Issue #1812866 by mkadin, effulgentsia: rebuild the server side AJAX API.

core/lib/Drupal/Core/Ajax/AddCssCommand.php

+<?php
+
+/**
+ * @file
+ * Definition of Drupal\Core\Ajax\AddCssCommand.
+ */
+
+namespace Drupal\Core\Ajax;
+
+use Drupal\Core\Ajax\CommandInterface;
+
+/**
+ * An AJAX command for adding css to the page via ajax.
+ *
+ * This command is implemented by Drupal.ajax.prototype.commands.add_css()
+ * defined in misc/ajax.js.
+ *
+ * @see misc/ajax.js
+ */
+class AddCssCommand implements CommandInterface {
+
+  /**
+   * A string that contains the styles to be added to the page.
+   *
+   * It should include the wrapping style tag.
+   *
+   * @var string
+   */
+  protected $styles;
+
+  /**
+   * Constructs an AddCssCommand.
+   *
+   * @param string $styles
+   *   A string that contains the styles to be added to the page, including the
+   *   wrapping <style> tag.
+   */
+  public function __construct($styles) {
+    $this->styles = $styles;
+  }
+
+  /**
+   * Implements Drupal\Core\Ajax\CommandInterface:render().
+   */
+  public function render() {
+
+    return array(
+      'command' => 'add_css',
+      'data' => $this->styles,
+    );
+  }
+
+}

core/lib/Drupal/Core/Ajax/AfterCommand.php

+<?php
+
+/**
+ * @file
+ * Definition of Drupal\Core\Ajax\AfterCommand.
+ */
+
+namespace Drupal\Core\Ajax;
+
+use Drupal\Core\Ajax\InsertCommand;
+
+/**
+ * An AJAX command for calling the jQuery after() method.
+ *
+ * The 'insert/after' command instructs the client to use jQuery's after()
+ * method to insert the given HTML content after each element matched by the
+ * given selector.
+ *
+ * This command is implemented by Drupal.ajax.prototype.commands.insert()
+ * defined in misc/ajax.js.
+ *
+ * @see http://docs.jquery.com/Manipulation/after#content
+ */
+class AfterCommand extends InsertCommand {
+
+  /**
+   * Implements Drupal\Core\Ajax\CommandInterface:render().
+   */
+  public function render() {
+
+    return array(
+      'command' => 'insert',
+      'method' => 'after',
+      'selector' => $this->selector,
+      'data' => $this->html,
+      'settings' => $this->settings,
+    );
+  }
+
+}

