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17 * @class Ext.data.proxy.Ajax
18 * @extends Ext.data.proxy.Server
20 * <p>AjaxProxy is one of the most widely-used ways of getting data into your application. It uses AJAX requests to
21 * load data from the server, usually to be placed into a {@link Ext.data.Store Store}. Let's take a look at a typical
22 * setup. Here we're going to set up a Store that has an AjaxProxy. To prepare, we'll also set up a
23 * {@link Ext.data.Model Model}:</p>
27 extend: 'Ext.data.Model',
28 fields: ['id', 'name', 'email']
31 //The Store contains the AjaxProxy as an inline configuration
32 var store = new Ext.data.Store({
43 * <p>Our example is going to load user data into a Store, so we start off by defining a {@link Ext.data.Model Model}
44 * with the fields that we expect the server to return. Next we set up the Store itself, along with a {@link #proxy}
45 * configuration. This configuration was automatically turned into an Ext.data.proxy.Ajax instance, with the url we
46 * specified being passed into AjaxProxy's constructor. It's as if we'd done this:</p>
49 new Ext.data.proxy.Ajax({
56 * <p>A couple of extra configurations appeared here - {@link #model} and {@link #reader}. These are set by default
57 * when we create the proxy via the Store - the Store already knows about the Model, and Proxy's default
58 * {@link Ext.data.reader.Reader Reader} is {@link Ext.data.reader.Json JsonReader}.</p>
60 * <p>Now when we call store.load(), the AjaxProxy springs into action, making a request to the url we configured
61 * ('users.json' in this case). As we're performing a read, it sends a GET request to that url (see {@link #actionMethods}
62 * to customize this - by default any kind of read will be sent as a GET request and any kind of write will be sent as a
65 * <p><u>Limitations</u></p>
67 * <p>AjaxProxy cannot be used to retrieve data from other domains. If your application is running on http://domainA.com
68 * it cannot load data from http://domainB.com because browsers have a built-in security policy that prohibits domains
69 * talking to each other via AJAX.</p>
71 * <p>If you need to read data from another domain and can't set up a proxy server (some software that runs on your own
72 * domain's web server and transparently forwards requests to http://domainB.com, making it look like they actually came
73 * from http://domainA.com), you can use {@link Ext.data.proxy.JsonP} and a technique known as JSON-P (JSON with
74 * Padding), which can help you get around the problem so long as the server on http://domainB.com is set up to support
75 * JSON-P responses. See {@link Ext.data.proxy.JsonP JsonPProxy}'s introduction docs for more details.</p>
77 * <p><u>Readers and Writers</u></p>
79 * <p>AjaxProxy can be configured to use any type of {@link Ext.data.reader.Reader Reader} to decode the server's response. If
80 * no Reader is supplied, AjaxProxy will default to using a {@link Ext.data.reader.Json JsonReader}. Reader configuration
81 * can be passed in as a simple object, which the Proxy automatically turns into a {@link Ext.data.reader.Reader Reader}
85 var proxy = new Ext.data.proxy.Ajax({
93 proxy.getReader(); //returns an {@link Ext.data.reader.Xml XmlReader} instance based on the config we supplied
96 * <p><u>Url generation</u></p>
98 * <p>AjaxProxy automatically inserts any sorting, filtering, paging and grouping options into the url it generates for
99 * each request. These are controlled with the following configuration options:</p>
101 * <ul style="list-style-type: disc; padding-left: 20px;">
102 * <li>{@link #pageParam} - controls how the page number is sent to the server
103 * (see also {@link #startParam} and {@link #limitParam})</li>
104 * <li>{@link #sortParam} - controls how sort information is sent to the server</li>
105 * <li>{@link #groupParam} - controls how grouping information is sent to the server</li>
106 * <li>{@link #filterParam} - controls how filter information is sent to the server</li>
109 * <p>Each request sent by AjaxProxy is described by an {@link Ext.data.Operation Operation}. To see how we can
110 * customize the generated urls, let's say we're loading the Proxy with the following Operation:</p>
113 var operation = new Ext.data.Operation({
119 * <p>Now we'll issue the request for this Operation by calling {@link #read}:</p>
122 var proxy = new Ext.data.proxy.Ajax({
126 proxy.read(operation); //GET /users?page=2
129 * <p>Easy enough - the Proxy just copied the page property from the Operation. We can customize how this page data is
130 * sent to the server:</p>
133 var proxy = new Ext.data.proxy.Ajax({
135 pagePage: 'pageNumber'
138 proxy.read(operation); //GET /users?pageNumber=2
141 * <p>Alternatively, our Operation could have been configured to send start and limit parameters instead of page:</p>
144 var operation = new Ext.data.Operation({
150 var proxy = new Ext.data.proxy.Ajax({
