Magento

General

• Magento 2 was released in 2015
• Variants
  • Magento Open Source (before 2018 Magento Community Edition)
  • Magento Commerce (before Magento Enterprise Edition)
  • Differences see here
• object oriented
• uses design patterns (GoF) like GRASP, but in an individual manner
• uses MVC with thin controller approach (Business Logic is mainly in Model or View), View is configured by layout XML
• user groups:
  • web business user
  • system administrator
  • web API user

Technology

• PHP 7 and coding standards PSR-0 to PSR-4
• MySQL 5.6
• Apache 2.2, 2.4
• PHP Composer
• HTML5
• LESS CSS
• jQuery
• RequireJS
• Zend Framework
• Symfony
• Magento Testing Framework
• ...

Coding Standards

PHP

• PSR-1
  • each sub-word should be capitalised in both instances, with classes having an initial upper-case letter (StudlyCaps) and methods an initial lower-case letter (camelCase)
  • Class constants MUST be declared in all upper case with underscore separators
• PSR-2
• PSR-4

Architecture

• layers:
  • presentation
  • service
  • domain
  • persistence

Persistence Layer

• consists of
  • layouts
  • blocks
  • templates
  • controllers

Service Layer

• bridges presentation and domain layer
• provides service contracts (PHP interface, REST/SOAP API): a service contract is a set of PHP interfaces that is defined by a module. This contract comprises data interfaces and service interfaces.

Business Layer

• implementents the business logic
• modul communication via event observers, pluginsa and di.xml

Persistance Layer

• implements CRUD (create, read, update, delete) requests
• there are 3 types of classes:
  • model classes: don't contain any code for communicating with the DB
  • resource classes: read and write to the DB
  • collection classes: array of individual model instances which implement IteratorAggregate and Countable
• models and resources are often seen as an unified thing called model
• there are simple resource model and Entity-Attribute-Value (EAV) resource model

Modules

A Magento Module is a directory with subdirectories containing blocks, controllers, helpers, and models that are needed to create a specific store feature. It has a life cycle that allows them to be installed, deleted, or disabled. Modules typically live in the vendor directory of a Magento installation, in a directory with the following PSR-0 compliant format: vendor/<VENDORNAME>/<TYPE>-<MODULENAME>, where <TYPE> can be one of the following values:

• module - for modules (module-customer-import-export)
• theme - for frontend and admin themes (theme-frontend-luma or theme-adminhtml-backend)
• language - for language packs (language-de_de)

or you can just create the app/code/<VENDORNAME>/<TYPE>-<MODULENAME> directory (<MODULE_ROOT_DIR>) and the required directories within it. Inside the <MODULE_ROOT_DIR> you will find all the code related to this module:

• <MODULE_ROOT_DIR>/registration.php

module.xml

• <MODULE_ROOT_DIR>/etc/module.xml declares the module by configuration like name, version, dependencies, ...

...
<module name="<VENDORNAME>_<MODULENAME>" setup_version="<VERSION>">
  <sequence>
    <module name ="<VENDORNAME>_<MODULENAME>" />
    <DEPENDENCY_LIST>
  </sequence>
</module>

config.xml

• <MODULE_ROOT_DIR>/etc/config.xml
• the values of the attributes are somehow the 'reset to factory values', they are used if no corresponding DB entry is found in core_config_data with path=[carriers|???]/<CODENAME>/<ATTRIBUTE>

...
<default>
  <carriers> // carries is for shipping, other options ???
    <<CODENAME>>  // same as $_code property in model class
      <<CONFIG_ATTRIBUTE>><SYSTEM_DEFAULT_VALUE></<CONFIG_ATTRIBUTE>> // name used in system.xml and in code
      <active><0|???></active> // active or not
      <model>
        <FILEPATH_FILENAME_WO_EXT> // model class with same name as FILENAME
      </model>
      <title><TEXT></title>display in the frontend
      <sallowspecific><0|1></sallowspecific>   // for carries: available in all countries or only in selected countries
      <sort_order><sort_order>
    </<CODENAME>>
  </carriers>
</default>

system.xml

• <MODULE_ROOT_DIR>/etc/adminhtml/system.xml
• used for Magento system configuration

...
<system>
  ...
  <section id=["carriers"|???]>
     ...
     <group>
       <label><LABEL></label>
       <field id="<CONFIG_ATTRIBUTE>">
          <label><LABEL></label>
          [<validate><VALIDATE></validate>]
          [<source_model><MODEL></source_model>]
          [<frontend_class><CLASS></frontend_class>]
          [<comment><COMMENT></comment>]
       </field>
       ...
     </group>
  </section>
</system>

• all elements below <system> have the following attributes:
  • showInDefault=["0"|"1"], showInWebsite=["0"|"1"] and showInStore=["0"|"1"] which control whether the element is shown in the corresponding configuration level.

model classes

• module declaration in <MODULE_ROOT_DIR>/Model/ Not Validated, probably wrong: The _construct() method is implemented by Magento in some classes and it's called automatically inside the __construct function declaration, so if you are extending a Magento class like a Model you can use it to perform some stuff after object creation. In a Resource Model or Model Class you should define a _construct() method in order to define the table and the primary_key.

