Scheduled jobs

Author: simpleadm

1. Magento Architecture and Customization Techniques/5. Demonstrate ability to use plugins.md

@@ -39,6 +39,24 @@ The `sortOrder` property controls how your plugin interacts with other plugins o
 >
 > -- [Magento DevDocs - Plugins](https://devdocs.magento.com/guides/v2.2/extension-dev-guide/plugins.html#prioritizing-plugins)
 
+Plugin sortOrder:
+
+- before sortOrder=10, before sortOrder=20, before sortOrder=30 ...
+- before and around (first half) called together for same plugin!
+- around (second half) and after called together for same plugin!
+
+Example:
+
+- pluginA.beforeMethod, pluginA.aroundMethod first half
+- pluginB.beforeMethod, pluginB.aroundMethod first half
+- pluginC.beforeMethod, `____________________
+- ____________________, pluginD.aroundMethod first half
+- method()
+- ____________________, pluginD.aroundMethod second half
+- pluginC.afterMethod , ________________________________
+- pluginB.aroundMethod second half, pluginB.afterMethod
+- pluginA.aroundMethod second half, pluginA.afterMethod
+
 ### Identify strengths and weaknesses of plugins.
 
 > The greatest weakness is exploited in the hands of a developer who is either not

1. Magento Architecture and Customization Techniques/6. Configure event observers and scheduled jobs.md

@@ -1,29 +1,86 @@
 # Configure event observers and scheduled jobs
 
+## Observers
+
+Events are dispatched by modules when certain actions are triggered.
+In addition to its own events, Magento allows you to create your own events that can be dispatched in your code.
+When an event is dispatched, it can pass data to any observers configured to watch that event.
+
+Best practices:
+- Make your observer efficient
+- Do not include business logic
+- Declare observer in the appropriate scope
+- Avoid cyclical event loops
+- Do not rely on invocation order
+
+> 
+> `14. Events`
+> 
+> 14.1. All values (including objects) passed to an event MUST NOT be modified in the event observer. Instead, plugins SHOULD BE used for modifying the input or output of a function.
+>
+> -- [Magento DevDocs - Technical guidelines](https://devdocs.magento.com/guides/v2.2/coding-standards/technical-guidelines.html)
+
+
 ### Demonstrate how to configure observers
 - can define observer in global area, then disable in specific area
 
-Observer sortOrder:
+Observers can be configured in the `events.xml` file.
+
+Properties:
+- name (required) - Name of the observer for the event definition
+- instance (required) - Class name of the observer
+- disabled - Is observer active or not (Default: false)
+- shared - Class lifestyle (Default: false)
+
+Example:
+```xml
+<?xml version="1.0"?>
+<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:Event/etc/events.xsd">
+    <event name="cms_block_save_before">
+        <observer name="myObserverName" instance="MyCompany\MyModule\Observer\MyObserver" />
+    </event>
+    <event name="cms_block_save_commit_after">
+        <observer name="myObserverName2" instance="MyCompany\MyModule\Observer\AnotherObserver" disabled="true" shared="true"/>
+    </event>
+</config>
+```
+
+Observer class should be placed in the <module-root>/Observer directory and implement
+[Magento\Framework\Event\ObserverInterface](https://github.com/magento/magento2/blob/2.2-develop/lib/internal/Magento/Framework/Event/ObserverInterface.php)
+interface.
+
+```php
+<?php
+
+class MyObserver implements \Magento\Framework\Event\ObserverInterface
+{
+    public function execute(\Magento\Framework\Event\Observer $observer)
+    {
+        $order = $observer->getEvent()->getData('order'); // $observer->getEvent()->getOrder();
+        // observer code...
+    }
+}
+```
+
+### Dispatching events
 
-- before sortOrder=10, before sortOrder=20, before sortOrder=30 ...
-- before and around (first half) called together for same plugin!
-- around (second half) and after called together for same plugin!
+Events dispatch by [Magento\Framework\Event\Manager](https://github.com/magento/magento2/blob/2.2-develop/lib/internal/Magento/Framework/Event/Manager.php) class
+that implement [Magento\Framework\Event\ManagerInterface](https://github.com/magento/magento2/blob/2.2-develop/lib/internal/Magento/Framework/Event/ManagerInterface.php) interface:
+> dispatch($eventName, array $data = []);
 
