MAGETWO-64602: Sync config file with DB: Validation

Author: Bohdan Korablov

app/code/Magento/Deploy/Model/DeploymentConfig/DataCollector.php

@@ -8,9 +8,9 @@
 use Magento\Framework\App\DeploymentConfig;
 
 /**
- * Config data collector of specific sections which are defined in di.xml
+ * Config data collector of specific sections in configuration files which are defined in di.xml
  *
- * E.g.
+ * E.g., definition of sections which are needed to import:
  * ```xml
  * <type name="Magento\Deploy\Model\DeploymentConfig\ImporterPool">
  *     <arguments>
@@ -20,9 +20,22 @@
  *     </arguments>
  * </type>
  * ```
+ * Example, how sections are stored with their config data in configuration files:
+ * ```php
+ *  [
+ *      'scopes' => [...],
+ *      'system' => [...],
+ *      'themes' => [...],
+ *      ...
+ *  ]
+ * ```
+ *
  * In here we define section "scopes" and its importer Magento\Store\Model\StoreImporter.
  * The data of this section will be collected then will be used in importing process from the shared configuration
  * files to appropriate application sources.
+ *
+ * @see \Magento\Deploy\Console\Command\App\ConfigImport\Importer::import()
+ * @see \Magento\Deploy\Model\DeploymentConfig\Hash::regenerate()
  */
 class DataCollector
 {

app/code/Magento/Deploy/Model/DeploymentConfig/Hash.php

@@ -14,7 +14,10 @@
 /**
  * Saves and Retrieves deployment configuration hash.
  *
- * We need the hash of configuration data for its validation.
+ * This hash keeps version of last imported data. Hash is used to define whether data was updated
+ * and import is required.
+ *
+ * @see \Magento\Deploy\Model\DeploymentConfig\Validator::isValid()
  */
 class Hash
 {
@@ -72,10 +75,10 @@ public function __construct(
     /**
      * Updates hash in the storage.
      *
-     * The hash is updated based on configuration data from shared configuration files.
+     * The hash is generated based on data from configuration files
      *
      * @return void
-     * @throws LocalizedException is thrown when import has failed
+     * @throws LocalizedException is thrown when hash was not saved
      */
     public function regenerate()
     {

app/code/Magento/Deploy/Model/DeploymentConfig/ImporterPool.php

@@ -72,8 +72,8 @@ public function __construct(ObjectManagerInterface $objectManager, array $import
     }
 
     /**
-     * Retrieves sections from deployment configuration files which need to import into
-     * appropriate application sources.
+     * Retrieves names of sections for configuration files whose data is read from these files for import
+     * to appropriate application sources.
      *
      * @return array the list of sections
      * E.g.