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Finish the docs for the new Access token authenticator
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‎security/access_token.rst

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How to use Access Token Authentication
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======================================
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Access tokens are commonly used in API contexts. The access token is obtained
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through an authorization server (or similar) whose role is to verify the user identity
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and receive consent before the token is issued.
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Access tokens or API tokens are commonly used as authentication mechanism
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in API contexts. The access token is a string, obtained during authentication
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(using the application or an authorization server). The access token's role
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is to verify the user identity and receive consent before the token is
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issued.
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Access Tokens can be of any kind: opaque strings, Json Web Tokens (JWT) or SAML2 (XML structures).
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Please refer to the `RFC6750`_: *The OAuth 2.0 Authorization Framework: Bearer Token Usage*.
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Access tokens can be of any kind, for instance opaque strings,
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`JSON Web Tokens (JWT)`_ or `SAML2 (XML structures)`_. Please refer to the
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`RFC6750`_: *The OAuth 2.0 Authorization Framework: Bearer Token Usage* for
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a detailed specification.
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Using the Access Token Authenticator
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------------------------------------
@@ -22,9 +26,10 @@ this is not yet the case.
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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To use the access token authenticator, you must configure a ``token_handler``.
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The token handler retrieves the user identifier from the token.
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In order to get the user identifier, implementations may need to load and validate
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the token (e.g. revocation, expiration time, digital signature...).
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The token handler receives the token from the request and returns the
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correct user identifier. To get the user identifier, implementations may
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need to load and validate the token (e.g. revocation, expiration time,
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digital signature, etc.).
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.. configuration-block::
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@@ -37,69 +42,108 @@ the token (e.g. revocation, expiration time, digital signature...).
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access_token:
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token_handler: App\Security\AccessTokenHandler
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This handler shall implement the interface
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:class:`Symfony\\Component\\Security\\Http\\AccessToken\\AccessTokenHandlerInterface`.
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In the following example, the handler will retrieve the token from a database
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using a fictive repository.
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.. configuration-block::
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.. code-block:: xml
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<!-- config/packages/security.xml -->
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<?xml version="1.0" encoding="UTF-8"?>
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<srv:container xmlns="http://symfony.com/schema/dic/security"
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xmlns:srv="http://symfony.com/schema/dic/services"
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xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
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xsi:schemaLocation="http://symfony.com/schema/dic/services
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https://symfony.com/schema/dic/services/services-1.0.xsd
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http://symfony.com/schema/dic/security
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https://symfony.com/schema/dic/security/security-1.0.xsd">
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<config>
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<firewall name="main">
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<access-token token-handler="App\Security\AccessTokenHandler"/>
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</firewall>
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</config>
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</srv:container>
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.. code-block:: php
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// src/Security/AccessTokenHandler.php
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namespace App\Security;
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// config/packages/security.php
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use App\Security\AccessTokenHandler;
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use Symfony\Config\SecurityConfig;
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use App\Repository\AccessTokenRepository;
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use Symfony\Component\Security\Http\AccessToken\AccessTokenHandlerInterface;
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return static function (SecurityConfig $security) {
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$security->firewall('main')
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->accessToken()
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->tokenHandler(AccessTokenHandler::class)
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;
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};
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class AccessTokenHandler implements AccessTokenHandlerInterface
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{
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public function __construct(
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private readonly AccessTokenRepository $repository
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) {
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}
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This handler must implement
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:class:`Symfony\\Component\\Security\\Http\\AccessToken\\AccessTokenHandlerInterface`::
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// src/Security/AccessTokenHandler.php
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namespace App\Security;
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public function getUserIdentifierFrom(string $token): string
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{
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$accessToken = $this->repository->findOneByValue($token);
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if ($accessToken === null || !$accessToken->isValid()) {
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throw new BadCredentialsException('Invalid credentials.');
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}
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use App\Repository\AccessTokenRepository;
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use Symfony\Component\Security\Http\AccessToken\AccessTokenHandlerInterface;
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return $accessToken->getUserId();
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class AccessTokenHandler implements AccessTokenHandlerInterface
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{
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public function __construct(
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private AccessTokenRepository $repository
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) {
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}
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public function getUserIdentifierFrom(string $token): string
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{
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// e.g. query the "access token" database to search for this token
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$accessToken = $this->repository->findOneByValue($token);
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if ($accessToken === null || !$accessToken->isValid()) {
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throw new BadCredentialsException('Invalid credentials.');
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}
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// and return the user identifier from the found token
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return $accessToken->getUserId();
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}
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}
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The access token authenticator will use the returned user identifier to
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load the user using the :ref:`user provider <security-user-providers>`.
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.. caution::
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It is important to check the token is valid.
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For instance, in the example we verify the token has not expired.
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With self-contained access tokens such as JWT, the handler is required to
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verify the digital signature and understand all claims,
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especially ``sub``, ``iat``, ``nbf`` and ``exp``.