core/lib/Drupal/Core/Ajax/AjaxResponse.php

+<?php
+
+/**
+ * @file
+ * Definition of Drupal\Core\Ajax\AjaxResponse.
+ */
+
+namespace Drupal\Core\Ajax;
+
+use Symfony\Component\HttpFoundation\JsonResponse;
+use Symfony\Component\HttpFoundation\Request;
+
+/**
+ * JSON response object for AJAX requests.
+ */
+class AjaxResponse extends JsonResponse {
+
+  /**
+   * The array of ajax commands.
+   *
+   * @var array
+   */
+  protected $commands = array();
+
+  /**
+   * Add an AJAX command to the response.
+   *
+   * @param object $command
+   *   An AJAX command object implementing CommandInterface.
+   *
+   * @return AjaxResponse
+   *   The current AjaxResponse.
+   */
+  public function addCommand($command) {
+    $this->commands[] = $command->render();
+    return $this;
+  }
+
+  /**
+   * Sets the response's data to be the array of AJAX commands.
+   *
+   * @param
+   *   $request A request object.
+   *
+   * @return
+   *   Response The current response.
+   */
+  public function prepare(Request $request) {
+
+    parent::setData($this->ajaxRender($request));
+    return parent::prepare($request);
+  }
+
+  /**
+   * Prepares the AJAX commands for sending back to the client.
+   *
+   * @param Request
+   *   The request object that the AJAX is responding to.
+   *
+   * @return array
+   *   An array of commands ready to be returned as JSON.
+   */
+  protected function ajaxRender($request) {
+    // Ajax responses aren't rendered with html.tpl.php, so we have to call
+    // drupal_get_css() and drupal_get_js() here, in order to have new files
+    // added during this request to be loaded by the page. We only want to send
+    // back files that the page hasn't already loaded, so we implement simple
+    // diffing logic using array_diff_key().
+    foreach (array('css', 'js') as $type) {
+      // It is highly suspicious if $_POST['ajax_page_state'][$type] is empty,
+      // since the base page ought to have at least one JS file and one CSS file
+      // loaded. It probably indicates an error, and rather than making the page
+      // reload all of the files, instead we return no new files.
+      if (empty($request->parameters['ajax_page_state'][$type])) {
+        $items[$type] = array();
+      }
+      else {
+        $function = 'drupal_add_' . $type;
+        $items[$type] = $function();
+        drupal_alter($type, $items[$type]);
+        // @todo Inline CSS and JS items are indexed numerically. These can't be
+        //   reliably diffed with array_diff_key(), since the number can change
+        //   due to factors unrelated to the inline content, so for now, we
+        //   strip the inline items from Ajax responses, and can add support for
+        //   them when drupal_add_css() and drupal_add_js() are changed to using
+        //   md5() or some other hash of the inline content.
+        foreach ($items[$type] as $key => $item) {
+          if (is_numeric($key)) {
+            unset($items[$type][$key]);
+          }
+        }
+        // Ensure that the page doesn't reload what it already has.
+        $items[$type] = array_diff_key($items[$type], $request->parameters['ajax_page_state'][$type]);
+      }
+    }
+
+    // Render the HTML to load these files, and add AJAX commands to insert this
+    // HTML in the page. We pass TRUE as the $skip_alter argument to prevent the
+    // data from being altered again, as we already altered it above. Settings
+    // are handled separately, afterwards.
+    if (isset($items['js']['settings'])) {
+      unset($items['js']['settings']);
+    }
+    $styles = drupal_get_css($items['css'], TRUE);
+    $scripts_footer = drupal_get_js('footer', $items['js'], TRUE);
+    $scripts_header = drupal_get_js('header', $items['js'], TRUE);
+
+    if (!empty($styles)) {
+      $this->addCommand(new AddCssCommand($styles));
+    }
+    if (!empty($scripts_header)) {
+      $this->addCommand(new PrependCommand('head', $scripts_header));
+    }
+    if (!empty($scripts_footer)) {
+      $this->addCommand(new AppendCommand('body', $scripts_footer));
+    }
+
+    // Now add a command to merge changes and additions to Drupal.settings.
+    $scripts = drupal_add_js();
+    if (!empty($scripts['settings'])) {
+      $settings = $scripts['settings'];
+      $this->addCommand(new SettingsCommand(call_user_func_array('array_merge_recursive', $settings['data']), TRUE));
+    }
+
+    $commands = $this->commands;
+    drupal_alter('ajax_render', $commands);
+
+    return $commands;
+  }
+
+}

core/lib/Drupal/Core/Ajax/AlertCommand.php

+<?php
+
+/**
+ * @file
+ * Definition of Drupal\Core\Ajax\AlertCommand.
+ */
+
+namespace Drupal\Core\Ajax;
+
+use Drupal\Core\Ajax\CommandInterface;
+
+/**
+ * AJAX command for a javascript alert box.
+ */
+class AlertCommand implements CommandInterface {
+
+  /**
+   * The text to be displayed in the alert box.
+   *
+   * @var string
+   */
+  protected $text;
+
+  /**
+   * Constructs an AlertCommand object.
+   *
+   * @param string $text
+   *   The text to be displayed in the alert box.
+   */
+  public function __construct($text) {
+    $this->text = $text;
+  }
+
+  /**
+   * Implements Drupal\Core\Ajax\CommandInterface:render().
+   */
+  public function render() {
+
+    return array(
+      'command' => 'alert',
+      'text' => $this->text,
+    );
+  }
+
+}

