Breaking: #110319 - Encryption key is checked before ext_localconf.php loading 

Description 

\TYPO3\CMS\Core\Core\Bootstrap verifies that $GLOBALS['TYPO3_CONF_VARS']['SYS']['encryptionKey'] is not empty and throws a \RuntimeException otherwise. This check has been moved to run before the ext_localconf.php files of all active extensions are loaded. Previously it ran afterwards, and additionally after $GLOBALS['TCA'] had been populated.

The encryption key is part of the system configuration and is used for security-relevant functionality. It must therefore be in place before any extension code is executed during bootstrap.

In addition, $GLOBALS['TCA'] is now assigned after TcaSchemaFactory->load() has been called, so consumers can not observe a state where the global array is populated but the schema information is not yet available.

Impact 

Installations that set $GLOBALS['TYPO3_CONF_VARS']['SYS']['encryptionKey'] from within an ext_localconf.php file now run into the "TYPO3 Encryption Key is empty" exception, as the check is executed before the file is evaluated.

Code within ext_localconf.php files can not rely on $GLOBALS['TCA'] being available anymore - which was never a guaranteed state, as ext_localconf.php files are loaded before TCA is built. This is unchanged, but the assignment now happens later within the bootstrap.

Affected installations 

Installations that populate the encryption key at runtime from an ext_localconf.php file, for instance by reading it from an environment variable or an external secret store.

Migration 

Set the encryption key in the system configuration, either directly in config/system/settings.php or in config/system/additional.php, both of which are evaluated before the check:

$GLOBALS['TYPO3_CONF_VARS']['SYS']['encryptionKey'] = getenv('TYPO3_ENCRYPTION_KEY');