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It is important to check the token if is valid. For instance, the
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example above verifies whether the token has not expired. With
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self-contained access tokens such as JWT, the handler is required to
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verify the digital signature and understand all claims, especially
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``sub``, ``iat``, ``nbf`` and ``exp``.
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Customizing the Authenticator
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-----------------------------
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2) Configure the Token Extractor (Optional)
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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1) Access Token Extractors
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The application is now ready to handle incoming tokens. A *token extractor*
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retrieves the token from the request (e.g. a header or request body).
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By default, the access token is read from the request header parameter ``Authorization`` with the scheme ``Bearer``.
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You can change the behavior and send the access token through different ways.
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By default, the access token is read from the request header parameter
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``Authorization`` with the scheme ``Bearer`` (e.g. ``Authorization: Bearer
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the-token-value``).
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This authenticator provides services able to extract the access token as per the RFC6750:
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Symfony provides other extractors as per the `RFC6750`_:
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- ``header`` or ``security.access_token_extractor.header``: the token is sent through the request header. Usually ``Authorization`` with the ``Bearer`` scheme.
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- ``query_string`` or ``security.access_token_extractor.query_string``: the token is part of the query string. Usually ``access_token``.
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- ``request_body`` or ``security.access_token_extractor.request_body``: the token is part of the request body during a POST request. Usually ``access_token``.
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``header`` (default)
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The token is sent through the request header. Usually ``Authorization``
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with the ``Bearer`` scheme.
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``query_string``
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The token is part of the request query string. Usually ``access_token``.
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``request_body``
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The token is part of the request body during a POST request. Usually
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``access_token``.
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.. caution::
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Because of the security weaknesses associated with the URI method,
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including the high likelihood that the URL or the request body containing the access token will be logged,
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methods ``query_string`` and ``request_body`` **SHOULD NOT** be used unless it is impossible
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to transport the access token in the request header field.
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including the high likelihood that the URL or the request body
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containing the access token will be logged, methods ``query_string``
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and ``request_body`` **SHOULD NOT** be used unless it is impossible to
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transport the access token in the request header field.
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Also, you can also create a custom extractor. The class shall implement the interface
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You can also create a custom extractor. The class must implement
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:class:`Symfony\\Component\\Security\\Http\\AccessToken\\AccessTokenExtractorInterface`.
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.. configuration-block::
@@ -112,10 +156,60 @@ Also, you can also create a custom extractor. The class shall implement the inte
112156
main:
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access_token:
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token_handler: App\Security\AccessTokenHandler
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token_extractors: 'my_custom_access_token_extractor'
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It is possible to set multiple extractors.
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In this case, **the order is important**: the first in the list is called first.
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# use a different built-in extractor
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token_extractors: request_body
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# or provide the service ID of a custom extractor
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token_extractors: 'App\Security\CustomTokenExtractor'
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.. code-block:: xml
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<!-- config/packages/security.xml -->
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<?xml version="1.0" encoding="UTF-8"?>
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<srv:container xmlns="http://symfony.com/schema/dic/security"
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xmlns:srv="http://symfony.com/schema/dic/services"
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xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
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xsi:schemaLocation="http://symfony.com/schema/dic/services
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https://symfony.com/schema/dic/services/services-1.0.xsd
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http://symfony.com/schema/dic/security
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https://symfony.com/schema/dic/security/security-1.0.xsd">
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<config>
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<firewall name="main">
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<access-token token-handler="App\Security\AccessTokenHandler">
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<!-- use a different built-in extractor -->
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<token-extractor>request_body</token-extractor>
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<!-- or provide the service ID of a custom extractor -->
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<token-extractor>App\Security\CustomTokenExtractor</token-extractor>
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</access-token>
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</firewall>
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</config>
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</srv:container>
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.. code-block:: php
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// config/packages/security.php
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use App\Security\AccessTokenHandler;
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use App\Security\CustomTokenExtractor;
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use Symfony\Config\SecurityConfig;
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return static function (SecurityConfig $security) {
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$security->firewall('main')
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->accessToken()
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->tokenHandler(AccessTokenHandler::class)
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// use a different built-in extractor
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->tokenExtractors('request_body')
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# or provide the service ID of a custom extractor
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->tokenExtractors(CustomTokenExtractor::class)
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;
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};
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It is possible to set multiple extractors. In this case, **the order is
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important**: the first in the list is called first.
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.. configuration-block::
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@@ -129,37 +223,70 @@ In this case, **the order is important**: the first in the list is called first.
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token_handler: App\Security\AccessTokenHandler
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token_extractors:
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- 'header'
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- 'request_body'
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- 'query_string'
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- 'my_custom_access_token_extractor'
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- 'App\Security\CustomTokenExtractor'
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.. code-block:: xml
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<!-- config/packages/security.xml -->
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<?xml version="1.0" encoding="UTF-8"?>
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<srv:container xmlns="http://symfony.com/schema/dic/security"
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xmlns:srv="http://symfony.com/schema/dic/services"
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xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
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xsi:schemaLocation="http://symfony.com/schema/dic/services
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https://symfony.com/schema/dic/services/services-1.0.xsd
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http://symfony.com/schema/dic/security
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https://symfony.com/schema/dic/security/security-1.0.xsd">
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<config>
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<firewall name="main">
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<access-token token-handler="App\Security\AccessTokenHandler">
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<token-extractor>header</token-extractor>
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<token-extractor>App\Security\CustomTokenExtractor</token-extractor>
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</access-token>
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</firewall>
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</config>
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</srv:container>
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2) Customizing the Success Handler
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.. code-block:: php
137251
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Sometimes, the default success handling does not fit your use-case (e.g.