core/lib/Drupal/Core/Ajax/AppendCommand.php

+<?php
+
+/**
+ * @file
+ * Definition of Drupal\Core\Ajax\AppendCommand.
+ */
+
+namespace Drupal\Core\Ajax;
+
+use Drupal\Core\Ajax\InsertCommand;
+
+/**
+ * An AJAX command for calling the jQuery append() method.
+ *
+ * The 'insert/append' command instructs the client to use jQuery's append()
+ * method to append the given HTML content to the inside of each element matched
+ * by the given selector.
+ *
+ * This command is implemented by Drupal.ajax.prototype.commands.insert()
+ * defined in misc/ajax.js.
+ *
+ * @see http://docs.jquery.com/Manipulation/append#content
+ */
+class AppendCommand extends InsertCommand {
+
+  /**
+   * Implements Drupal\Core\Ajax\CommandInterface:render().
+   */
+  public function render() {
+
+    return array(
+      'command' => 'insert',
+      'method' => 'append',
+      'selector' => $this->selector,
+      'data' => $this->html,
+      'settings' => $this->settings,
+    );
+  }
+
+}

core/lib/Drupal/Core/Ajax/BeforeCommand.php

+<?php
+
+/**
+ * @file
+ * Definition of Drupal\Core\Ajax\InsertCommand.
+ */
+
+namespace Drupal\Core\Ajax;
+
+use Drupal\Core\Ajax\InsertCommand;
+
+/**
+ * An AJAX command for calling the jQuery before() method.
+ *
+ * The 'insert/before' command instructs the client to use jQuery's before()
+ * method to insert the given HTML content before each of elements matched by
+ * the given selector.
+ *
+ * This command is implemented by Drupal.ajax.prototype.commands.insert()
+ * defined in misc/ajax.js.
+ *
+ * @see http://docs.jquery.com/Manipulation/before#content
+ */
+class BeforeCommand extends InsertCommand {
+
+  /**
+   * Implements Drupal\Core\Ajax\CommandInterface:render().
+   */
+  public function render() {
+
+    return array(
+      'command' => 'insert',
+      'method' => 'before',
+      'selector' => $this->selector,
+      'data' => $this->html,
+      'settings' => $this->settings,
+    );
+  }
+
+}

core/lib/Drupal/Core/Ajax/ChangedCommand.php

+<?php
+
+/**
+ * @file
+ * Definition of Drupal\Core\Ajax\ChangedCommand.
+ */
+
+namespace Drupal\Core\Ajax;
+
+use Drupal\Core\Ajax\CommandInterface;
+
+/**
+ * An AJAX command for marking HTML elements as changed.
+ *
+ * This command instructs the client to mark each of the elements matched by the
+ * given selector as 'ajax-changed'.
+ *
+ * This command is implemented by Drupal.ajax.prototype.commands.changed()
+ * defined in misc/ajax.js.
+ */
+class ChangedCommand implements CommandInterface {
+
+  /**
+   * A CSS selector string.
+   *
+   * If the command is a response to a request from an #ajax form element then
+   * this value can be NULL.
+   *
+   * @var string
+   */
+  protected $selector;
+
+  /**
+   * An optional CSS selector for elements to which asterisks will be appended.
+   *
+   * @var string
+   */
+  protected $asterisk;
+
+  /**
+   * Constructs a ChangedCommand object.
+   *
+   * @param string $selector
+   *   CSS selector for elements to be marked as changed.
+   * @param string $asterisk
+   *   CSS selector for elements to which an asterisk will be appended.
+   */
+  public function __construct($selector, $asterisk = '') {
+    $this->selector = $selector;
+    $this->asterisk = $asterisk;
+  }
+
+  /**
+   * Implements Drupal\Core\Ajax\CommandInterface:render().
+   */
+  public function render() {
+
+    return array(
+      'command' => 'changed',
+      'selector' => $this->selector,
+      'asterisk' => $this->asterisk,
+    );
+  }
+
+}

core/lib/Drupal/Core/Ajax/CommandInterface.php

+<?php
+
+/**
+ * @file
+ * Definition of Drupal\Core\Ajax\CommandInterface.
+ */
+
+namespace Drupal\Core\Ajax;
+
+/**
+ * AJAX command interface.
+ *
+ * All AJAX commands passed to AjaxResponse objects should implement these
+ * methods.
+ */
+interface CommandInterface {
+
+  /**
+   * Return an array to be run through json_encode and sent to the client.
+   */
+  public function render();
+}

