Internal Config Loading

The internal config loading process in n98-magerun2 is robust and extensible, allowing configuration at multiple levels. The process is orchestrated by the Application class and relies on Config, ConfigLocator, and ConfigurationLoader to discover, load, and merge configuration files, ensuring that user and project-specific settings are respected.

Technical Overview: Internal Config Loading Process

n98-magerun2 uses a layered configuration system, loading and merging config files from multiple sources. The process is managed by several key classes and methods:

Key Classes and Methods

• N98\Magento\Application\Config: Central class for managing configuration data. Handles loading, merging, and providing access to config values.
• N98\Magento\Application\ConfigLocator: Responsible for discovering config files in user, project, and stop-file locations.
• N98\Magento\Application\ConfigInfo: Represents metadata about each config file (type and path).
• N98\Magento\Application\ConfigurationLoader: Handles the actual loading and merging of config files in two stages.
• N98\Magento\Application: The main application class, orchestrates the config loading process in its init() method.

Config Loading Process

1. Partial Config Load (Stage One)

   • In Application::init(), a Config object is created and Config::loadPartialConfig() is called.
   • This loads basic config files (e.g., dist, system, user) to determine initial settings and command aliases.

2. Magento Detection

   • The application attempts to detect the Magento root directory, which may affect which config files are loaded (e.g., project config in app/etc/).

3. Full Config Load (Stage Two)

   • After Magento detection, ConfigurationLoader::loadStageTwo() is called.
   • This loads additional config files, such as project and stop-file configs, using the discovered Magento root.
   • The ConfigLocator is used to find the correct file paths for user, project, and stop-file configs.

4. Config Merging

   • All discovered config files are merged in a specific order:
     1. Dist (default)
     2. System
     3. User
     4. Plugin
     5. Project
     6. Stop-file (if present)
   • Later files override earlier ones, allowing for user and project-specific customizations.

5. Config Access and Usage

   • The merged config is available via the Config object, which provides methods to retrieve config values and register custom commands, helpers, and autoloaders.

Example: Config Discovery

• User Config: Located in the user's home directory (e.g., ~/.n98-magerun2.yaml). Discovered by ConfigLocator::getUserConfigFile().
• Project Config: Located in the Magento root at app/etc/n98-magerun2.yaml. Discovered by ConfigLocator::getProjectConfigFile().
• Stop-File Config: Optionally, a config file in the directory containing a stop file. Discovered by ConfigLocator::getStopFileConfigFile().