
-			document.addEventListener('poll-start', function(ev) {
-				document.querySelectorAll('[id^="xhr_poll_status"]').forEach(function(e) {
-					e.style.display = (e.id == 'xhr_poll_status_off') ? 'none' : '';
-				});
-			});
-
-			document.addEventListener('poll-stop', function(ev) {
-				document.querySelectorAll('[id^="xhr_poll_status"]').forEach(function(e) {
-					e.style.display = (e.id == 'xhr_poll_status_on') ? 'none' : '';
-				});
-			});
-
-			var domReady = new Promise(function(resolveFn, rejectFn) {
-				document.addEventListener('DOMContentLoaded', resolveFn);
-			});
-
-			Promise.all([
-				domReady,
-				this.require('ui'),
-				this.require('rpc'),
-				this.require('form'),
-				this.probeRPCBaseURL()
-			]).then(this.setupDOM.bind(this)).catch(this.error);
-
-			originalCBIInit = window.cbi_init;
-			window.cbi_init = function() {};
-		},
-
-		/**
-		 * Captures the current stack trace and throws an error of the
-		 * specified type as a new exception. Also logs the exception as
-		 * error to the debug console if it is available.
-		 *
-		 * @instance
-		 * @memberof LuCI
-		 *
-		 * @param {Error|string} [type=Error]
-		 * Either a string specifying the type of the error to throw or an
-		 * existing `Error` instance to copy.
-		 *
-		 * @param {string} [fmt=Unspecified error]
-		 * A format string which is used to form the error message, together
-		 * with all subsequent optional arguments.
-		 *
-		 * @param {...*} [args]
-		 * Zero or more variable arguments to the supplied format string.
-		 *
-		 * @throws {Error}
-		 * Throws the created error object with the captured stack trace
-		 * appended to the message and the type set to the given type
-		 * argument or copied from the given error instance.
-		 */
-		raise: function(type, fmt /*, ...*/) {
-			var e = null,
-			    msg = fmt ? String.prototype.format.apply(fmt, this.varargs(arguments, 2)) : null,
-			    stack = null;
-
-			if (type instanceof Error) {
-				e = type;
-
-				if (msg)
-					e.message = msg + ': ' + e.message;
-			}
-			else {
-				try { throw new Error('stacktrace') }
-				catch (e2) { stack = (e2.stack || '').split(/\n/) }
-
-				e = new (window[type || 'Error'] || Error)(msg || 'Unspecified error');
-				e.name = type || 'Error';
-			}
-
-			stack = (stack || []).map(function(frame) {
-				frame = frame.replace(/(.*?)@(.+):(\d+):(\d+)/g, 'at $1 ($2:$3:$4)').trim();
-				return frame ? '  ' + frame : '';
-			});
-
-			if (!/^  at /.test(stack[0]))
-				stack.shift();
-
-			if (/\braise /.test(stack[0]))
-				stack.shift();
-
-			if (/\berror /.test(stack[0]))
-				stack.shift();
-
-			if (stack.length)
-				e.message += '\n' + stack.join('\n');
-
-			if (window.console && console.debug)
-				console.debug(e);
-
-			throw e;
-		},
-
-		/**
-		 * A wrapper around {@link LuCI#raise raise()} which also renders
-		 * the error either as modal overlay when `ui.js` is already loaed
-		 * or directly into the view body.
-		 *
-		 * @instance
-		 * @memberof LuCI
-		 *
-		 * @param {Error|string} [type=Error]
-		 * Either a string specifying the type of the error to throw or an
-		 * existing `Error` instance to copy.
-		 *
-		 * @param {string} [fmt=Unspecified error]
-		 * A format string which is used to form the error message, together
-		 * with all subsequent optional arguments.
-		 *
-		 * @param {...*} [args]
-		 * Zero or more variable arguments to the supplied format string.
-		 *
-		 * @throws {Error}
-		 * Throws the created error object with the captured stack trace
-		 * appended to the message and the type set to the given type
-		 * argument or copied from the given error instance.
-		 */
-		error: function(type, fmt /*, ...*/) {
-			try {
-				L.raise.apply(L, Array.prototype.slice.call(arguments));
-			}
-			catch (e) {
-				if (!e.reported) {
-					if (L.ui)
-						L.ui.addNotification(e.name || _('Runtime error'),
-							E('pre', {}, e.message), 'danger');
-					else
-						L.dom.content(document.querySelector('#maincontent'),
-							E('pre', { 'class': 'alert-message error' }, e.message));
-
-					e.reported = true;
-				}
-
-				throw e;
-			}
-		},
-
-		/**
-		 * Return a bound function using the given `self` as `this` context
-		 * and any further arguments as parameters to the bound function.
-		 *
-		 * @instance
-		 * @memberof LuCI
-		 *
-		 * @param {function} fn
-		 * The function to bind.
-		 *
-		 * @param {*} self
-		 * The value to bind as `this` context to the specified function.
-		 *
-		 * @param {...*} [args]
-		 * Zero or more variable arguments which are bound to the function
-		 * as parameters.
-		 *
-		 * @returns {function}
-		 * Returns the bound function.
-		 */
-		bind: function(fn, self /*, ... */) {
-			return Function.prototype.bind.apply(fn, this.varargs(arguments, 2, self));
-		},
-
-		/**
-		 * Load an additional LuCI JavaScript class and its dependencies,
-		 * instantiate it and return the resulting class instance. Each
-		 * class is only loaded once. Subsequent attempts to load the same
-		 * class will return the already instantiated class.
-		 *
-		 * @instance
-		 * @memberof LuCI
-		 *
-		 * @param {string} name
-		 * The name of the class to load in dotted notation. Dots will
-		 * be replaced by spaces and joined with the runtime-determined
-		 * base URL of LuCI.js to form an absolute URL to load the class
-		 * file from.
-		 *
-		 * @throws {DependencyError}
-		 * Throws a `DependencyError` when the class to load includes
-		 * circular dependencies.
-		 *
-		 * @throws {NetworkError}
-		 * Throws `NetworkError` when the underlying {@link LuCI.Request}
-		 * call failed.
-		 *
-		 * @throws {SyntaxError}
-		 * Throws `SyntaxError` when the loaded class file code cannot
-		 * be interpreted by `eval`.
-		 *
-		 * @throws {TypeError}
-		 * Throws `TypeError` when the class file could be loaded and
-		 * interpreted, but when invoking its code did not yield a valid
-		 * class instance.
-		 *
-		 * @returns {Promise<LuCI#Class>}
-		 * Returns the instantiated class.
