.. index:: single: Configuration
Symfony applications are configured with the files stored in the config/
directory, which has this default structure:
your-project/
├─ config/
│ ├─ packages/
│ ├─ bundles.php
│ ├─ routes.yaml
│ └─ services.yaml
├─ ...
The routes.yaml
file defines the :doc:`routing configuration </routing>`;
the services.yaml
file configures the services of the
:doc:`service container </service_container>`; the bundles.php
file enables/
disables packages in your application.
You'll be working mostly in the config/packages/
directory. This directory
stores the configuration of every package installed in your application.
Packages (also called "bundles" in Symfony and "plugins/modules" in other
projects) add ready-to-use features to your projects.
When using :ref:`Symfony Flex <symfony-flex>`, which is enabled by default in
Symfony applications, packages update the bundles.php
file and create new
files in config/packages/
automatically during their installation. For
example, this is the default file created by the "API Platform" package:
# config/packages/api_platform.yaml
api_platform:
mapping:
paths: ['%kernel.project_dir%/src/Entity']
Splitting the configuration into lots of small files is intimidating for some Symfony newcomers. However, you'll get used to them quickly and you rarely need to change these files after package installation
Tip
To learn about all the available configuration options, check out the
:doc:`Symfony Configuration Reference </reference/index>` or run the
config:dump-reference
command.
Unlike other frameworks, Symfony doesn't impose a specific format on you to configure your applications. Symfony lets you choose between YAML, XML and PHP and throughout the Symfony documentation, all configuration examples will be shown in these three formats.
There isn't any practical difference between formats. In fact, Symfony transforms and caches all of them into PHP before running the application, so there's not even any performance difference between them.
YAML is used by default when installing packages because it's concise and very readable. These are the main advantages and disadvantages of each format:
- YAML: simple, clean and readable, but not all IDEs support autocompletion and validation for it. :doc:`Learn the YAML syntax </components/yaml/yaml_format>`;
- XML:autocompleted/validated by most IDEs and is parsed natively by PHP, but sometimes it generates configuration considered too verbose. Learn the XML syntax;
- PHP: very powerful and it allows you to create dynamic configuration, but the resulting configuration is less readable than the other formats.
Symfony loads configuration files using the :doc:`Config component </components/config>`, which provides advanced features such as importing other configuration files, even if they use a different format:
.. configuration-block:: .. code-block:: yaml # config/services.yaml imports: - { resource: 'legacy_config.php' } # ignore_errors silently discards errors if the loaded file doesn't exist - { resource: 'my_config_file.xml', ignore_errors: true } # glob expressions are also supported to load multiple files - { resource: '/etc/myapp/*.yaml' } # ... .. code-block:: xml <!-- config/services.xml --> <?xml version="1.0" encoding="UTF-8" ?> <container xmlns="http://symfony.com/schema/dic/services" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://symfony.com/schema/dic/services https://symfony.com/schema/dic/services/services-1.0.xsd http://symfony.com/schema/dic/symfony https://symfony.com/schema/dic/symfony/symfony-1.0.xsd"> <imports> <import resource="legacy_config.php"/> <!-- ignore_errors silently discards errors if the loaded file doesn't exist --> <import resource="my_config_file.yaml" ignore-errors="true"/> <!-- glob expressions are also supported to load multiple files --> <import resource="/etc/myapp/*.yaml"/> </imports> <!-- ... --> </container> .. code-block:: php // config/services.php namespace Symfony\Component\DependencyInjection\Loader\Configurator; return static function (ContainerConfigurator $container) { $container->import('legacy_config.php'); // ignore_errors (3rd parameter) silently discards errors if the loaded file doesn't exist $container->import('my_config_file.xml', null, true); // glob expressions are also supported to load multiple files $container->import('/etc/myapp/*.yaml'); }; // ...
Sometimes the same configuration value is used in several configuration files.
