title: Access Symfony session values from external application
body: <p>I have a third party application (<code>responsivefilemanager</code> plugin for <code>TinyMCE</code>) that I can't re-write it using <code>Symfony2</code>.<br>
  I need to protect it against unauthorized users.<br>
  Is it possible to access <code>Symfony2</code>'s session variables (user, roles , etc) from external application?  <strong>How?</strong><br>
  I tried to do <code>session_start()</code> and read <code>$_SESSION</code> variable, but it is empty!<br>
  My <code>config.yml</code> is:  </p>
  
  <pre><code>imports:
      - { resource: parameters.yml }
      - { resource: security.yml }
      - { resource: @ar1y4nArticleBundle/Resources/config/admin.yml }
  
  framework:
      #esi:             ~
      translator:      { fallback: %locale% }
      secret:          %secret%
      router:
          resource: "%kernel.root_dir%/config/routing.yml"
          strict_requirements: ~
      form:            ~
      csrf_protection: ~
      validation:      { enable_annotations: true }
      templating:
          engines: ['twig']
          #assets_version: SomeVersionScheme
      default_locale:  "%locale%"
      trusted_proxies: ~
      session:         ~
      fragments:       ~
  
  # Twig Configuration
  twig:
      debug:            %kernel.debug%
      strict_variables: %kernel.debug%
  
  # Assetic Configuration
  assetic:
      debug:          %kernel.debug%
      use_controller: false
      bundles:        [ ]
      #java: /usr/bin/java
      filters:
          cssrewrite: ~
          #closure:
          #    jar: %kernel.root_dir%/Resources/java/compiler.jar
          #yui_css:
          #    jar: %kernel.root_dir%/Resources/java/yuicompressor-2.4.7.jar
  
  # Doctrine Configuration
  doctrine:
      dbal:
          driver:   %database_driver%
          host:     %database_host%
          port:     %database_port%
          dbname:   %database_name%
          user:     %database_user%
          password: %database_password%
          charset:  UTF8
          types: #this is about this line and line below
              json:     Sonata\Doctrine\Types\JsonType
          # if using pdo_sqlite as your database driver, add the path in parameters.yml
          # e.g. database_path: %kernel.root_dir%/data/data.db3
          # path:     %database_path%
  
      orm:
          auto_generate_proxy_classes: %kernel.debug%
          auto_mapping: true
  
  # Swiftmailer Configuration
  swiftmailer:
      transport: %mailer_transport%
      host:      %mailer_host%
      username:  %mailer_user%
      password:  %mailer_password%
      spool:     { type: memory }
  
  fos_user:
      db_driver: orm # other valid values are 'mongodb', 'couchdb' and 'propel'
      firewall_name: main
      user_class:     ar1y4n\UserBundle\Entity\User
  
      group:
          group_class: ar1y4n\UserBundle\Entity\Group  
  
  sonata_block:
      default_contexts: [cms]
      blocks:
          sonata.admin.block.admin_list:
              contexts:   [admin]
  
          #sonata.admin_doctrine_orm.block.audit:
          #    contexts:   [admin]
  
          sonata.block.service.text:
          sonata.block.service.rss:
  
          sonata.user.block.menu:    # used to display the menu in profile pages
          sonata.user.block.account: # used to display menu option (login option)
  
          # Some specific block from the SonataMediaBundle
          #sonata.media.block.media:
          #sonata.media.block.gallery:
          #sonata.media.block.feature_media:
  
  knp_menu:
      twig:  # use "twig: false" to disable the Twig extension and the TwigRenderer
          template: knp_menu.html.twig
      templating: false # if true, enables the helper for PHP templates
      default_renderer: twig # The renderer to use, list is also available by default
  
  sonata_user:
      security_acl: true
      class:                  # Entity Classes
          user:               ar1y4n\UserBundle\Entity\User
          group:              ar1y4n\UserBundle\Entity\Group  
  
  sonata_admin:
      title:      My title
      title_logo: bundles/ar1y4narticle/images/logo-big.png
  
  genemu_form:
      tinymce:
          enabled: true
          theme:   modern
          configs: {plugins: ["responsivefilemanager advlist autolink lists link image charmap print preview hr anchor pagebreak","searchreplace wordcount visualblocks visualchars code fullscreen","insertdatetime media nonbreaking save table contextmenu directionality", "emoticons template paste textcolor"],toolbar1: "insertfile undo redo | styleselect | bold italic | alignleft aligncenter alignright alignjustify | bullist numlist outdent indent | link image",toolbar2: "print preview media | forecolor backcolor emoticons | responsivefilemanager",image_advtab: true, external_filemanager_path:"/filemanager/",filemanager_title:"Responsive Filemanager" ,external_plugins: { "filemanager" : "/filemanager/plugin.min.js"}}                 
  </code></pre>