-		 */
-		require: function(name, from) {
-			var L = this, url = null, from = from || [];
-
-			/* Class already loaded */
-			if (classes[name] != null) {
-				/* Circular dependency */
-				if (from.indexOf(name) != -1)
-					L.raise('DependencyError',
-						'Circular dependency: class "%s" depends on "%s"',
-						name, from.join('" which depends on "'));
-
-				return Promise.resolve(classes[name]);
-			}
-
-			url = '%s/%s.js%s'.format(L.env.base_url, name.replace(/\./g, '/'), (L.env.resource_version ? '?v=' + L.env.resource_version : ''));
-			from = [ name ].concat(from);
-
-			var compileClass = function(res) {
-				if (!res.ok)
-					L.raise('NetworkError',
-						'HTTP error %d while loading class file "%s"', res.status, url);
-
-				var source = res.text(),
-				    requirematch = /^require[ \t]+(\S+)(?:[ \t]+as[ \t]+([a-zA-Z_]\S*))?$/,
-				    strictmatch = /^use[ \t]+strict$/,
-				    depends = [],
-				    args = '';
-
-				/* find require statements in source */
-				for (var i = 0, off = -1, quote = -1, esc = false; i < source.length; i++) {
-					var chr = source.charCodeAt(i);
-
-					if (esc) {
-						esc = false;
-					}
-					else if (chr == 92) {
-						esc = true;
-					}
-					else if (chr == quote) {
-						var s = source.substring(off, i),
-						    m = requirematch.exec(s);
-
-						if (m) {
-							var dep = m[1], as = m[2] || dep.replace(/[^a-zA-Z0-9_]/g, '_');
-							depends.push(L.require(dep, from));
-							args += ', ' + as;
-						}
-						else if (!strictmatch.exec(s)) {
-							break;
-						}
-
-						off = -1;
-						quote = -1;
-					}
-					else if (quote == -1 && (chr == 34 || chr == 39)) {
-						off = i + 1;
-						quote = chr;
-					}
-				}
-
-				/* load dependencies and instantiate class */
-				return Promise.all(depends).then(function(instances) {
-					var _factory, _class;
-
-					try {
-						_factory = eval(
-							'(function(window, document, L%s) { %s })\n\n//# sourceURL=%s\n'
-								.format(args, source, res.url));
-					}
-					catch (error) {
-						L.raise('SyntaxError', '%s\n  in %s:%s',
-							error.message, res.url, error.lineNumber || '?');
-					}
-
-					_factory.displayName = toCamelCase(name + 'ClassFactory');
-					_class = _factory.apply(_factory, [window, document, L].concat(instances));
-
-					if (!Class.isSubclass(_class))
-					    L.error('TypeError', '"%s" factory yields invalid constructor', name);
-
-					if (_class.displayName == 'AnonymousClass')
-						_class.displayName = toCamelCase(name + 'Class');
-
-					var ptr = Object.getPrototypeOf(L),
-					    parts = name.split(/\./),
-					    instance = new _class();
-
-					for (var i = 0; ptr && i < parts.length - 1; i++)
-						ptr = ptr[parts[i]];
-
-					if (ptr)
-						ptr[parts[i]] = instance;
-
-					classes[name] = instance;
-
-					return instance;
-				});
-			};
-
-			/* Request class file */
-			classes[name] = Request.get(url, { cache: true }).then(compileClass);
-
-			return classes[name];
-		},
-
-		/* DOM setup */
-		probeRPCBaseURL: function() {
-			if (rpcBaseURL == null) {
-				try {
-					rpcBaseURL = window.sessionStorage.getItem('rpcBaseURL');
-				}
-				catch (e) { }
-			}
-
-			if (rpcBaseURL == null) {
-				var rpcFallbackURL = this.url('admin/ubus');
-
-				rpcBaseURL = Request.get('/ubus/').then(function(res) {
-					return (rpcBaseURL = (res.status == 400) ? '/ubus/' : rpcFallbackURL);
-				}, function() {
-					return (rpcBaseURL = rpcFallbackURL);
-				}).then(function(url) {
-					try {
-						window.sessionStorage.setItem('rpcBaseURL', url);
-					}
-					catch (e) { }
-
-					return url;
-				});
-			}
-
-			return Promise.resolve(rpcBaseURL);
-		},
-
-		probeSystemFeatures: function() {
-			var sessionid = classes.rpc.getSessionID();
-
-			if (sysFeatures == null) {
-				try {
-					var data = JSON.parse(window.sessionStorage.getItem('sysFeatures'));
-
-					if (this.isObject(data) && this.isObject(data[sessionid]))
-						sysFeatures = data[sessionid];
-				}
-				catch (e) {}
-			}
-
-			if (!this.isObject(sysFeatures)) {
-				sysFeatures = classes.rpc.declare({
-					object: 'luci',
-					method: 'getFeatures',
-					expect: { '': {} }
-				})().then(function(features) {
-					try {
-						var data = {};
-						    data[sessionid] = features;
-
-						window.sessionStorage.setItem('sysFeatures', JSON.stringify(data));
-					}
-					catch (e) {}
-
-					sysFeatures = features;
-
-					return features;
-				});
-			}
-
-			return Promise.resolve(sysFeatures);
-		},
-
-		/**
-		 * Test whether a particular system feature is available, such as
-		 * hostapd SAE support or an installed firewall. The features are
-		 * queried once at the beginning of the LuCI session and cached in
-		 * `SessionStorage` throughout the lifetime of the associated tab or
-		 * browser window.
-		 *
-		 * @instance
-		 * @memberof LuCI
-		 *
-		 * @param {string} feature
-		 * The feature to test. For detailed list of known feature flags,
-		 * see `/modules/luci-base/root/usr/libexec/rpcd/luci`.
-		 *
-		 * @param {string} [subfeature]
-		 * Some feature classes like `hostapd` provide sub-feature flags,
-		 * such as `sae` or `11w` support. The `subfeature` argument can
-		 * be used to query these.
-		 *
-		 * @return {boolean|null}
-		 * Return `true` if the queried feature (and sub-feature) is available
-		 * or `false` if the requested feature isn't present or known.
-		 * Return `null` when a sub-feature was queried for a feature which
-		 * has no sub-features.
-		 */
-		hasSystemFeature: function() {
-			var ft = sysFeatures[arguments[0]];
-
-			if (arguments.length == 2)
-				return this.isObject(ft) ? ft[arguments[1]] : null;
-
-			return (ft != null && ft != false);
-		},
-
-		/* private */
-		notifySessionExpiry: function() {
-			Poll.stop();
-
-			L.ui.showModal(_('Session expired'), [
-				E('div', { class: 'alert-message warning' },
-					_('A new login is required since the authentication session expired.')),
-				E('div', { class: 'right' },
-					E('div', {
-						class: 'btn primary',
-						click: function() {
-							var loc = window.location;
-							window.location = loc.protocol + '//' + loc.host + loc.pathname + loc.search;
-						}
-					}, _('To login…')))
-			]);
-
-			L.raise('SessionError', 'Login session is expired');
-		},
-
-		/* private */
-		setupDOM: function(res) {
-			var domEv = res[0],
-			    uiClass = res[1],
-			    rpcClass = res[2],
-			    formClass = res[3],
-			    rpcBaseURL = res[4];
-
-			rpcClass.setBaseURL(rpcBaseURL);
-
-			rpcClass.addInterceptor(function(msg, req) {
-				if (!L.isObject(msg) || !L.isObject(msg.error) || msg.error.code != -32002)
-					return;
-
-				if (!L.isObject(req) || (req.object == 'session' && req.method == 'access'))
-					return;
-
-				return rpcClass.declare({
-					'object': 'session',
-					'method': 'access',
-					'params': [ 'scope', 'object', 'function' ],
-					'expect': { access: true }
-				})('uci', 'luci', 'read').catch(L.notifySessionExpiry);
-			});
-
-			Request.addInterceptor(function(res) {
-				var isDenied = false;
-
-				if (res.status == 403 && res.headers.get('X-LuCI-Login-Required') == 'yes')
-					isDenied = true;
-
-				if (!isDenied)
-					return;
-
-				L.notifySessionExpiry();
-			});
-
-			return this.probeSystemFeatures().finally(this.initDOM);
-		},
-
-		/* private */
-		initDOM: function() {
-			originalCBIInit();
-			Poll.start();
-			document.dispatchEvent(new CustomEvent('luci-loaded'));
-		},
-
-		/**
-		 * The `env` object holds environment settings used by LuCI, such
-		 * as request timeouts, base URLs etc.
-		 *
-		 * @instance
-		 * @memberof LuCI
-		 */
-		env: {},
-
-		/**
-		 * Construct a relative URL path from the given prefix and parts.
