How to create custom permissions on Drupal?

Drupal Permissions

Drupal allows from the UI (i.e. the admin or the back office) to manage permissions by role. For example, you can assign a "content editor" role the right to delete content of a certain type, edit it, publish it, etc. The list of possibilities is very long and also depends on the modules you have installed. Installed custom modules add permissions (administer the module, etc.). For example, if you install the webform module, you will have access to a long list of permissions such as “administer the configuration”, “edit” or “delete” a form.

The ergonomics in the UI is not always excellent because it involves ticking checkboxes in a very (too?) long list of possibilities. But it is functional and it allows to correctly manage what users have the right to do.

We can sometimes meet a limit. A role will have a permission like manage site configuration. The user will have access to features that we do not want to grant him.

A module allows you to manage these permissions more precisely: Custom Permissions

With this module, you can add specific permissions from the road without giving access to a whole set of features.

Find the route of a feature

There are several solutions. you can find the route to a core feature in:

web/core/modules/system/system.routing.yml

For example for performance management:

system.performance_settings:
  path: '/admin/config/development/performance'
  defaults:
    _form: '\Drupal\system\Form\PerformanceForm'
    _title: 'Performance'
  requirements:
    _permission: 'administer site configuration'

The route is:

system.performance_settings

For contrib modules, routes can be found in the .routing.yml file, for example for webform:

webform..routing.yml

webform.config:
  path: '/admin/structure/webform/config'
  defaults:
    _form: '\Drupal\webform\Form\AdminConfig\WebformAdminConfigFormsForm'
    _title: 'Webforms: Forms configuration'
  requirements:
    _permission: 'administer webform'

The route is:

webform.config

Use the Devel module to find a route

With the Devel module, you can use the “routes info” menu which will list the available routes.

Install the "custom permissions" module

We install the module with composer:

composer require drupal/config_perms

How to create a custom permission

Go to People > Custom permissions

Click add permission. We indicate a name for the permission. You can indicate what you want, this name is made to name your permission. Then enter the route. Then you have to activate it.

We then find this new personalized permission in the list of permissions. It can therefore be attributed to a specific role.

Example

Go to /admin/people/custom-permissions/list

Click on “add permission”

A new line appears.

Give a name like “administer basic site settings”
Specify the system.site_information_settings route

Check the “enable” box and click save.

Custom rights management

then go to the rights management page: /admin/people/permissions

There is a section with “custom permissions”.