core/lib/Drupal/Core/Ajax/CssCommand.php

+<?php
+
+/**
+ * @file
+ * Definition of Drupal\Core\Ajax\CssCommand.
+ */
+
+namespace Drupal\Core\Ajax;
+
+use Drupal\Core\Ajax\CommandInterface;
+
+/**
+ * An AJAX command for calling the jQuery css() method.
+ *
+ * The 'css' command will instruct the client to use the jQuery css() method to
+ * apply the CSS arguments to elements matched by the given selector.
+ *
+ * This command is implemented by Drupal.ajax.prototype.commands.css() defined
+ * in misc/ajax.js.
+ *
+ * @see http://docs.jquery.com/CSS/css#properties
+ */
+class CssCommand implements CommandInterface {
+
+  /**
+   * A CSS selector string.
+   *
+   * If the command is a response to a request from an #ajax form element then
+   * this value can be NULL.
+   *
+   * @var string
+   */
+  protected $selector;
+
+  /**
+   * An array of property/value pairs to set in the CSS for the selector.
+   *
+   * @var array
+   */
+  protected $css = array();
+
+  /**
+   * Constructs a CssCommand object.
+   *
+   * @param string $selector
+   *   A CSS selector for elements to which the CSS will be applied.
+   * @param array $css
+   *   An array of CSS property/value pairs to set.
+   */
+  public function __construct($selector, array $css = array()) {
+    $this->selector = $selector;
+    $this->css = $css;
+  }
+
+  /**
+   * Adds a property/value pair to the CSS to be added to this element.
+   *
+   * @param $property
+   *   The CSS property to be changed.
+   * @param $value
+   *   The new value of the CSS property.
+   */
+  public function setProperty($property, $value) {
+    $this->css[$property] = $value;
+    return $this;
+  }
+
+  /**
+   * Implements Drupal\Core\Ajax\CommandInterface:render().
+   */
+  public function render() {
+
+    return array(
+      'command' => 'css',
+      'selector' => $this->selector,
+      'argument' => $this->css,
+    );
+  }
+
+}

core/lib/Drupal/Core/Ajax/DataCommand.php

+<?php
+
+/**
+ * @file
+ * Definition of Drupal\Core\Ajax\DataCommand.
+ */
+
+namespace Drupal\Core\Ajax;
+
+use Drupal\Core\Ajax\CommandInterface;
+
+/**
+ * An AJAX command for implementing jQuery's data() method.
+ *
+ * This instructs the client to attach the name=value pair of data to the
+ * selector via jQuery's data cache.
+ *
+ * This command is implemented by Drupal.ajax.prototype.commands.data() defined
+ * in misc/ajax.js.
+ */
+class DataCommand implements CommandInterface {
+
+  /**
+   * A CSS selector string for elements to which data will be attached.
+   *
+   * If the command is a response to a request from an #ajax form element then
+   * this value can be NULL.
+   *
+   * @var string
+   */
+  protected $selector;
+
+  /**
+   * The key of the data attached to elements matched by the selector.
+   *
+   * @var string
+   */
+  protected $name;
+
+  /**
+   * The value of the data to be atached to elements matched by the selector.
+   *
+   * The data is not limited to strings; it can be any format.
+   *
+   * @var mixed
+   */
+  protected $value;
+
+  /**
+   * Constructs a DataCommand object.
+   *
+   * @param string $selector
+   *   A CSS selector for the elements to which the data will be attached.
+   * @param string $name
+   *   The key of the data to be attached to elements matched by the selector.
+   * @param type $value
+   *   The value of the data to be attached to elements matched by the selector.
+   */
+  public function __construct($selector, $name, $value) {
+    $this->selector = $selector;
+    $this->name = $name;
+    $this->value = $value;
+  }
+
+  /**
+   * Implements Drupal\Core\Ajax\CommandInterface:render().
+   */
+  public function render() {
+
+    return array(
+      'command' => 'data',
+      'selector' => $this->selector,
+      'name' => $this->name,
+      'value' => $this->value,
+    );
+  }
+
+}
+

core/lib/Drupal/Core/Ajax/HtmlCommand.php

+<?php
+
+/**
+ * @file
+ * Definition of Drupal\Core\Ajax\HtmlCommand.
+ */
+
+namespace Drupal\Core\Ajax;
+
+use Drupal\Core\Ajax\InsertCommand;
+
+/**
+ * AJAX command for calling the jQuery html() method.
+ *
+ * The 'insert/html' command instructs the client to use jQuery's html() method