Properly load roles for external backend user

[sukhwinder33445]

fixes #5464

Bootstrap: Module Loading and Authentication Order:

First, bootstrap->loadEnabledModules() is executed. Then the authentication configuration (authentication.ini) is loaded and initialized via bootstrap->setupUserBackendFactory(). Only after these steps, the login form is evaluated, and the user is authenticated.

The problem is caused by the call to IcingadbSupport::useIcingaDbAsBackend() in the modules’ run.php file.

When bootstrap->loadEnabledModules() loads a module, its run.php file is executed immediately. The call to IcingadbSupport::useIcingaDbAsBackend() triggers the following call chain: hasPermission() -> isAuthenticated() -> authExternal().

Normally, modules are loaded without an authenticated user because this call chain returns false. However, when an external user logs in, authExternal() marks the user as authenticated by calling setAuthenticated().

At this point, UserBackend::$backends is not yet initialized. Because of this, user groups and roles cannot be loaded.

Icinga Web 2 shows the following error:

NOTICE: PHP message: icingaweb2: ERROR - Can't get group memberships for user 'user' from backend 'auth_ldap'. An exception was thrown: Icinga\Exception\ConfigurationError in /icingaweb2/library/Icinga/Authentication/User/UserBackend.php:74 with message: User backends not set up. Please contact your Icinga Web administrator

[nilmerg]

Sounds like #5387 solves the linked issue as well.

[sukhwinder33445]

Yes, #5387 solves this issue.