Simple Model

• <MODULE_ROOT_DIR>/Model/[<SUB_DIR>/]<MODELNAME>.php

class <MODELNAME> extends \Magento\Framework\Model\AbstractModel
{
  protected function _construct()
  {
    $this->_init('<VENDORNAME>\<MODULENAME>\Model\ResourceModel\<MODELNAME>'); // tells Magento about resource class

• resource declaration in <MODULE_ROOT_DIR>/Model/ResourceModel/<MODELNAME>.php

class <MODELNAME> extends \Magento\Framework\Model\ResourceModel\Db\AbstractDb
{
  protected function _construct() 
  {
    $this->_init('<TABLENAME>', '<PRIMARY_KEY_COLUMN>');

• create collection in <MODULE_ROOT_DIR>/Model/ResourceModel/<MODELNAME>/Collection.php

class Collection extends \Magento\Framework\Model\ResourceModel\Db\Collection\AbstractCollection
{
  protected function _construct()
  {
     $this->_init('<FULL_MODEL_CLASSNAME>', '<FULL_RESOURCE_CLASSNAME>');

EAV Model

• <MODULE_ROOT_DIR>/Model/<MODELNAME>.php

class <MODELNAME> extends \Magento\Framework\Model\AbstractModel
{
  protected function _construct()
  {
    $this->_init('<VENDORNAME>\<MODULENAME>\Model\ResourceModel\<MODELNAME>'); // tells Magento about resource class

• resource declaration in <MODULE_ROOT_DIR>/Model/ResourceModel/<MODELNAME>.php

class <MODELNAME> extends \Magento\Framework\Model\Entity\AbstractEntity
{
  protected function _construct() 
  {
    $this->_read =
    $this->_write = 
  }

  public function getEntityType()
  {
    ...
  }

• create collection in <MODULE_ROOT_DIR>/Model/ResourceModel/<MODELNAME>/Collection.php

class Collection extends \Magento\Framework\Model\ResourceModel\Db\Collection\AbstractCollection
{
  protected function _construct()
  {
     $this->_init('<FULL_MODEL_CLASSNAME>', '<FULL_RESOURCE_CLASSNAME>');

Themes

Modules and themes are the units of customization in Magento. Themes strongly influence user experience and storefront appearance.

Caching

• located in /var/ directory

Code Generation

• Factory, Proxy and Interceptor classes are generated and stored in /var/generation/

DB Tables

• core_config_data: e.g. data from config.xml
• setup_module: all modules and their versions

Object Model

Magento\Framework\DataObject

• implements getXYZ() and setXYZ() by overriding the PHP __call magic method

Magento\Quote\Model\Quote\Address\RateRequest

This class contains all information about items in cart/quote, weight, shipping address and so on.

Magento\Shipping\Model\Carrier\AbstractCarrier

Base class for shipping with major methods for shipping models.

Directory Structure

• /app/code: for local developed modules
• /app/design/frontend: for storefront themes
• /app/design/adminhtml: for admin themes
• /app/i18n: for language packages
• /var/generation: contains only? generated files
• /var/?: cached infos

Operations

Commands

<MAGENTO_INSTALL_DIR>\bin\php magento module:status
<MAGENTO_INSTALL_DIR>\bin\php magento module:enable <MODULE_NAME>
<MAGENTO_INSTALL_DIR>\bin\php magento setup:upgrade

<MAGENTO_INSTALL_DIR>\bin\php magento deploy:mode:show
<MAGENTO_INSTALL_DIR>\bin\php magento deploy:mode:set developer

Magento Marketplace

• UweHeuerAccessKey
  • Public Key: 6f7df3e4e393b84da74c41937990b227
  • Private Key: a39505396b6112f47c43aa8c565cad8b

Installation

• Eon Laptop New

Sources

• Magento Marketplace
• free videos
• many Magento 2 articles
• Magento DevDocs
• PHP Developer Guide @ Magento DevDocs
• German Demo Shop
• Kindle Book 'Magento 2 Developer's Guide'