Instead of repeating it, you can define it as a "parameter", which is like a
reusable configuration value. By convention, parameters are defined under the
parameters
key in the config/services.yaml
file:
.. configuration-block:: .. code-block:: yaml # config/services.yaml parameters: # the parameter name is an arbitrary string (the 'app.' prefix is recommended # to better differentiate your parameters from Symfony parameters). app.admin_email: 'something@example.com' # boolean parameters app.enable_v2_protocol: true # array/collection parameters app.supported_locales: ['en', 'es', 'fr'] # binary content parameters (encode the contents with base64_encode()) app.some_parameter: !!binary VGhpcyBpcyBhIEJlbGwgY2hhciAH # PHP constants as parameter values app.some_constant: !php/const GLOBAL_CONSTANT app.another_constant: !php/const App\Entity\BlogPost::MAX_ITEMS # ... .. code-block:: xml <!-- config/services.xml --> <?xml version="1.0" encoding="UTF-8" ?> <container xmlns="http://symfony.com/schema/dic/services" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:framework="http://symfony.com/schema/dic/symfony" xsi:schemaLocation="http://symfony.com/schema/dic/services https://symfony.com/schema/dic/services/services-1.0.xsd http://symfony.com/schema/dic/symfony https://symfony.com/schema/dic/symfony/symfony-1.0.xsd"> <parameters> <!-- the parameter name is an arbitrary string (the 'app.' prefix is recommended to better differentiate your parameters from Symfony parameters). --> <parameter key="app.admin_email">something@example.com</parameter> <!-- boolean parameters --> <parameter key="app.enable_v2_protocol">true</parameter> <!-- if you prefer to store the boolean value as a string in the parameter --> <parameter key="app.enable_v2_protocol" type="string">true</parameter> <!-- array/collection parameters --> <parameter key="app.supported_locales" type="collection"> <parameter>en</parameter> <parameter>es</parameter> <parameter>fr</parameter> </parameter> <!-- binary content parameters (encode the contents with base64_encode()) --> <parameter key="app.some_parameter" type="binary">VGhpcyBpcyBhIEJlbGwgY2hhciAH</parameter> <!-- PHP constants as parameter values --> <parameter key="app.some_constant" type="constant">GLOBAL_CONSTANT</parameter> <parameter key="app.another_constant" type="constant">App\Entity\BlogPost::MAX_ITEMS</parameter> </parameters> <!-- ... --> </container> .. code-block:: php // config/services.php namespace Symfony\Component\DependencyInjection\Loader\Configurator; use App\Entity\BlogPost; return static function (ContainerConfigurator $container) { $container->parameters() // the parameter name is an arbitrary string (the 'app.' prefix is recommended // to better differentiate your parameters from Symfony parameters). ->set('app.admin_email', 'something@example.com') // boolean parameters ->set('app.enable_v2_protocol', true) // array/collection parameters ->set('app.supported_locales', ['en', 'es', 'fr']) // binary content parameters (use the PHP escape sequences) ->set('app.some_parameter', 'This is a Bell char: \x07') // PHP constants as parameter values ->set('app.some_constant', GLOBAL_CONSTANT) ->set('app.another_constant', BlogPost::MAX_ITEMS); }; // ...
Caution!