-		 * The resulting URL is guaranteed to only contain the characters
-		 * `a-z`, `A-Z`, `0-9`, `_`, `.`, `%`, `,`, `;`, and `-` as well
-		 * as `/` for the path separator.
-		 *
-		 * @instance
-		 * @memberof LuCI
-		 *
-		 * @param {string} [prefix]
-		 * The prefix to join the given parts with. If the `prefix` is
-		 * omitted, it defaults to an empty string.
-		 *
-		 * @param {string[]} [parts]
-		 * An array of parts to join into an URL path. Parts may contain
-		 * slashes and any of the other characters mentioned above.
-		 *
-		 * @return {string}
-		 * Return the joined URL path.
-		 */
-		path: function(prefix, parts) {
-			var url = [ prefix || '' ];
-
-			for (var i = 0; i < parts.length; i++)
-				if (/^(?:[a-zA-Z0-9_.%,;-]+\/)*[a-zA-Z0-9_.%,;-]+$/.test(parts[i]))
-					url.push('/', parts[i]);
-
-			if (url.length === 1)
-				url.push('/');
-
-			return url.join('');
-		},
-
-		/**
-		 * Construct an URL  pathrelative to the script path of the server
-		 * side LuCI application (usually `/cgi-bin/luci`).
-		 *
-		 * The resulting URL is guaranteed to only contain the characters
-		 * `a-z`, `A-Z`, `0-9`, `_`, `.`, `%`, `,`, `;`, and `-` as well
-		 * as `/` for the path separator.
-		 *
-		 * @instance
-		 * @memberof LuCI
-		 *
-		 * @param {string[]} [parts]
-		 * An array of parts to join into an URL path. Parts may contain
-		 * slashes and any of the other characters mentioned above.
-		 *
-		 * @return {string}
-		 * Returns the resulting URL path.
-		 */
-		url: function() {
-			return this.path(this.env.scriptname, arguments);
-		},
-
-		/**
-		 * Construct an URL path relative to the global static resource path
-		 * of the LuCI ui (usually `/luci-static/resources`).
-		 *
-		 * The resulting URL is guaranteed to only contain the characters
-		 * `a-z`, `A-Z`, `0-9`, `_`, `.`, `%`, `,`, `;`, and `-` as well
-		 * as `/` for the path separator.
-		 *
-		 * @instance
-		 * @memberof LuCI
-		 *
-		 * @param {string[]} [parts]
-		 * An array of parts to join into an URL path. Parts may contain
-		 * slashes and any of the other characters mentioned above.
-		 *
-		 * @return {string}
-		 * Returns the resulting URL path.
-		 */
-		resource: function() {
-			return this.path(this.env.resource, arguments);
-		},
-
-		/**
-		 * Return the complete URL path to the current view.
-		 *
-		 * @instance
-		 * @memberof LuCI
-		 *
-		 * @return {string}
-		 * Returns the URL path to the current view.
-		 */
-		location: function() {
-			return this.path(this.env.scriptname, this.env.requestpath);
-		},
-
-
-		/**
-		 * Tests whether the passed argument is a JavaScript object.
-		 * This function is meant to be an object counterpart to the
-		 * standard `Array.isArray()` function.
-		 *
-		 * @instance
-		 * @memberof LuCI
-		 *
-		 * @param {*} [val]
-		 * The value to test
-		 *
-		 * @return {boolean}
-		 * Returns `true` if the given value is of type object and
-		 * not `null`, else returns `false`.
-		 */
-		isObject: function(val) {
-			return (val != null && typeof(val) == 'object');
-		},
-
-		/**
-		 * Return an array of sorted object keys, optionally sorted by
-		 * a different key or a different sorting mode.
-		 *
-		 * @instance
-		 * @memberof LuCI
-		 *
-		 * @param {object} obj
-		 * The object to extract the keys from. If the given value is
-		 * not an object, the function will return an empty array.
-		 *
-		 * @param {string} [key]
-		 * Specifies the key to order by. This is mainly useful for
-		 * nested objects of objects or objects of arrays when sorting
-		 * shall not be performed by the primary object keys but by
-		 * some other key pointing to a value within the nested values.
-		 *
-		 * @param {string} [sortmode]
-		 * May be either `addr` or `num` to override the natural
-		 * lexicographic sorting with a sorting suitable for IP/MAC style
-		 * addresses or numeric values respectively.
-		 *
-		 * @return {string[]}
-		 * Returns an array containing the sorted keys of the given object.
-		 */
-		sortedKeys: function(obj, key, sortmode) {
-			if (obj == null || typeof(obj) != 'object')
-				return [];
-
-			return Object.keys(obj).map(function(e) {
-				var v = (key != null) ? obj[e][key] : e;
-
-				switch (sortmode) {
-				case 'addr':
-					v = (v != null) ? v.replace(/(?:^|[.:])([0-9a-fA-F]{1,4})/g,
-						function(m0, m1) { return ('000' + m1.toLowerCase()).substr(-4) }) : null;
-					break;
-
-				case 'num':
-					v = (v != null) ? +v : null;
-					break;
-				}
-
-				return [ e, v ];
-			}).filter(function(e) {
-				return (e[1] != null);
-			}).sort(function(a, b) {
-				return (a[1] > b[1]);
-			}).map(function(e) {
-				return e[0];
-			});
-		},
-
-		/**
-		 * Converts the given value to an array. If the given value is of
-		 * type array, it is returned as-is, values of type object are
-		 * returned as one-element array containing the object, empty
-		 * strings and `null` values are returned as empty array, all other
-		 * values are converted using `String()`, trimmed, split on white
-		 * space and returned as array.
-		 *
-		 * @instance
-		 * @memberof LuCI
-		 *
-		 * @param {*} val
-		 * The value to convert into an array.
-		 *
-		 * @return {Array<*>}
-		 * Returns the resulting array.
-		 */
-		toArray: function(val) {
-			if (val == null)
-				return [];
-			else if (Array.isArray(val))
-				return val;
-			else if (typeof(val) == 'object')
-				return [ val ];
-
-			var s = String(val).trim();
-
-			if (s == '')
-				return [];
-
-			return s.split(/\s+/);
-		},
-
-		/**
-		 * Returns a promise resolving with either the given value or or with
-		 * the given default in case the input value is a rejecting promise.
-		 *
-		 * @instance
-		 * @memberof LuCI
-		 *
-		 * @param {*} value
-		 * The value to resolve the promise with.
-		 *
-		 * @param {*} defvalue
-		 * The default value to resolve the promise with in case the given
-		 * input value is a rejecting promise.
-		 *
-		 * @returns {Promise<*>}
-		 * Returns a new promise resolving either to the given input value or
-		 * to the given default value on error.
-		 */
-		resolveDefault: function(value, defvalue) {
-			return Promise.resolve(value).catch(function() { return defvalue });
-		},
-
-		/**
-		 * The request callback function is invoked whenever an HTTP
-		 * reply to a request made using the `L.get()`, `L.post()` or
-		 * `L.poll()` function is timed out or received successfully.
-		 *
-		 * @instance
-		 * @memberof LuCI
-		 *
-		 * @callback LuCI.requestCallbackFn
-		 * @param {XMLHTTPRequest} xhr
-		 * The XMLHTTPRequest instance used to make the request.
-		 *
-		 * @param {*} data
-		 * The response JSON if the response could be parsed as such,
-		 * else `null`.
-		 *
-		 * @param {number} duration
-		 * The total duration of the request in milliseconds.
-		 */
-
-		/**
-		 * Issues a GET request to the given url and invokes the specified
-		 * callback function. The function is a wrapper around
-		 * {@link LuCI.Request#request Request.request()}.
-		 *
-		 * @deprecated
-		 * @instance
-		 * @memberof LuCI
-		 *
-		 * @param {string} url
-		 * The URL to request.