154 proxy.read(operation); //GET /users?start=50&limit=25
157 * <p>Again we can customize this url:</p>
160 var proxy = new Ext.data.proxy.Ajax({
162 startParam: 'startIndex',
163 limitParam: 'limitIndex'
166 proxy.read(operation); //GET /users?startIndex=50&limitIndex=25
169 * <p>AjaxProxy will also send sort and filter information to the server. Let's take a look at how this looks with a
170 * more expressive Operation object:</p>
173 var operation = new Ext.data.Operation({
176 new Ext.util.Sorter({
180 new Ext.util.Sorter({
186 new Ext.util.Filter({
187 property: 'eyeColor',
194 * <p>This is the type of object that is generated internally when loading a {@link Ext.data.Store Store} with sorters
195 * and filters defined. By default the AjaxProxy will JSON encode the sorters and filters, resulting in something like
196 * this (note that the url is escaped before sending the request, but is left unescaped here for clarity):</p>
199 var proxy = new Ext.data.proxy.Ajax({
203 proxy.read(operation); //GET /users?sort=[{"property":"name","direction":"ASC"},{"property":"age","direction":"DESC"}]&filter=[{"property":"eyeColor","value":"brown"}]
206 * <p>We can again customize how this is created by supplying a few configuration options. Let's say our server is set
207 * up to receive sorting information is a format like "sortBy=name#ASC,age#DESC". We can configure AjaxProxy to provide
208 * that format like this:</p>
211 var proxy = new Ext.data.proxy.Ajax({
214 filterParam: 'filterBy',
216 //our custom implementation of sorter encoding - turns our sorters into "name#ASC,age#DESC"
217 encodeSorters: function(sorters) {
218 var length = sorters.length,
222 for (i = 0; i < length; i++) {
225 sortStrs[i] = sorter.property + '#' + sorter.direction
228 return sortStrs.join(",");
232 proxy.read(operation); //GET /users?sortBy=name#ASC,age#DESC&filterBy=[{"property":"eyeColor","value":"brown"}]
235 * <p>We can also provide a custom {@link #encodeFilters} function to encode our filters.</p>
239 * <p>Note that if this HttpProxy is being used by a {@link Ext.data.Store Store}, then the
240 * Store's call to {@link #load} will override any specified <tt>callback</tt> and <tt>params</tt>
241 * options. In this case, use the Store's {@link Ext.data.Store#events events} to modify parameters,
242 * or react to loading events. The Store's {@link Ext.data.Store#baseParams baseParams} may also be
243 * used to pass parameters known at instantiation time.</p>
245 * <p>If an options parameter is passed, the singleton {@link Ext.Ajax} object will be used to make
248 Ext.define('Ext.data.proxy.Ajax', {
249 requires: ['Ext.util.MixedCollection', 'Ext.Ajax'],
250 extend: 'Ext.data.proxy.Server',
252 alternateClassName: ['Ext.data.HttpProxy', 'Ext.data.AjaxProxy'],
255 * @property actionMethods
256 * Mapping of action name to HTTP request method. In the basic AjaxProxy these are set to 'GET' for 'read' actions and 'POST'
257 * for 'create', 'update' and 'destroy' actions. The {@link Ext.data.proxy.Rest} maps these to the correct RESTful methods.
267 * @cfg {Object} headers Any headers to add to the Ajax request. Defaults to <tt>undefined</tt>.
273 doRequest: function(operation, callback, scope) {
274 var writer = this.getWriter(),
275 request = this.buildRequest(operation, callback, scope);
277 if (operation.allowWrite()) {
278 request = writer.write(request);
282 headers : this.headers,
283 timeout : this.timeout,
285 callback : this.createRequestCallback(request, operation, callback, scope),
286 method : this.getMethod(request),
287 disableCaching: false // explicitly set it to false, ServerProxy handles caching
290 Ext.Ajax.request(request);
296 * Returns the HTTP method name for a given request. By default this returns based on a lookup on {@link #actionMethods}.
297 * @param {Ext.data.Request} request The request object
298 * @return {String} The HTTP method to use (should be one of 'GET', 'POST', 'PUT' or 'DELETE')
300 getMethod: function(request) {
301 return this.actionMethods[request.action];
306 * TODO: This is currently identical to the JsonPProxy version except for the return function's signature. There is a lot
307 * of code duplication inside the returned function so we need to find a way to DRY this up.
308 * @param {Ext.data.Request} request The Request object
309 * @param {Ext.data.Operation} operation The Operation being executed
310 * @param {Function} callback The callback function to be called when the request completes. This is usually the callback
311 * passed to doRequest
312 * @param {Object} scope The scope in which to execute the callback function
313 * @return {Function} The callback function
315 createRequestCallback: function(request, operation, callback, scope) {
318 return function(options, success, response) {
319 me.processResponse(success, operation, request, response, callback, scope);
323 //backwards compatibility, remove in Ext JS 5.0
324 Ext.data.HttpProxy = this;