When using XML configuration, the values between <parameter>
tags are
not trimmed. This means that the value of the following parameter will be
'\n something@example.com\n'
:
<parameter key="app.admin_email">
something@example.com
</parameter>
Once defined, you can reference this parameter value from any other
configuration file using a special syntax: wrap the parameter name in two %
(e.g. %app.admin_email%
):
.. configuration-block:: .. code-block:: yaml # config/packages/some_package.yaml some_package: # any string surrounded by two % is replaced by that parameter value email_address: '%app.admin_email%' # ... .. code-block:: xml <!-- config/packages/some_package.xml --> <?xml version="1.0" encoding="UTF-8" ?> <container xmlns="http://symfony.com/schema/dic/services" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:framework="http://symfony.com/schema/dic/symfony" xsi:schemaLocation="http://symfony.com/schema/dic/services https://symfony.com/schema/dic/services/services-1.0.xsd http://symfony.com/schema/dic/symfony https://symfony.com/schema/dic/symfony/symfony-1.0.xsd"> <!-- any string surrounded by two % is replaced by that parameter value --> <some-package:config email-address="%app.admin_email%"> <!-- ... --> </some-package:config> </container> .. code-block:: php // config/packages/some_package.php namespace Symfony\Component\DependencyInjection\Loader\Configurator; return static function (ContainerConfigurator $container) { $container->extension('some_package', [ // any string surrounded by two % is replaced by that parameter value 'email_address' => '%app.admin_email%', // ... ]); };
Note
If some parameter value includes the %
character, you need to escape it
by adding another %
so Symfony doesn't consider it a reference to a
parameter name:
.. configuration-block:: .. code-block:: yaml # config/services.yaml parameters: # Parsed as 'https://symfony.com/?foo=%s&bar=%d' url_pattern: 'https://symfony.com/?foo=%%s&bar=%%d' .. code-block:: xml <!-- config/services.xml --> <parameters> <parameter key="url_pattern">http://symfony.com/?foo=%%s&bar=%%d</parameter> </parameters> .. code-block:: php // config/services.php namespace Symfony\Component\DependencyInjection\Loader\Configurator; return static function (ContainerConfigurator $container) { $container->parameters() ->set('url_pattern', 'http://symfony.com/?foo=%%s&bar=%%d'); };
Configuration parameters are very common in Symfony applications. Some packages
even define their own parameters (e.g. when installing the translation package,
a new locale
parameter is added to the config/services.yaml
file).
.. seealso:: Later in this article you can read how to :ref:`get configuration parameters in controllers and services <configuration-accessing-parameters>`.
.. index:: single: Environments; Introduction
You have just one application, but whether you realize it or not, you need it to behave differently at different times:
- While developing, you want to log everything and expose nice debugging tools;
- After deploying to production, you want that same application to be optimized for speed and only log errors.
The files stored in config/packages/
are used by Symfony to configure the
:doc:`application services </service_container>`. In other words, you can change
the application behavior by changing which configuration files are loaded.
That's the idea of Symfony's configuration environments.
A typical Symfony application begins with three environments: dev
(for local
development), prod
(for production servers) and test
(for
:doc:`automated tests </testing>`). When running the application, Symfony loads
the configuration files in this order (the last files can override the values
set in the previous ones):
config/packages/*.yaml
(and*.xml
and*.php
files too);config/packages/<environment-name>/*.yaml
(and*.xml
and*.php
files too);config/packages/services.yaml
(andservices.xml
andservices.php
files too);
Take the framework
package, installed by default, as an example:
- First,
config/packages/framework.yaml
is loaded in all environments and it configures the framework with some options; - In the prod environment, nothing extra will be set as there is no
config/packages/prod/framework.yaml
file; - In the dev environment, there is no file either (
config/packages/dev/framework.yaml
does not exist). - In the test environment, the
config/packages/test/framework.yaml
file is loaded to override some of the settings previously configured inconfig/packages/framework.yaml
.
In reality, each environment differs only somewhat from others. This means that
all environments share a large base of common configuration, which is put in
files directly in the config/packages/
directory.
.. seealso:: See the ``configureContainer()`` method of :doc:`the Kernel class </configuration/front_controllers_and_kernel>` to learn everything about the loading order of configuration files.
Symfony applications come with a file called .env
located at the project
root directory. This file is used to define the value of environment variables
and it's explained in detail :ref:`later in this article <config-dot-env>`.
Open the .env
file (or better, the .env.local
file if you created one)
and edit the value of the APP_ENV
variable to change the environment in
which the application runs. For example, to run the application in production:
# .env (or .env.local)
APP_ENV=prod
This value is used both for the web and for the console commands. However, you
can override it for commands by setting the APP_ENV
value before running them:
# Use the environment defined in the .env file
$ php bin/console command_name
# Ignore the .env file and run this command in production
$ APP_ENV=prod php bin/console command_name
The default three environments provided by Symfony are enough for most projects,
but you can define your own environments too. For example, this is how you can
define a staging
environment where the client can test the project before
going to production:
- Create a configuration directory with the same name as the environment (in
this case,
config/packages/staging/
); - Add the needed configuration files in
config/packages/staging/
to define the behavior of the new environment. Symfony loads theconfig/packages/*.yaml
files first, so you only need to configure the differences to those files; - Select the
staging
environment using theAPP_ENV
env var as explained in the previous section.
