From a2189aadc2408efb61debac788f1c4ef48d0a081 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?J=2E=20Rene=CC=81e=20Beach?= <splendidnoise@gmail.com>
Date: Wed, 16 Apr 2014 16:52:41 -0400
Subject: [PATCH] docs
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Signed-off-by: J. Renée Beach <splendidnoise@gmail.com>
---
 core/modules/system/core.api.php | 59 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 59 insertions(+)

diff --git a/core/modules/system/core.api.php b/core/modules/system/core.api.php
index 1ecc9c1..d16a958 100644
--- a/core/modules/system/core.api.php
+++ b/core/modules/system/core.api.php
@@ -120,6 +120,65 @@
  * overview level. And link to more detailed documentation.
  *
  * See https://drupal.org/developing/api/entity
+ *
+ * @section config_dependencies Configuration Dependencies
+ *
+ * Dependencies are declared in a plugin's definition. A system menu block is an
+ * example from Drupal core that utilizes this pattern. The menu block declares a
+ * dependency on the menu's corresponding entity. The following code illustrates
+ * how this association is established through the following method:
+ *
+ * @code
+ * // Drupal\Core\Config\Entity\ConfigEntityBase::calculateDependencies
+ * public function calculateDependencies() {
+ *   // Dependencies should be recalculated on every save. This ensures stale
+ *   // dependencies are never saved.
+ *   $this->dependencies = array();
+ *   if ($this instanceof EntityWithPluginBagInterface) {
+ *     // Configuration entities need to depend on the providers of any plugins
+ *     // that they store the configuration for.
+ *     $plugin_bag = $this->getPluginBag();
+ *     foreach($plugin_bag as $instance) {
+ *       $definition = $instance->getPluginDefinition();
+ *       $this->addDependency('module', $definition['provider']);
+ *       // Plugins can declare additional dependencies in their definition.
+ *       if (isset($definition['config_dependencies'])) {
+ *         foreach ($definition['config_dependencies'] as $type => $dependencies) {
+ *           foreach ($dependencies as $dependency) {
+ *             $this->addDependency($type, $dependency);
+ *           }
+ *         }
+ *       }
+ *     }
+ *   }
+ *   return $this->dependencies;
+ * }
+ * @endcode
+ *
+ * The config_dependencies key in the plugins' definition is assigned an array of
+ * dependencies. The keys of this array may be one of:
+ *   - entity
+ *   - module
+ *   - theme
+ *
+ * For example, the system menu block for the Bartik theme declares the following
+ * dependencies in its configuration definition file.
+ *
+ * @code
+ * // core/profiles/standard/config/block.block.bartik_footer.yml
+ * id: bartik_footer
+ * theme: bartik
+ * ...
+ * dependencies:
+ *   entity:
+ *     - system.menu.footer
+ *   module:
+ *     - system
+ *   theme:
+ *     - bartik
+ * @endcode
+ *
+ * @see https://drupal.org/documentation/administer/config
  * @}
  */
 
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1.8.5.3