-		 *
-		 * @param {Object<string, string>} [args]
-		 * Additional query string arguments to append to the URL.
-		 *
-		 * @param {LuCI.requestCallbackFn} cb
-		 * The callback function to invoke when the request finishes.
-		 *
-		 * @return {Promise<null>}
-		 * Returns a promise resolving to `null` when concluded.
-		 */
-		get: function(url, args, cb) {
-			return this.poll(null, url, args, cb, false);
-		},
-
-		/**
-		 * Issues a POST request to the given url and invokes the specified
-		 * callback function. The function is a wrapper around
-		 * {@link LuCI.Request#request Request.request()}. The request is
-		 * sent using `application/x-www-form-urlencoded` encoding and will
-		 * contain a field `token` with the current value of `LuCI.env.token`
-		 * by default.
-		 *
-		 * @deprecated
-		 * @instance
-		 * @memberof LuCI
-		 *
-		 * @param {string} url
-		 * The URL to request.
-		 *
-		 * @param {Object<string, string>} [args]
-		 * Additional post arguments to append to the request body.
-		 *
-		 * @param {LuCI.requestCallbackFn} cb
-		 * The callback function to invoke when the request finishes.
-		 *
-		 * @return {Promise<null>}
-		 * Returns a promise resolving to `null` when concluded.
-		 */
-		post: function(url, args, cb) {
-			return this.poll(null, url, args, cb, true);
-		},
-
-		/**
-		 * Register a polling HTTP request that invokes the specified
-		 * callback function. The function is a wrapper around
-		 * {@link LuCI.Request.poll#add Request.poll.add()}.
-		 *
-		 * @deprecated
-		 * @instance
-		 * @memberof LuCI
-		 *
-		 * @param {number} interval
-		 * The poll interval to use. If set to a value less than or equal
-		 * to `0`, it will default to the global poll interval configured
-		 * in `LuCI.env.pollinterval`.
-		 *
-		 * @param {string} url
-		 * The URL to request.
-		 *
-		 * @param {Object<string, string>} [args]
-		 * Specifies additional arguments for the request. For GET requests,
-		 * the arguments are appended to the URL as query string, for POST
-		 * requests, they'll be added to the request body.
-		 *
-		 * @param {LuCI.requestCallbackFn} cb
-		 * The callback function to invoke whenever a request finishes.
-		 *
-		 * @param {boolean} [post=false]
-		 * When set to `false` or not specified, poll requests will be made
-		 * using the GET method. When set to `true`, POST requests will be
-		 * issued. In case of POST requests, the request body will contain
-		 * an argument `token` with the current value of `LuCI.env.token` by
-		 * default, regardless of the parameters specified with `args`.
-		 *
-		 * @return {function}
-		 * Returns the internally created function that has been passed to
-		 * {@link LuCI.Request.poll#add Request.poll.add()}. This value can
-		 * be passed to {@link LuCI.Poll.remove Poll.remove()} to remove the
-		 * polling request.
-		 */
-		poll: function(interval, url, args, cb, post) {
-			if (interval !== null && interval <= 0)
-				interval = this.env.pollinterval;
-
-			var data = post ? { token: this.env.token } : null,
-			    method = post ? 'POST' : 'GET';
-
-			if (!/^(?:\/|\S+:\/\/)/.test(url))
-				url = this.url(url);
-
-			if (args != null)
-				data = Object.assign(data || {}, args);
-
-			if (interval !== null)
-				return Request.poll.add(interval, url, { method: method, query: data }, cb);
-			else
-				return Request.request(url, { method: method, query: data })
-					.then(function(res) {
-						var json = null;
-						if (/^application\/json\b/.test(res.headers.get('Content-Type')))
-							try { json = res.json() } catch(e) {}
-						cb(res.xhr, json, res.duration);
-					});
-		},
-
-		/**
-		 * Deprecated wrapper around {@link LuCI.Poll.remove Poll.remove()}.
-		 *
-		 * @deprecated
-		 * @instance
-		 * @memberof LuCI
-		 *
-		 * @param {function} entry
-		 * The polling function to remove.
-		 *
-		 * @return {boolean}
-		 * Returns `true` when the function has been removed or `false` if
-		 * it could not be found.
-		 */
-		stop: function(entry) { return Poll.remove(entry) },
-
-		/**
-		 * Deprecated wrapper around {@link LuCI.Poll.stop Poll.stop()}.
-		 *
-		 * @deprecated
-		 * @instance
-		 * @memberof LuCI
-		 *
-		 * @return {boolean}
-		 * Returns `true` when the polling loop has been stopped or `false`
-		 * when it didn't run to begin with.
-		 */
-		halt: function() { return Poll.stop() },
-
-		/**
-		 * Deprecated wrapper around {@link LuCI.Poll.start Poll.start()}.
-		 *
-		 * @deprecated
-		 * @instance
-		 * @memberof LuCI
-		 *
-		 * @return {boolean}
-		 * Returns `true` when the polling loop has been started or `false`
-		 * when it was already running.
-		 */
-		run: function() { return Poll.start() },
-
-
-		/**
-		 * @class
-		 * @memberof LuCI
-		 * @hideconstructor
-		 * @classdesc
-		 *
-		 * The `dom` class provides convenience method for creating and
-		 * manipulating DOM elements.
-		 */
-		dom: Class.singleton(/* @lends LuCI.dom.prototype */ {
-			__name__: 'LuCI.DOM',
-
-			/**
-			 * Tests whether the given argument is a valid DOM `Node`.
-			 *
-			 * @instance
-			 * @memberof LuCI.dom
-			 * @param {*} e
-			 * The value to test.
-			 *
-			 * @returns {boolean}
-			 * Returns `true` if the value is a DOM `Node`, else `false`.
-			 */
-			elem: function(e) {
-				return (e != null && typeof(e) == 'object' && 'nodeType' in e);
-			},
-
-			/**
-			 * Parses a given string as HTML and returns the first child node.
-			 *
-			 * @instance
-			 * @memberof LuCI.dom
-			 * @param {string} s
-			 * A string containing an HTML fragment to parse. Note that only
-			 * the first result of the resulting structure is returned, so an
-			 * input value of `<div>foo</div> <div>bar</div>` will only return
-			 * the first `div` element node.
-			 *
-			 * @returns {Node}
-			 * Returns the first DOM `Node` extracted from the HTML fragment or
-			 * `null` on parsing failures or if no element could be found.
-			 */
-			parse: function(s) {
-				var elem;
-
-				try {
-					domParser = domParser || new DOMParser();
-					elem = domParser.parseFromString(s, 'text/html').body.firstChild;
-				}
-				catch(e) {}
-
-				if (!elem) {
-					try {
-						dummyElem = dummyElem || document.createElement('div');
-						dummyElem.innerHTML = s;
-						elem = dummyElem.firstChild;
-					}
-					catch (e) {}
-				}
-
-				return elem || null;
-			},
-
-			/**
-			 * Tests whether a given `Node` matches the given query selector.
-			 *
-			 * This function is a convenience wrapper around the standard
-			 * `Node.matches("selector")` function with the added benefit that
-			 * the `node` argument may be a non-`Node` value, in which case
-			 * this function simply returns `false`.
-			 *
-			 * @instance
-			 * @memberof LuCI.dom
-			 * @param {*} node
-			 * The `Node` argument to test the selector against.
-			 *
-			 * @param {string} [selector]
-			 * The query selector expression to test against the given node.
-			 *
-			 * @returns {boolean}
-			 * Returns `true` if the given node matches the specified selector
-			 * or `false` when the node argument is no valid DOM `Node` or the
-			 * selector didn't match.