Tip
It's common for environments to be similar to each other, so you can
use symbolic links between config/packages/<environment-name>/
directories to reuse the same configuration.
Using environment variables (or "env vars" for short) is a common practice to configure options that depend on where the application is run (e.g. the database credentials are usually different in production versus your local machine). If the values are sensitive, you can even :doc:`encrypt them as secrets </configuration/secrets>`.
You can reference environment variables using the special syntax
%env(ENV_VAR_NAME)%
. The values of these options are resolved at runtime
(only once per request, to not impact performance).
This example shows how you could configure the database connection using an env var:
.. configuration-block:: .. code-block:: yaml # config/packages/doctrine.yaml doctrine: dbal: # by convention the env var names are always uppercase url: '%env(resolve:DATABASE_URL)%' # ... .. code-block:: xml <!-- config/packages/doctrine.xml --> <?xml version="1.0" encoding="UTF-8" ?> <container xmlns="http://symfony.com/schema/dic/services" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:doctrine="http://symfony.com/schema/dic/doctrine" xsi:schemaLocation="http://symfony.com/schema/dic/services https://symfony.com/schema/dic/services/services-1.0.xsd http://symfony.com/schema/dic/doctrine https://symfony.com/schema/dic/doctrine/doctrine-1.0.xsd"> <doctrine:config> <!-- by convention the env var names are always uppercase --> <doctrine:dbal url="%env(resolve:DATABASE_URL)%"/> </doctrine:config> </container> .. code-block:: php // config/packages/doctrine.php namespace Symfony\Component\DependencyInjection\Loader\Configurator; return static function (ContainerConfigurator $container) { $container->extension('doctrine', [ 'dbal' => [ // by convention the env var names are always uppercase 'url' => '%env(resolve:DATABASE_URL)%', ] ]); };
.. seealso:: The values of env vars can only be strings, but Symfony includes some :doc:`env var processors </configuration/env_var_processors>` to transform their contents (e.g. to turn a string value into an integer).
To define the value of an env var, you have several options:
- :ref:`Add the value to a .env file <config-dot-env>`;
- :ref:`Encrypt the value as a secret <configuration-secrets>`;
- Set the value as a real environment variable in your shell or your web server.
Tip
Some hosts - like SymfonyCloud - offer easy utilities to manage env vars in production.
Caution!
Beware that dumping the contents of the $_SERVER
and $_ENV
variables
or outputting the phpinfo()
contents will display the values of the
environment variables, exposing sensitive information such as the database
credentials.
The values of the env vars are also exposed in the web interface of the :doc:`Symfony profiler </profiler>`. In practice this shouldn't be a problem because the web profiler must never be enabled in production.
Instead of defining env vars in your shell or your web server, Symfony provides
a convenient way to define them inside a .env
(with a leading dot) file
located at the root of your project.
The .env
file is read and parsed on every request and its env vars are added
to the $_ENV
& $_SERVER
PHP variables. Any existing env vars are never
overwritten by the values defined in .env
, so you can combine both.
For example, to define the DATABASE_URL
env var shown earlier in this article,
you can add:
# .env
DATABASE_URL="mysql://db_user:db_password@127.0.0.1:3306/db_name"
This file should be committed to your repository and (due to that fact) should only contain "default" values that are good for local development. This file should not contain production values.
In addition to your own env vars, this .env
file also contains the env vars
defined by the third-party packages installed in your application (they are
added automatically by :ref:`Symfony Flex <symfony-flex>` when installing packages).
Add comments by prefixing them with #
:
# database credentials
DB_USER=root
DB_PASS=pass # this is the secret password
Use environment variables in values by prefixing variables with $
:
DB_USER=root
DB_PASS=${DB_USER}pass # include the user as a password prefix
Caution!
