How can I add the _locale parameter to security paths?

I managed to solve the problem like this

access_control:    ...    - { path: ^/(en|fr|es|de)/privacy$, role: IS_AUTHENTICATED_ANONYMOUSLY }

A recommendation for other answerers: I now have to enter this string (en|fr|de) into all routes manually. When I add a language I have to modifiy this string in many occurences. It would be much better if one could define a string

parameters:    languages: "(en|fr|es|de)"

And use this in the route

    - { path: ^/%languages%/privacy$, role: IS_AUTHENTICATED_ANONYMOUSLY }

But I don't think this will work.

If all your locales are 2-character ones (en|fr|es|de|...) you can use a more generic regex like this:

- { path: '^/[a-z]{2}/privacy$', role: 'IS_AUTHENTICATED_ANONYMOUSLY' }

This way you won't have to touch your security.access_control every time you add a new locale.

For locales in the form EN_en you could use something like this btw:

- { path: '^/[a-zA-Z]{2}_[a-zA-Z]{2}/privacy$', role: 'IS_AUTHENTICATED_ANONYMOUSLY' }

Nowadays (since Symfony 4.1 or later) you can define the locales in one place and use it everywhere in your application

in config/services.yaml add

parameters:    myAppName.locales: en|fr|es|de

in config/routes.yaml

cms:    prefix:   /{_locale}/    controller: App\Controller\DefaultController::index    requirements:        _locale: '%myAppName.locales%'

in config/packages/security.yaml

security:    ## .... no changes here    access_control:        - { path: ^/(%myAppName.locales%)/cms, roles: ROLE_ADMIN }