 Example:
+> $this->eventManager->dispatch('cms_page_prepare_save', ['page' => $model, 'request' => $this->getRequest()]);
 
-- pluginA.beforeMethod, pluginA.aroundMethod first half
-- pluginB.beforeMethod, pluginB.aroundMethod first half
-- pluginC.beforeMethod, `____________________
-- ____________________, pluginD.aroundMethod first half
-- method()
-- ____________________, pluginD.aroundMethod second half
-- pluginC.afterMethod , ________________________________
-- pluginB.aroundMethod second half, pluginB.afterMethod
-- pluginA.aroundMethod second half, pluginA.afterMethod
+###### Links
+- [Magento DevDocs - Events and observers](https://devdocs.magento.com/guides/v2.2/extension-dev-guide/events-and-observers.html)
+- [Magento DevDocs - Observers Best Practices](https://devdocs.magento.com/guides/v2.2/ext-best-practices/extension-coding/observers-bp.html)
+
+
+## Scheduled jobs
 
 ### Demonstrate how to configure a scheduled job
 
-cron_groups.xml - store view scope:
+`cron_groups.xml` - store view scope:
 
 - default (no separate process)
 - index - mview, targetrule
@@ -88,10 +145,14 @@ TODO: find out
 what is setup:cron:run?
 TODO: find out
 
+###### Links
+- [Magento DevDocs - Configure a custom cron job and cron group (tutorial)](https://devdocs.magento.com/guides/v2.2/config-guide/cron/custom-cron-tut.html)
+- [Magento DevDocs - Custom cron job and cron group reference](https://devdocs.magento.com/guides/v2.2/config-guide/cron/custom-cron-ref.html)
+
 
 ### Identify the function and proper use of automatically available events
 
-Model events \Magento\Framework\Model\AbstractModel:
+Model events [\Magento\Framework\Model\AbstractModel](https://github.com/magento/magento2/blob/2.2-develop/lib/internal/Magento/Framework/Model/AbstractModel.php):
 
 - `model_load_before`, `{$_eventPrefix}_load_before`
 - `model_load_after`, `{$_eventPrefix}_load_after`
@@ -102,21 +163,24 @@ Model events \Magento\Framework\Model\AbstractModel:
 - `model_delete_after`, `{$_eventPrefix}_delete_after`
 - `model_delete_commit_after`, `{$_eventPrefix}_delete_commit_after`
 
-Flat collection events \Magento\Framework\Model\ResourceModel\Db\Collection\AbstractCollection:
+Flat collection events [\Magento\Framework\Model\ResourceModel\Db\Collection\AbstractCollection](https://github.com/magento/magento2/blob/2.2-develop/lib/internal/Magento/Framework/Model/ResourceModel/Db/Collection/AbstractCollection.php):
 
 - `core_collection_abstract_load_before`, `{_eventPrefix}_load_before`
 - `core_collection_abstract_load_after`, `{_eventPrefix}_load_after`
 
 only if `_eventPrefix` and `_eventObject` defined: `{prefix}_load_before`, `{prefix}_load_after`
 
-EAV collection events \Magento\Eav\Model\Entity\Collection\AbstractCollection:
+EAV collection events [\Magento\Eav\Model\Entity\Collection\AbstractCollection](https://github.com/magento/magento2/blob/2.2-develop/app/code/Magento/Eav/Model/Entity/Collection/AbstractCollection.php):
 
 - eav_collection_abstract_load_before
 
-\Magento\Framework\Model\AbstractModel:
+[\Magento\Framework\Model\AbstractModel](https://github.com/magento/magento2/blob/2.2-develop/lib/internal/Magento/Framework/Model/AbstractModel.php):
 
 - _eventObject = 'object'
 - _eventPrefix = 'core_abstract', e.g. 'catalog_category'
 - _getEventData() - 'data_object' + $_eventObject
 - `model_load_before` (object, field=null, value=ID)
 - `{_eventPrefix}_load_before`, e.g. `catalog_category_load_before` (object, field, value, data_object, category)
+
+###### Links
+- [Cyrill Schumacher's Blog - List of all dispatched events](https://cyrillschumacher.com/magento-2.2-list-of-all-dispatched-events/)