The order is important when some env var depends on the value of other env
vars. In the above example, DB_PASS
must be defined after DB_USER
.
Moreover, if you define multiple .env
files and put DB_PASS
first,
its value will depend on the DB_USER
value defined in other files
instead of the value defined in this file.
Define a default value in case the environment variable is not set:
DB_USER=
DB_PASS=${DB_USER:-root}pass # results in DB_PASS=rootpass
Embed commands via $()
(not supported on Windows):
START_TIME=$(date)
Caution!
Using $()
might not work depending on your shell.
Tip
As a .env
file is a regular shell script, you can source
it in
your own shell scripts:
$ source .env
If you need to override an environment value (e.g. to a different value on your
local machine), you can do that in a .env.local
file:
# .env.local
DATABASE_URL="mysql://root:@127.0.0.1:3306/my_database_name"
This file should be ignored by git and should not be committed to your repository.
Several other .env
files are available to set environment variables in just
the right situation:
.env
: defines the default values of the env vars needed by the application;.env.local
: overrides the default values for all environments but only on the machine which contains the file. This file should not be committed to the repository and it's ignored in thetest
environment (because tests should produce the same results for everyone);.env.<environment>
(e.g..env.test
): overrides env vars only for one environment but for all machines (these files are committed);.env.<environment>.local
(e.g..env.test.local
): defines machine-specific env var overrides only for one environment. It's similar to.env.local
, but the overrides only apply to one environment.
Real environment variables always win over env vars created by any of the
.env
files.
The .env
and .env.<environment>
files should be committed to the
repository because they are the same for all developers and machines. However,
the env files ending in .local
(.env.local
and .env.<environment>.local
)
should not be committed because only you will use them. In fact, the
.gitignore
file that comes with Symfony prevents them from being committed.
Caution!
Applications created before November 2018 had a slightly different system,
involving a .env.dist
file. For information about upgrading, see:
:doc:`configuration/dot-env-changes`.
In production, the .env
files are also parsed and loaded on each request. So
the easiest way to define env vars is by deploying a .env.local
file to your
production server(s) with your production values.
To improve performance, you can optionally run the dump-env
command (available
in :ref:`Symfony Flex <symfony-flex>` 1.2 or later):
# parses ALL .env files and dumps their final values to .env.local.php
$ composer dump-env prod
After running this command, Symfony will load the .env.local.php
file to
get the environment variables and will not spend time parsing the .env
files.
Tip
Update your deployment tools/workflow to run the dump-env
command after
each deploy to improve the application performance.
Instead of defining a real environment variable or adding it to a .env
file,
if the value of a variable is sensitive (e.g. an API key or a database password),
you can encrypt the value using the :doc:`secrets management system </configuration/secrets>`.
Regardless of how you set environment variables, you can see a full list with their values by running:
$ php bin/console debug:container --env-vars
---------------- ----------------- ---------------------------------------------
Name Default value Real value
---------------- ----------------- ---------------------------------------------
APP_SECRET n/a "471a62e2d601a8952deb186e44186cb3"
FOO "[1, "2.5", 3]" n/a
BAR null n/a
---------------- ----------------- ---------------------------------------------
# you can also filter the list of env vars by name:
$ php bin/console debug:container --env-vars foo
# run this command to show all the details for a specific env var:
$ php bin/console debug:container --env-var=FOO
Controllers and services can access all the configuration parameters. This includes both the :ref:`parameters defined by yourself <configuration-parameters>` and the parameters created by packages/bundles. Run the following command to see all the parameters that exist in your application:
$ php bin/console debug:container --parameters
In controllers extending from the :ref:`AbstractController <the-base-controller-class-services>`,
use the getParameter()
helper:
// src/Controller/UserController.php namespace App\Controller; use Symfony\Bundle\FrameworkBundle\Controller\AbstractController; class UserController extends AbstractController { // ... public function index() { $projectDir = $this->getParameter('kernel.project_dir'); $adminEmail = $this->getParameter('app.admin_email'); // ... } }
In services and controllers not extending from AbstractController
, inject
the parameters as arguments of their constructors. You must inject them
explicitly because :doc:`service autowiring </service_container/autowiring>`
doesn't work for parameters:
.. configuration-block:: .. code-block:: yaml # config/services.yaml parameters: app.contents_dir: '...' services: App\Service\MessageGenerator: arguments: $contentsDir: '%app.contents_dir%' .. code-block:: xml <!-- config/services.xml --> <?xml version="1.0" encoding="UTF-8" ?> <container xmlns="http://symfony.com/schema/dic/services" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://symfony.com/schema/dic/services https://symfony.com/schema/dic/services/services-1.0.xsd"> <parameters> <parameter key="app.contents_dir">...</parameter> </parameters> <services> <service id="App\Service\MessageGenerator"> <argument key="$contentsDir">%app.contents_dir%</argument> </service> </services> </container> .. code-block:: php // config/services.php namespace Symfony\Component\DependencyInjection\Loader\Configurator; use App\Service\MessageGenerator; return static function (ContainerConfigurator $container) { $container->parameters() ->set('app.contents_dir', '...'); $container->services() ->get(MessageGenerator::class) ->arg('$contentsDir', '%app.contents_dir%'); };
If you inject the same parameters over and over again, use the
services._defaults.bind
option instead. The arguments defined in that option are
injected automatically whenever a service constructor or controller action
defines an argument with that exact name. For example, to inject the value of the
:ref:`kernel.project_dir parameter <configuration-kernel-project-directory>`
whenever a service/controller defines a $projectDir
argument, use this:
.. configuration-block:: .. code-block:: yaml # config/services.yaml services: _defaults: bind: # pass this value to any $projectDir argument for any service # that's created in this file (including controller arguments) $projectDir: '%kernel.project_dir%' # ... .. code-block:: xml <!-- config/services.xml --> <?xml version="1.0" encoding="UTF-8" ?> <container xmlns="http://symfony.com/schema/dic/services" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://symfony.com/schema/dic/services https://symfony.com/schema/dic/services/services-1.0.xsd"> <services> <defaults autowire="true" autoconfigure="true" public="false"> <!-- pass this value to any $projectDir argument for any service that's created in this file (including controller arguments) --> <bind key="$projectDir">%kernel.project_dir%</bind> </defaults> <!-- ... --> </services> </container> .. code-block:: php // config/services.php namespace Symfony\Component\DependencyInjection\Loader\Configurator; use App\Controller\LuckyController; use Psr\Log\LoggerInterface; use Symfony\Component\DependencyInjection\Reference; return static function (ContainerConfigurator $container) { $container->services() ->set(LuckyController::class) ->public() ->args([ // pass this value to any $projectDir argument for any service // that's created in this file (including controller arguments) '$projectDir' => '%kernel.project_dir%', ]); };
.. seealso:: Read the article about :ref:`binding arguments by name and/or type <services-binding>` to learn more about this powerful feature.
Finally, if some service needs access to lots of parameters, instead of injecting each of them individually, you can inject all the application parameters at once by type-hinting any of its constructor arguments with the :class:`Symfony\\Component\\DependencyInjection\\ParameterBag\\ContainerBagInterface`:
// src/Service/MessageGenerator.php namespace App\Service; // ... use Symfony\Component\DependencyInjection\ParameterBag\ContainerBagInterface; class MessageGenerator { private $params; public function __construct(ContainerBagInterface $params) { $this->params = $params; } public function someMethod() { // get any container parameter from $this->params, which stores all of them $sender = $this->params->get('mailer_sender'); // ... } }
Congratulations! You've tackled the basics of Symfony. Next, learn about each part of Symfony individually by following the guides. Check out:
- :doc:`/forms`
- :doc:`/doctrine`
- :doc:`/service_container`
- :doc:`/security`
- :doc:`/mailer`
- :doc:`/logging`
And all the other topics related to configuration:
.. toctree:: :maxdepth: 1 :glob: configuration/*