Debug Service Container Using Console Command in Symfony 7

Symfony includes numerous pre-built commands designed for debugging various components of an application. Symfony relies heavily on its service container to manage and organize various components of the application. The service container acts as a centralized hub for handling dependencies and services. However, when dealing with complex applications, debugging and understanding the services registered in the container can be challenging. This tutorial explains how to debug service container using console command in Symfony 7.

All services

The debug:container command provides a comprehensive overview of the services registered in the Symfony application. Basic usage:

php bin/console debug:container

Running this command without any additional options will display a list of all services registered in the container. This list includes service IDs and class names. Output example:

 ------------------------------------ -------------------------------
  Service ID                           Class name
 ------------------------------------ -------------------------------
  App\Command\TestCommand              App\Command\TestCommand
  App\Controller\TestController        App\Controller\TestController
  App\Controller\TwigController        App\Controller\TwigController
  App\Kernel                           alias for "kernel"
  App\Service\TestService              App\Service\TestService
  Psr\Cache\CacheItemPoolInterface     alias for "cache.app"
  Psr\Clock\ClockInterface             alias for "clock"
...

Specific service

To display details of a specific service, provide its ID:

php bin/console debug:container serializer

This command will provide detailed information about the specified service, including its class, tags, and other information.

 ---------------- ---------------------------------------------------------------------
  Option           Value
 ---------------- ---------------------------------------------------------------------
  Service ID       debug.serializer
  Class            Symfony\Component\Serializer\Debug\TraceableSerializer
  Tags             container.decorator (id: serializer, inner: debug.serializer.inner)
  Public           no
  Synthetic        no
  Lazy             no
  Shared           yes
  Abstract         no
  Autowired        no
  Autoconfigured   no

Service tags

Utilize the --tags option to see publicly accessible services grouped by their respective tags:

php bin/console debug:container --tags

Output example:

"cache.pool" tag
----------------

 * cache.app
 * cache.system
 * cache.validator
...

"cache.pool.clearer" tag
------------------------

 * cache.default_clearer
 * cache.system_clearer
 * cache.global_clearer
...

Container parameters

Use the --parameters option to showcase all parameters within the container:

php bin/console debug:container --parameters

Output exmaple:

 ---------------------------- ---------------------------------
  Parameter                    Value
 ---------------------------- ---------------------------------
...
  kernel.charset                     UTF-8
  kernel.container_class             App_KernelDevDebugContainer
  kernel.debug                       true
  kernel.default_locale              en
  kernel.enabled_locales             []
  kernel.environment                 dev
  kernel.error_controller            error_controller
...

Deprecations

To see deprecations generated during the compilation of the container and cache warm up, use the --deprecations option:

php bin/console debug:container --deprecations

If continuous integration is used, recommended adding debug:container --deprecations command to the list of commands which executed on each build.