-			 */
-			matches: function(node, selector) {
-				var m = this.elem(node) ? node.matches || node.msMatchesSelector : null;
-				return m ? m.call(node, selector) : false;
-			},
-
-			/**
-			 * Returns the closest parent node that matches the given query
-			 * selector expression.
-			 *
-			 * This function is a convenience wrapper around the standard
-			 * `Node.closest("selector")` function with the added benefit that
-			 * the `node` argument may be a non-`Node` value, in which case
-			 * this function simply returns `null`.
-			 *
-			 * @instance
-			 * @memberof LuCI.dom
-			 * @param {*} node
-			 * The `Node` argument to find the closest parent for.
-			 *
-			 * @param {string} [selector]
-			 * The query selector expression to test against each parent.
-			 *
-			 * @returns {Node|null}
-			 * Returns the closest parent node matching the selector or
-			 * `null` when the node argument is no valid DOM `Node` or the
-			 * selector didn't match any parent.
-			 */
-			parent: function(node, selector) {
-				if (this.elem(node) && node.closest)
-					return node.closest(selector);
-
-				while (this.elem(node))
-					if (this.matches(node, selector))
-						return node;
-					else
-						node = node.parentNode;
-
-				return null;
-			},
-
-			/**
-			 * Appends the given children data to the given node.
-			 *
-			 * @instance
-			 * @memberof LuCI.dom
-			 * @param {*} node
-			 * The `Node` argument to append the children to.
-			 *
-			 * @param {*} [children]
-			 * The childrens to append to the given node.
-			 *
-			 * When `children` is an array, then each item of the array
-			 * will be either appended as child element or text node,
-			 * depending on whether the item is a DOM `Node` instance or
-			 * some other non-`null` value. Non-`Node`, non-`null` values
-			 * will be converted to strings first before being passed as
-			 * argument to `createTextNode()`.
-			 *
-			 * When `children` is a function, it will be invoked with
-			 * the passed `node` argument as sole parameter and the `append`
-			 * function will be invoked again, with the given `node` argument
-			 * as first and the return value of the `children` function as
-			 * second parameter.
-			 *
-			 * When `children` is is a DOM `Node` instance, it will be
-			 * appended to the given `node`.
-			 *
-			 * When `children` is any other non-`null` value, it will be
-			 * converted to a string and appened to the `innerHTML` property
-			 * of the given `node`.
-			 *
-			 * @returns {Node|null}
-			 * Returns the last children `Node` appended to the node or `null`
-			 * if either the `node` argument was no valid DOM `node` or if the
-			 * `children` was `null` or didn't result in further DOM nodes.
-			 */
-			append: function(node, children) {
-				if (!this.elem(node))
-					return null;
-
-				if (Array.isArray(children)) {
-					for (var i = 0; i < children.length; i++)
-						if (this.elem(children[i]))
-							node.appendChild(children[i]);
-						else if (children !== null && children !== undefined)
-							node.appendChild(document.createTextNode('' + children[i]));
-
-					return node.lastChild;
-				}
-				else if (typeof(children) === 'function') {
-					return this.append(node, children(node));
-				}
-				else if (this.elem(children)) {
-					return node.appendChild(children);
-				}
-				else if (children !== null && children !== undefined) {
-					node.innerHTML = '' + children;
-					return node.lastChild;
-				}
-
-				return null;
-			},
-
-			/**
-			 * Replaces the content of the given node with the given children.
-			 *
-			 * This function first removes any children of the given DOM
-			 * `Node` and then adds the given given children following the
-			 * rules outlined below.
-			 *
-			 * @instance
-			 * @memberof LuCI.dom
-			 * @param {*} node
-			 * The `Node` argument to replace the children of.
-			 *
-			 * @param {*} [children]
-			 * The childrens to replace into the given node.
-			 *
-			 * When `children` is an array, then each item of the array
-			 * will be either appended as child element or text node,
-			 * depending on whether the item is a DOM `Node` instance or
-			 * some other non-`null` value. Non-`Node`, non-`null` values
-			 * will be converted to strings first before being passed as
-			 * argument to `createTextNode()`.
-			 *
-			 * When `children` is a function, it will be invoked with
-			 * the passed `node` argument as sole parameter and the `append`
-			 * function will be invoked again, with the given `node` argument
-			 * as first and the return value of the `children` function as
-			 * second parameter.
-			 *
-			 * When `children` is is a DOM `Node` instance, it will be
-			 * appended to the given `node`.
-			 *
-			 * When `children` is any other non-`null` value, it will be
-			 * converted to a string and appened to the `innerHTML` property
-			 * of the given `node`.
-			 *
-			 * @returns {Node|null}
-			 * Returns the last children `Node` appended to the node or `null`
-			 * if either the `node` argument was no valid DOM `node` or if the
-			 * `children` was `null` or didn't result in further DOM nodes.
-			 */
-			content: function(node, children) {
-				if (!this.elem(node))
-					return null;
-
-				var dataNodes = node.querySelectorAll('[data-idref]');
-
-				for (var i = 0; i < dataNodes.length; i++)
-					delete this.registry[dataNodes[i].getAttribute('data-idref')];
-
-				while (node.firstChild)
-					node.removeChild(node.firstChild);
-
-				return this.append(node, children);
-			},
-
-			/**
-			 * Sets attributes or registers event listeners on element nodes.
-			 *
-			 * @instance
-			 * @memberof LuCI.dom
-			 * @param {*} node
-			 * The `Node` argument to set the attributes or add the event
-			 * listeners for. When the given `node` value is not a valid
-			 * DOM `Node`, the function returns and does nothing.
-			 *
-			 * @param {string|Object<string, *>} key
-			 * Specifies either the attribute or event handler name to use,
-			 * or an object containing multiple key, value pairs which are
-			 * each added to the node as either attribute or event handler,
-			 * depending on the respective value.
-			 *
-			 * @param {*} [val]
-			 * Specifies the attribute value or event handler function to add.
-			 * If the `key` parameter is an `Object`, this parameter will be
-			 * ignored.
-			 *
-			 * When `val` is of type function, it will be registered as event
-			 * handler on the given `node` with the `key` parameter being the
-			 * event name.
-			 *
-			 * When `val` is of type object, it will be serialized as JSON and
-			 * added as attribute to the given `node`, using the given `key`
-			 * as attribute name.
-			 *
-			 * When `val` is of any other type, it will be added as attribute
-			 * to the given `node` as-is, with the underlying `setAttribute()`
-			 * call implicitely turning it into a string.
-			 */
-			attr: function(node, key, val) {
-				if (!this.elem(node))
-					return null;
-
-				var attr = null;
-
-				if (typeof(key) === 'object' && key !== null)
-					attr = key;
-				else if (typeof(key) === 'string')
-					attr = {}, attr[key] = val;
-
-				for (key in attr) {
-					if (!attr.hasOwnProperty(key) || attr[key] == null)
-						continue;
-
-					switch (typeof(attr[key])) {
-					case 'function':
-						node.addEventListener(key, attr[key]);
-						break;
-
-					case 'object':
-						node.setAttribute(key, JSON.stringify(attr[key]));
-						break;
-
-					default:
-						node.setAttribute(key, attr[key]);
-					}
-				}
-			},
-
-			/**
-			 * Creates a new DOM `Node` from the given `html`, `attr` and
-			 * `data` parameters.
-			 *
-			 * This function has multiple signatures, it can be either invoked
-			 * in the form `create(html[, attr[, data]])` or in the form
-			 * `create(html[, data])`. The used variant is determined from the
-			 * type of the second argument.
-			 *
-			 * @instance
-			 * @memberof LuCI.dom
-			 * @param {*} html
-			 * Describes the node to create.