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when you need to generate and return additional response header parameters).
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To customize how the success handler behaves, create your own handler as a class that implements
141-
:class:`Symfony\\Component\\Security\\Http\\Authentication\\AuthenticationSuccessHandlerInterface`::
252+
// config/packages/security.php
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use App\Security\AccessTokenHandler;
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use App\Security\CustomTokenExtractor;
255+
use Symfony\Config\SecurityConfig;
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143-
// src/Security/Authentication/AuthenticationSuccessHandler.php
144-
namespace App\Security\Authentication;
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return static function (SecurityConfig $security) {
258+
$security->firewall('main')
259+
->accessToken()
260+
->tokenHandler(AccessTokenHandler::class)
261+
->tokenExtractors([
262+
'header',
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CustomTokenExtractor::class,
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])
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;
266+
};
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use Symfony\Component\HttpFoundation\JsonResponse;
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use Symfony\Component\HttpFoundation\Request;
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use Symfony\Component\Security\Core\Authentication\Token\TokenInterface;
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use Symfony\Component\Security\Http\Authentication\AuthenticationSuccessHandlerInterface;
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3) Submit a Request
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~~~~~~~~~~~~~~~~~~~
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class AuthenticationSuccessHandler implements AuthenticationSuccessHandlerInterface
152-
{
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public function onAuthenticationSuccess(Request $request, TokenInterface $token): JsonResponse
154-
{
155-
$user = $token->getUser();
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$userApiToken = $user->getApiToken();
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That's it! Your application can now authenticate incoming requests using an
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API token.
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return new JsonResponse(['apiToken' => $userApiToken]);
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}
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}
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Using the default header extractor, you can test the feature by submitting
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a request like this:
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Then, configure this service ID as the ``success_handler``:
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.. code-block:: terminal
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279+
$ curl -H 'Authorization: Bearer an-accepted-token-value' \
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https://localhost:8000/api/some-route
281+
282+
Customizing the Success Handler
283+
-------------------------------
284+
285+
By default, the request continues (e.g. the controller for the route is
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run). If you want to customize success handling, create your own success
287+
handler by creating a class that implements
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:class:`Symfony\\Component\\Security\\Http\\Authentication\\AuthenticationSuccessHandlerInterface`
289+
and configure the service ID as the ``success_handler``:
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.. configuration-block::
165292

@@ -173,10 +300,48 @@ Then, configure this service ID as the ``success_handler``:
173300
token_handler: App\Security\AccessTokenHandler
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success_handler: App\Security\Authentication\AuthenticationSuccessHandler
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.. code-block:: xml
304+
305+
<!-- config/packages/security.xml -->
306+
<?xml version="1.0" encoding="UTF-8"?>
307+
<srv:container xmlns="http://symfony.com/schema/dic/security"
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xmlns:srv="http://symfony.com/schema/dic/services"
309+
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
310+
xsi:schemaLocation="http://symfony.com/schema/dic/services
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https://symfony.com/schema/dic/services/services-1.0.xsd
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http://symfony.com/schema/dic/security
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https://symfony.com/schema/dic/security/security-1.0.xsd">
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<config>
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<firewall name="main">
317+
<access-token token-handler="App\Security\AccessTokenHandler"
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success-handler="App\Security\Authentication\AuthenticationSuccessHandler"
319+
/>
320+
</firewall>
321+
</config>
322+
</srv:container>
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324+
.. code-block:: php
325+
326+
// config/packages/security.php
327+
use App\Security\AccessTokenHandler;
328+
use App\Security\Authentication\AuthenticationSuccessHandler;
329+
use Symfony\Config\SecurityConfig;
330+
331+
return static function (SecurityConfig $security) {
332+
$security->firewall('main')
333+
->accessToken()
334+
->tokenHandler(AccessTokenHandler::class)
335+
->successHandler(AuthenticationSuccessHandler::class)
336+
;
337+
};
338+
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.. tip::
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178341
If you want to customize the default failure handling, use the
179342
``failure_handler`` option and create a class that implements
180343
:class:`Symfony\\Component\\Security\\Http\\Authentication\\AuthenticationFailureHandlerInterface`.
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.. _`Json Web Tokens (JWT)`: https://datatracker.ietf.org/doc/html/rfc7519
346+
.. _`SAML2 (XML structures)`: https://docs.oasis-open.org/security/saml/Post2.0/sstc-saml-tech-overview-2.0.html
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.. _`RFC6750`: https://datatracker.ietf.org/doc/html/rfc6750

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