Part-DB-server/config/routes/attributes.yaml

controllers:
    resource:
        path: ../../src/Controller/
        namespace: App\Controller
    type: attribute
    prefix: '{_locale}'
    # OAuth2 protocol endpoints (client registration, discovery metadata) must live at fixed,
    # spec-mandated paths with no locale prefix - see config/routes/oauth_server_controllers.yaml.
    exclude: '../../src/Controller/OAuth/*'

    defaults:
        _locale: '%kernel.default_locale%'
    requirements:
        # Match only locales like de_DE or de
        _locale: "^[a-z]{2}(_[A-Z]{2})?$"

oauth_server_controllers:
    resource:
        path: ../../src/Controller/OAuth/
        namespace: App\Controller\OAuth
    type: attribute

kernel:
    resource: ../../src/Kernel.php
    type: attribute