-			 *
-			 * When the value of `html` is of type array, a `DocumentFragment`
-			 * node is created and each item of the array is first converted
-			 * to a DOM `Node` by passing it through `create()` and then added
-			 * as child to the fragment.
-			 *
-			 * When the value of `html` is a DOM `Node` instance, no new
-			 * element will be created but the node will be used as-is.
-			 *
-			 * When the value of `html` is a string starting with `<`, it will
-			 * be passed to `dom.parse()` and the resulting value is used.
-			 *
-			 * When the value of `html` is any other string, it will be passed
-			 * to `document.createElement()` for creating a new DOM `Node` of
-			 * the given name.
-			 *
-			 * @param {Object<string, *>} [attr]
-			 * Specifies an Object of key, value pairs to set as attributes
-			 * or event handlers on the created node. Refer to
-			 * {@link LuCI.dom#attr dom.attr()} for details.
-			 *
-			 * @param {*} [data]
-			 * Specifies children to append to the newly created element.
-			 * Refer to {@link LuCI.dom#append dom.append()} for details.
-			 *
-			 * @throws {InvalidCharacterError}
-			 * Throws an `InvalidCharacterError` when the given `html`
-			 * argument contained malformed markup (such as not escaped
-			 * `&` characters in XHTML mode) or when the given node name
-			 * in `html` contains characters which are not legal in DOM
-			 * element names, such as spaces.
-			 *
-			 * @returns {Node}
-			 * Returns the newly created `Node`.
-			 */
-			create: function() {
-				var html = arguments[0],
-				    attr = arguments[1],
-				    data = arguments[2],
-				    elem;
-
-				if (!(attr instanceof Object) || Array.isArray(attr))
-					data = attr, attr = null;
-
-				if (Array.isArray(html)) {
-					elem = document.createDocumentFragment();
-					for (var i = 0; i < html.length; i++)
-						elem.appendChild(this.create(html[i]));
-				}
-				else if (this.elem(html)) {
-					elem = html;
-				}
-				else if (html.charCodeAt(0) === 60) {
-					elem = this.parse(html);
-				}
-				else {
-					elem = document.createElement(html);
-				}
-
-				if (!elem)
-					return null;
-
-				this.attr(elem, attr);
-				this.append(elem, data);
-
-				return elem;
-			},
-
-			registry: {},
-
-			/**
-			 * Attaches or detaches arbitrary data to and from a DOM `Node`.
-			 *
-			 * This function is useful to attach non-string values or runtime
-			 * data that is not serializable to DOM nodes. To decouple data
-			 * from the DOM, values are not added directly to nodes, but
-			 * inserted into a registry instead which is then referenced by a
-			 * string key stored as `data-idref` attribute in the node.
-			 *
-			 * This function has multiple signatures and is sensitive to the
-			 * number of arguments passed to it.
-			 *
-			 *  - `dom.data(node)` -
-			 *     Fetches all data associated with the given node.
-			 *  - `dom.data(node, key)` -
-			 *     Fetches a specific key associated with the given node.
-			 *  - `dom.data(node, key, val)` -
-			 *     Sets a specific key to the given value associated with the
-			 *     given node.
-			 *  - `dom.data(node, null)` -
-			 *     Clears any data associated with the node.
-			 *  - `dom.data(node, key, null)` -
-			 *     Clears the given key associated with the node.
-			 *
-			 * @instance
-			 * @memberof LuCI.dom
-			 * @param {Node} node
-			 * The DOM `Node` instance to set or retrieve the data for.
-			 *
-			 * @param {string|null} [key]
-			 * This is either a string specifying the key to retrieve, or
-			 * `null` to unset the entire node data.
-			 *
-			 * @param {*|null} [val]
-			 * This is either a non-`null` value to set for a given key or
-			 * `null` to remove the given `key` from the specified node.
-			 *
-			 * @returns {*}
-			 * Returns the get or set value, or `null` when no value could
-			 * be found.
-			 */
-			data: function(node, key, val) {
-				var id = node.getAttribute('data-idref');
-
-				/* clear all data */
-				if (arguments.length > 1 && key == null) {
-					if (id != null) {
-						node.removeAttribute('data-idref');
-						val = this.registry[id]
-						delete this.registry[id];
-						return val;
-					}
-
-					return null;
-				}
-
-				/* clear a key */
-				else if (arguments.length > 2 && key != null && val == null) {
-					if (id != null) {
-						val = this.registry[id][key];
-						delete this.registry[id][key];
-						return val;
-					}
-
-					return null;
-				}
-
-				/* set a key */
-				else if (arguments.length > 2 && key != null && val != null) {
-					if (id == null) {
-						do { id = Math.floor(Math.random() * 0xffffffff).toString(16) }
-						while (this.registry.hasOwnProperty(id));
-
-						node.setAttribute('data-idref', id);
-						this.registry[id] = {};
-					}
-
-					return (this.registry[id][key] = val);
-				}
-
-				/* get all data */
-				else if (arguments.length == 1) {
-					if (id != null)
-						return this.registry[id];
-
-					return null;
-				}
-
-				/* get a key */
-				else if (arguments.length == 2) {
-					if (id != null)
-						return this.registry[id][key];
-				}
-
-				return null;
-			},
-
-			/**
-			 * Binds the given class instance ot the specified DOM `Node`.
-			 *
-			 * This function uses the `dom.data()` facility to attach the
-			 * passed instance of a Class to a node. This is needed for
-			 * complex widget elements or similar where the corresponding
-			 * class instance responsible for the element must be retrieved
-			 * from DOM nodes obtained by `querySelector()` or similar means.
-			 *
-			 * @instance
-			 * @memberof LuCI.dom
-			 * @param {Node} node
-			 * The DOM `Node` instance to bind the class to.
-			 *
-			 * @param {Class} inst
-			 * The Class instance to bind to the node.
-			 *
-			 * @throws {TypeError}
-			 * Throws a `TypeError` when the given instance argument isn't
-			 * a valid Class instance.
-			 *
-			 * @returns {Class}
-			 * Returns the bound class instance.
-			 */
-			bindClassInstance: function(node, inst) {
-				if (!(inst instanceof Class))
-					L.error('TypeError', 'Argument must be a class instance');
-
-				return this.data(node, '_class', inst);
-			},
-
-			/**
-			 * Finds a bound class instance on the given node itself or the
-			 * first bound instance on its closest parent node.
-			 *
-			 * @instance
-			 * @memberof LuCI.dom
-			 * @param {Node} node
-			 * The DOM `Node` instance to start from.
-			 *
-			 * @returns {Class|null}
-			 * Returns the founds class instance if any or `null` if no bound
-			 * class could be found on the node itself or any of its parents.
-			 */
-			findClassInstance: function(node) {
-				var inst = null;
-
-				do {
-					inst = this.data(node, '_class');
-					node = node.parentNode;
-				}
-				while (!(inst instanceof Class) && node != null);
-
-				return inst;
-			},
-
-			/**
-			 * Finds a bound class instance on the given node itself or the
-			 * first bound instance on its closest parent node and invokes
-			 * the specified method name on the found class instance.
-			 *
-			 * @instance
-			 * @memberof LuCI.dom
-			 * @param {Node} node
-			 * The DOM `Node` instance to start from.
-			 *
-			 * @param {string} method
-			 * The name of the method to invoke on the found class instance.
-			 *
-			 * @param {...*} params
-			 * Additional arguments to pass to the invoked method as-is.
-			 *
-			 * @returns {*|null}
-			 * Returns the return value of the invoked method if a class
-			 * instance and method has been found. Returns `null` if either
-			 * no bound class instance could be found, or if the found
-			 * instance didn't have the requested `method`.
