/** * @author Ed Spencer * * Proxies are used by {@link Ext.data.Store Stores} to handle the loading and saving of {@link Ext.data.Model Model} * data. Usually developers will not need to create or interact with proxies directly. * * # Types of Proxy * * There are two main types of Proxy - {@link Ext.data.proxy.Client Client} and {@link Ext.data.proxy.Server Server}. * The Client proxies save their data locally and include the following subclasses: * * - {@link Ext.data.proxy.LocalStorage LocalStorageProxy} - saves its data to localStorage if the browser supports it * - {@link Ext.data.proxy.SessionStorage SessionStorageProxy} - saves its data to sessionStorage if the browsers supports it * - {@link Ext.data.proxy.Memory MemoryProxy} - holds data in memory only, any data is lost when the page is refreshed * * The Server proxies save their data by sending requests to some remote server. These proxies include: * * - {@link Ext.data.proxy.Ajax Ajax} - sends requests to a server on the same domain * - {@link Ext.data.proxy.JsonP JsonP} - uses JSON-P to send requests to a server on a different domain * - {@link Ext.data.proxy.Rest Rest} - uses RESTful HTTP methods (GET/PUT/POST/DELETE) to communicate with server * - {@link Ext.data.proxy.Direct Direct} - uses {@link Ext.direct.Manager} to send requests * * Proxies operate on the principle that all operations performed are either Create, Read, Update or Delete. These four * operations are mapped to the methods {@link #create}, {@link #read}, {@link #update} and {@link #erase} * respectively. Each Proxy subclass implements these functions. * * The CRUD methods each expect an {@link Ext.data.operation.Operation Operation} object as the sole argument. The Operation * encapsulates information about the action the Store wishes to perform, the {@link Ext.data.Model model} instances * that are to be modified, etc. See the {@link Ext.data.operation.Operation Operation} documentation for more details. Each CRUD * method also accepts a callback function to be called asynchronously on completion. * * Proxies also support batching of Operations via a {@link Ext.data.Batch batch} object, invoked by the {@link #batch} * method. */Ext.define('Ext.data.proxy.Proxy', { mixins: [ 'Ext.mixin.Factoryable', 'Ext.mixin.Observable' ], $configPrefixed: false, alias: 'proxy.proxy', // also configures Factoryable alternateClassName: [ 'Ext.data.DataProxy', 'Ext.data.Proxy' ], requires: [ 'Ext.data.schema.Schema', 'Ext.data.reader.Reader', 'Ext.data.writer.Writer' ], uses: [ 'Ext.data.Batch', 'Ext.data.operation.*', 'Ext.data.Model' ], config: { /** * @cfg {String} batchOrder * Comma-separated ordering 'create', 'update' and 'destroy' actions when batching. Override this to set a different * order for the batched CRUD actions to be executed in. Defaults to 'create,update,destroy'. */ batchOrder: 'create,update,destroy', /** * @cfg {Boolean} batchActions * True to batch actions of a particular type when synchronizing the store. Defaults to true. */ batchActions: true, /** * @cfg {String/Ext.data.Model} model * The name of the Model to tie to this Proxy. Can be either the string name of the Model, or a reference to the * Model constructor. Required. */ model: undefined, // @cmd-auto-dependency {aliasPrefix : "reader.", defaultPropertyName : "defaultReaderType"} /** * @cfg {Object/String/Ext.data.reader.Reader} reader * The Ext.data.reader.Reader to use to decode the server's response or data read * from client. This can either be a Reader instance, a config object or just a * valid Reader type name (e.g. 'json', 'xml'). */ reader: { type: 'json' }, // @cmd-auto-dependency {aliasPrefix : "writer.", defaultPropertyName : "defaultWriterType"} /** * @cfg {Object/String/Ext.data.writer.Writer} writer * The Ext.data.writer.Writer to use to encode any request sent to the server or * saved to client. This can either be a Writer instance, a config object or just * a valid Writer type name (e.g. 'json', 'xml'). */ writer: { type: 'json' } }, /** * @property {Boolean} isProxy * `true` in this class to identify an object as an instantiated Proxy, or subclass thereof. */ isProxy: true, /** * @property {Boolean} [isSynchronous=false] * Identifies the proxy as (a)synchronous. */ isSynchronous: false, /** * @event metachange * Fires when this proxy's reader provides new metadata. Metadata usually consists * of new field definitions, but can include any configuration data required by an * application, and can be processed as needed in the event handler. * This event is currently only fired for JsonReaders. Note that this event is also * propagated by {@link Ext.data.Store}, which is typically where it would be handled. * @param {Ext.data.proxy.Proxy} this * @param {Object} meta The JSON metadata */ /** * Creates the Proxy * @param {Object} [config] Config object. */ constructor: function(config) { // Will call initConfig this.mixins.observable.constructor.call(this, config); }, applyModel: function(model) { return Ext.data.schema.Schema.lookupEntity(model); }, updateModel: function(model) { if (model) { var reader = this.getReader(); if (reader && !reader.getModel()) { reader.setModel(model); } } }, applyReader: function(reader) { return Ext.Factory.reader(reader); }, updateReader: function (reader) { if (reader) { var me = this, model = me.getModel(); if (!model) { model = reader.getModel(); if (model) { me.setModel(model); } } else { reader.setModel(model); } // TODO: an event here? if (reader.onMetaChange) { reader.onMetaChange = Ext.Function.createSequence(reader.onMetaChange, me.onMetaChange, me); } } }, applyWriter: function(writer) { return Ext.Factory.writer(writer); }, abort: Ext.emptyFn, /** * @private * Called each time the reader's onMetaChange is called so that the proxy can fire the metachange event */ onMetaChange: function(meta) { this.fireEvent('metachange', this, meta); }, /** * Performs the given create operation. * @param {Ext.data.operation.Operation} operation The Operation to perform * @method */ create: Ext.emptyFn, /** * Performs the given read operation. * @param {Ext.data.operation.Operation} operation The Operation to perform * @method */ read: Ext.emptyFn, /** * Performs the given update operation. * @param {Ext.data.operation.Operation} operation The Operation to perform * @method */ update: Ext.emptyFn, /** * Performs the given destroy operation. * @param {Ext.data.operation.Operation} operation The Operation to perform * @method */ erase: Ext.emptyFn, /** * Performs a batch of {@link Ext.data.operation.Operation Operations}, in the order specified by {@link #batchOrder}. Used * internally by {@link Ext.data.Store}'s {@link Ext.data.Store#sync sync} method. Example usage: * * myProxy.batch({ * create : [myModel1, myModel2], * update : [myModel3], * destroy: [myModel4, myModel5] * }); * * Where the myModel* above are {@link Ext.data.Model Model} instances - in this case 1 and 2 are new instances and * have not been saved before, 3 has been saved previously but needs to be updated, and 4 and 5 have already been * saved but should now be destroyed. * * Note that the previous version of this method took 2 arguments (operations and listeners). While this is still * supported for now, the current signature is now a single `options` argument that can contain both operations and * listeners, in addition to other options. The multi-argument signature will likely be deprecated in a future release. * * @param {Object} options Object containing one or more properties supported by the batch method: * * @param {Object} options.operations Object containing the Model instances to act upon, keyed by action name * * @param {Object} [options.listeners] Event listeners object passed straight through to the Batch - * see {@link Ext.data.Batch} for details * * @param {Ext.data.Batch/Object} [options.batch] A {@link Ext.data.Batch} object (or batch config to apply * to the created batch). If unspecified a default batch will be auto-created. * * @param {Function} [options.callback] The function to be called upon completion of processing the batch. * The callback is called regardless of success or failure and is passed the following parameters: * @param {Ext.data.Batch} options.callback.batch The {@link Ext.data.Batch batch} that was processed, * containing all operations in their current state after processing * @param {Object} options.callback.options The options argument that was originally passed into batch * * @param {Function} [options.success] The function to be called upon successful completion of the batch. The * success function is called only if no exceptions were reported in any operations. If one or more exceptions * occurred then the `failure` function will be called instead. The success function is called * with the following parameters: * @param {Ext.data.Batch} options.success.batch The {@link Ext.data.Batch batch} that was processed, * containing all operations in their current state after processing * @param {Object} options.success.options The options argument that was originally passed into batch * * @param {Function} [options.failure] The function to be called upon unsuccessful completion of the batch. The * failure function is called when one or more operations returns an exception during processing (even if some * operations were also successful). In this case you can check the batch's {@link Ext.data.Batch#exceptions * exceptions} array to see exactly which operations had exceptions. The failure function is called with the * following parameters: * @param {Ext.data.Batch} options.failure.batch The {@link Ext.data.Batch batch} that was processed, * containing all operations in their current state after processing * @param {Object} options.failure.options The options argument that was originally passed into batch * * @param {Object} [options.scope] The scope in which to execute any callbacks (i.e. the `this` object inside * the callback, success and/or failure functions). Defaults to the proxy. * * @return {Ext.data.Batch} The newly created Batch */ batch: function(options, /* deprecated */listeners) { var me = this, useBatch = me.getBatchActions(), batch, records, actions, aLen, action, a, r, rLen, record; if (options.operations === undefined) { // the old-style (operations, listeners) signature was called // so convert to the single options argument syntax options = { operations: options, listeners: listeners }; } if (options.batch) { if (Ext.isDefined(options.batch.runOperation)) { batch = Ext.applyIf(options.batch, { proxy: me, listeners: {} }); } } else { options.batch = { proxy: me, listeners: options.listeners || {} }; } if (!batch) { batch = new Ext.data.Batch(options.batch); } batch.on('complete', Ext.bind(me.onBatchComplete, me, [options], 0)); actions = me.getBatchOrder().split(','); aLen = actions.length; for (a = 0; a < aLen; a++) { action = actions[a]; records = options.operations[action]; if (records) { if (useBatch) { batch.add(me.createOperation(action, { records : records, // Relay any additional params through to the Operation (and Request). params: options.params })); } else { rLen = records.length; for (r = 0; r < rLen; r++) { record = records[r]; batch.add(me.createOperation(action, { records : [record], // Relay any additional params through to the Operation (and Request). params: options.params })); } } } } batch.start(); return batch; }, /** * @private * The internal callback that the proxy uses to call any specified user callbacks after completion of a batch */ onBatchComplete: function(batchOptions, batch) { var scope = batchOptions.scope || this; if (batch.hasException()) { if (Ext.isFunction(batchOptions.failure)) { Ext.callback(batchOptions.failure, scope, [batch, batchOptions]); } } else if (Ext.isFunction(batchOptions.success)) { Ext.callback(batchOptions.success, scope, [batch, batchOptions]); } if (Ext.isFunction(batchOptions.callback)) { Ext.callback(batchOptions.callback, scope, [batch, batchOptions]); } }, createOperation: function(action, config) { var operation = Ext.createByAlias('data.operation.' + action, config); operation.setProxy(this); return operation; }, clone: function() { return new this.self(this.getInitialConfig()); }});