Organizing services with tags

One useful configuration feature that can be used in the service settings is a tag. It does not alter a service in any way, rather it provides properties that can be used in services for better organization.

For example, open the services.yml file in AppBundle and look at the configuration that SonataUserBundle creates to address the user profile edit form:

services:
   mava_user.profile.form.type:
      class: AppBundle\Form\ProfileType
      tags:
        - { name: form.type, alias: mava_user_profile }

Now open the config.yml file and scroll down to sonata_user:

sonata_user:
    security_acl: true
    manager_type: orm
    profile:
         form:
             type:    mava_user_profile

As you can see, Sonata uses tags to address the Profile Edit form for users. In other words, the alias in the tags parameter defines the name for the form type that is used to edit profile information for users. The same alias value is used in the ProfileType class in the form...