-			 */
-			callClassMethod: function(node, method /*, ... */) {
-				var inst = this.findClassInstance(node);
-
-				if (inst == null || typeof(inst[method]) != 'function')
-					return null;
-
-				return inst[method].apply(inst, inst.varargs(arguments, 2));
-			},
-
-			/**
-			 * The ignore callback function is invoked by `isEmpty()` for each
-			 * child node to decide whether to ignore a child node or not.
-			 *
-			 * When this function returns `false`, the node passed to it is
-			 * ignored, else not.
-			 *
-			 * @callback LuCI.dom~ignoreCallbackFn
-			 * @param {Node} node
-			 * The child node to test.
-			 *
-			 * @returns {boolean}
-			 * Boolean indicating whether to ignore the node or not.
-			 */
-
-			/**
-			 * Tests whether a given DOM `Node` instance is empty or appears
-			 * empty.
-			 *
-			 * Any element child nodes which have the CSS class `hidden` set
-			 * or for which the optionally passed `ignoreFn` callback function
-			 * returns `false` are ignored.
-			 *
-			 * @instance
-			 * @memberof LuCI.dom
-			 * @param {Node} node
-			 * The DOM `Node` instance to test.
-			 *
-			 * @param {LuCI.dom~ignoreCallbackFn} [ignoreFn]
-			 * Specifies an optional function which is invoked for each child
-			 * node to decide whether the child node should be ignored or not.
-			 *
-			 * @returns {boolean}
-			 * Returns `true` if the node does not have any children or if
-			 * any children node either has a `hidden` CSS class or a `false`
-			 * result when testing it using the given `ignoreFn`.
-			 */
-			isEmpty: function(node, ignoreFn) {
-				for (var child = node.firstElementChild; child != null; child = child.nextElementSibling)
-					if (!child.classList.contains('hidden') && (!ignoreFn || !ignoreFn(child)))
-						return false;
-
-				return true;
-			}
-		}),
-
-		Poll: Poll,
-		Class: Class,
-		Request: Request,
-
-		/**
-		 * @class
-		 * @memberof LuCI
-		 * @hideconstructor
-		 * @classdesc
-		 *
-		 * The `view` class forms the basis of views and provides a standard
-		 * set of methods to inherit from.
-		 */
-		view: Class.extend(/* @lends LuCI.view.prototype */ {
-			__name__: 'LuCI.View',
-
-			__init__: function() {
-				var vp = document.getElementById('view');
-
-				L.dom.content(vp, E('div', { 'class': 'spinning' }, _('Loading view…')));
-
-				return Promise.resolve(this.load())
-					.then(L.bind(this.render, this))
-					.then(L.bind(function(nodes) {
-						var vp = document.getElementById('view');
-
-						L.dom.content(vp, nodes);
-						L.dom.append(vp, this.addFooter());
-					}, this)).catch(L.error);
-			},
-
-			/**
-			 * The load function is invoked before the view is rendered.
-			 *
-			 * The invocation of this function is wrapped by
-			 * `Promise.resolve()` so it may return Promises if needed.
-			 *
-			 * The return value of the function (or the resolved values
-			 * of the promise returned by it) will be passed as first
-			 * argument to `render()`.
-			 *
-			 * This function is supposed to be overwritten by subclasses,
-			 * the default implementation does nothing.
-			 *
-			 * @instance
-			 * @abstract
-			 * @memberof LuCI.view
-			 *
-			 * @returns {*|Promise<*>}
-			 * May return any value or a Promise resolving to any value.
-			 */
-			load: function() {},
-
-			/**
-			 * The render function is invoked after the
-			 * {@link LuCI.view#load load()} function and responsible
-			 * for setting up the view contents. It must return a DOM
-			 * `Node` or `DocumentFragment` holding the contents to
-			 * insert into the view area.
-			 *
-			 * The invocation of this function is wrapped by
-			 * `Promise.resolve()` so it may return Promises if needed.
-			 *
-			 * The return value of the function (or the resolved values
-			 * of the promise returned by it) will be inserted into the
-			 * main content area using
-			 * {@link LuCI.dom#append dom.append()}.
-			 *
-			 * This function is supposed to be overwritten by subclasses,
-			 * the default implementation does nothing.
-			 *
-			 * @instance
-			 * @abstract
-			 * @memberof LuCI.view
-			 * @param {*|null} load_results
-			 * This function will receive the return value of the
-			 * {@link LuCI.view#load view.load()} function as first
-			 * argument.
-			 *
-			 * @returns {Node|Promise<Node>}
-			 * Should return a DOM `Node` value or a `Promise` resolving
-			 * to a `Node` value.
-			 */
-			render: function() {},
-
-			/**
-			 * The handleSave function is invoked when the user clicks
-			 * the `Save` button in the page action footer.
-			 *
-			 * The default implementation should be sufficient for most
-			 * views using {@link form#Map form.Map()} based forms - it
-			 * will iterate all forms present in the view and invoke
-			 * the {@link form#Map#save Map.save()} method on each form.
-			 *
-			 * Views not using `Map` instances or requiring other special
-			 * logic should overwrite `handleSave()` with a custom
-			 * implementation.
-			 *
-			 * To disable the `Save` page footer button, views extending
-			 * this base class should overwrite the `handleSave` function
-			 * with `null`.
-			 *
-			 * The invocation of this function is wrapped by
-			 * `Promise.resolve()` so it may return Promises if needed.
-			 *
-			 * @instance
-			 * @memberof LuCI.view
-			 * @param {Event} ev
-			 * The DOM event that triggered the function.
-			 *
-			 * @returns {*|Promise<*>}
-			 * Any return values of this function are discarded, but
-			 * passed through `Promise.resolve()` to ensure that any
-			 * returned promise runs to completion before the button
-			 * is reenabled.
-			 */
-			handleSave: function(ev) {
-				var tasks = [];
-
-				document.getElementById('maincontent')
-					.querySelectorAll('.cbi-map').forEach(function(map) {
-						tasks.push(L.dom.callClassMethod(map, 'save'));
-					});
-
-				return Promise.all(tasks);
-			},
-
-			/**
-			 * The handleSaveApply function is invoked when the user clicks
-			 * the `Save & Apply` button in the page action footer.
-			 *
-			 * The default implementation should be sufficient for most
-			 * views using {@link form#Map form.Map()} based forms - it
-			 * will first invoke
-			 * {@link LuCI.view.handleSave view.handleSave()} and then
-			 * call {@link ui#changes#apply ui.changes.apply()} to start the
-			 * modal config apply and page reload flow.
-			 *
-			 * Views not using `Map` instances or requiring other special
-			 * logic should overwrite `handleSaveApply()` with a custom
-			 * implementation.
-			 *
-			 * To disable the `Save & Apply` page footer button, views
-			 * extending this base class should overwrite the
-			 * `handleSaveApply` function with `null`.
-			 *
-			 * The invocation of this function is wrapped by
-			 * `Promise.resolve()` so it may return Promises if needed.
-			 *
-			 * @instance
-			 * @memberof LuCI.view
-			 * @param {Event} ev
-			 * The DOM event that triggered the function.
-			 *
-			 * @returns {*|Promise<*>}
-			 * Any return values of this function are discarded, but
-			 * passed through `Promise.resolve()` to ensure that any
-			 * returned promise runs to completion before the button
-			 * is reenabled.
-			 */
-			handleSaveApply: function(ev) {
-				return this.handleSave(ev).then(function() {
-					L.ui.changes.apply(true);
-				});
-			},
-
-			/**
-			 * The handleReset function is invoked when the user clicks
-			 * the `Reset` button in the page action footer.
