Error when "config" attribute is set in composer.json

[QuentinDubes]

Find the error bellow:

Fatal error: Uncaught Exception: Unable to unserialize message:

( ! ) Fatal error: Uncaught RuntimeException: /vendor does not exist and could not be created. in phar:///var/www/html/vendor/mouf/mouf/composer.phar/src/Composer/Util/Filesystem.php on line 166

( ! ) RuntimeException: /vendor does not exist and could not be created. in /var/www/html/vendor/mouf/mouf/src/Mouf/Reflection/MoufReflectionProxy.php on line 208 ( ! ) Exception: Unable to unserialize message: ( ! ) Fatal error: Uncaught RuntimeException: /vendor does not exist and could not be created. in phar:///var/www/html/vendor/mouf/mouf/composer.phar/src/Composer/Util/Filesystem.php on line 166 ( ! ) RuntimeException: /vendor does not exist and could not be created. in phar:///var/www/html/vendor/mouf/mouf/composer.phar/src/Composer/Util/Filesystem.php on line 166 Call Stack # Time Memory Function Location 1 0.0026 381792 {main}( ) .../get_class_map.php:0 2 0.0208 566792 Mouf\Composer\ComposerService->getClassMap( ) .../get_class_map.php:51 3 0.0953 1365160 Composer\Util\Filesystem->ensureDirectoryExists( ) .../ComposerService.php:104 URL in error: http://api.madp.localhost:80/vendor/mouf/mouf/src/direct/get_class_map.php?selfedit=false in /var/www/html/vendor/mouf/mouf/src/Mouf/Reflection/MoufReflectionProxy.php on line 208 Call Stack Time Memory Function Location 1 0.0058 384288 {main}( ) .../get_validators_list.php:0 2 0.8641 1640072 Mouf\Moufspector::getComponentsList( ) .../get_validators_list.php:72 3 0.8689 1641832 Mouf\MoufClassExplorer->getClassMap( ) .../Moufspector.php:35 4 0.8690 1641832 Mouf\MoufClassExplorer->analyze( ) .../MoufClassExplorer.php:193 5 0.8706 1708008 Mouf\Reflection\MoufReflectionProxy::getClassMap( ) .../MoufClassExplorer.php:69