-			 *
-			 * The default implementation should be sufficient for most
-			 * views using {@link form#Map form.Map()} based forms - it
-			 * will iterate all forms present in the view and invoke
-			 * the {@link form#Map#save Map.reset()} method on each form.
-			 *
-			 * Views not using `Map` instances or requiring other special
-			 * logic should overwrite `handleReset()` with a custom
-			 * implementation.
-			 *
-			 * To disable the `Reset` page footer button, views extending
-			 * this base class should overwrite the `handleReset` function
-			 * with `null`.
-			 *
-			 * The invocation of this function is wrapped by
-			 * `Promise.resolve()` so it may return Promises if needed.
-			 *
-			 * @instance
-			 * @memberof LuCI.view
-			 * @param {Event} ev
-			 * The DOM event that triggered the function.
-			 *
-			 * @returns {*|Promise<*>}
-			 * Any return values of this function are discarded, but
-			 * passed through `Promise.resolve()` to ensure that any
-			 * returned promise runs to completion before the button
-			 * is reenabled.
-			 */
-			handleReset: function(ev) {
-				var tasks = [];
-
-				document.getElementById('maincontent')
-					.querySelectorAll('.cbi-map').forEach(function(map) {
-						tasks.push(L.dom.callClassMethod(map, 'reset'));
-					});
-
-				return Promise.all(tasks);
-			},
-
-			/**
-			 * Renders a standard page action footer if any of the
-			 * `handleSave()`, `handleSaveApply()` or `handleReset()`
-			 * functions are defined.
-			 *
-			 * The default implementation should be sufficient for most
-			 * views - it will render a standard page footer with action
-			 * buttons labeled `Save`, `Save & Apply` and `Reset`
-			 * triggering the `handleSave()`, `handleSaveApply()` and
-			 * `handleReset()` functions respectively.
-			 *
-			 * When any of these `handle*()` functions is overwritten
-			 * with `null` by a view extending this class, the
-			 * corresponding button will not be rendered.
-			 *
-			 * @instance
-			 * @memberof LuCI.view
-			 * @returns {DocumentFragment}
-			 * Returns a `DocumentFragment` containing the footer bar
-			 * with buttons for each corresponding `handle*()` action
-			 * or an empty `DocumentFragment` if all three `handle*()`
-			 * methods are overwritten with `null`.
-			 */
-			addFooter: function() {
-				var footer = E([]);
-
-				if (this.handleSaveApply || this.handleSave || this.handleReset) {
-					footer.appendChild(E('div', { 'class': 'cbi-page-actions' }, [
-						this.handleSaveApply ? E('button', {
-							'class': 'cbi-button cbi-button-apply',
-							'click': L.ui.createHandlerFn(this, 'handleSaveApply')
-						}, [ _('Save & Apply') ]) : '', ' ',
-						this.handleSave ? E('button', {
-							'class': 'cbi-button cbi-button-save',
-							'click': L.ui.createHandlerFn(this, 'handleSave')
-						}, [ _('Save') ]) : '', ' ',
-						this.handleReset ? E('button', {
-							'class': 'cbi-button cbi-button-reset',
-							'click': L.ui.createHandlerFn(this, 'handleReset')
-						}, [ _('Reset') ]) : ''
-					]));
-				}
-
-				return footer;
-			}
-		})
-	});
-
-	/**
-	 * @class
-	 * @memberof LuCI
-	 * @deprecated
-	 * @classdesc
-	 *
-	 * The `LuCI.XHR` class is a legacy compatibility shim for the
-	 * functionality formerly provided by `xhr.js`. It is registered as global
-	 * `window.XHR` symbol for compatibility with legacy code.
-	 *
-	 * New code should use {@link LuCI.Request} instead to implement HTTP
-	 * request handling.
-	 */
-	var XHR = Class.extend(/** @lends LuCI.XHR.prototype */ {
-		__name__: 'LuCI.XHR',
-		__init__: function() {
-			if (window.console && console.debug)
-				console.debug('Direct use XHR() is deprecated, please use L.Request instead');
-		},
-
-		_response: function(cb, res, json, duration) {
-			if (this.active)
-				cb(res, json, duration);
-			delete this.active;
-		},
-
-		/**
-		 * This function is a legacy wrapper around
-		 * {@link LuCI#get LuCI.get()}.
-		 *
-		 * @instance
-		 * @deprecated
-		 * @memberof LuCI.XHR
-		 *
-		 * @param {string} url
-		 * The URL to request
-		 *
-		 * @param {Object} [data]
-		 * Additional query string data
-		 *
-		 * @param {LuCI.requestCallbackFn} [callback]
-		 * Callback function to invoke on completion
-		 *
-		 * @param {number} [timeout]
-		 * Request timeout to use
-		 *
-		 * @return {Promise<null>}
-		 */
-		get: function(url, data, callback, timeout) {
-			this.active = true;
-			L.get(url, data, this._response.bind(this, callback), timeout);
-		},
-
-		/**
-		 * This function is a legacy wrapper around
-		 * {@link LuCI#post LuCI.post()}.
-		 *
-		 * @instance
-		 * @deprecated
-		 * @memberof LuCI.XHR
-		 *
-		 * @param {string} url
-		 * The URL to request
-		 *
-		 * @param {Object} [data]
-		 * Additional data to append to the request body.
-		 *
-		 * @param {LuCI.requestCallbackFn} [callback]
-		 * Callback function to invoke on completion
-		 *
-		 * @param {number} [timeout]
-		 * Request timeout to use
-		 *
-		 * @return {Promise<null>}
-		 */
-		post: function(url, data, callback, timeout) {
-			this.active = true;
-			L.post(url, data, this._response.bind(this, callback), timeout);
-		},
-
-		/**
-		 * Cancels a running request.
-		 *
-		 * This function does not actually cancel the underlying
-		 * `XMLHTTPRequest` request but it sets a flag which prevents the
-		 * invocation of the callback function when the request eventually
-		 * finishes or timed out.
-		 *
-		 * @instance
-		 * @deprecated
-		 * @memberof LuCI.XHR
-		 */
-		cancel: function() { delete this.active },
-
-		/**
-		 * Checks the running state of the request.
-		 *
-		 * @instance
-		 * @deprecated
-		 * @memberof LuCI.XHR
-		 *
-		 * @returns {boolean}
-		 * Returns `true` if the request is still running or `false` if it
-		 * already completed.
-		 */
-		busy: function() { return (this.active === true) },
-
-		/**
-		 * Ignored for backwards compatibility.
-		 *
-		 * This function does nothing.
-		 *
-		 * @instance
-		 * @deprecated
-		 * @memberof LuCI.XHR
-		 */
-		abort: function() {},
-
-		/**
-		 * Existing for backwards compatibility.
-		 *
-		 * This function simply throws an `InternalError` when invoked.
-		 *
-		 * @instance
-		 * @deprecated
-		 * @memberof LuCI.XHR
-		 *
-		 * @throws {InternalError}
-		 * Throws an `InternalError` with the message `Not implemented`
-		 * when invoked.
-		 */
-		send_form: function() { L.error('InternalError', 'Not implemented') },
-	});
-
-	XHR.get = function() { return window.L.get.apply(window.L, arguments) };
-	XHR.post = function() { return window.L.post.apply(window.L, arguments) };
-	XHR.poll = function() { return window.L.poll.apply(window.L, arguments) };
-	XHR.stop = Request.poll.remove.bind(Request.poll);
-	XHR.halt = Request.poll.stop.bind(Request.poll);
-	XHR.run = Request.poll.start.bind(Request.poll);
-	XHR.running = Request.poll.active.bind(Request.poll);
-
-	window.XHR = XHR;
-	window.LuCI = LuCI;
-})(window, document);
-