craue
diff --git a/‎book/controller.rst
Lines changed: 10 additions & 14 deletions b/‎book/controller.rst
Lines changed: 10 additions & 14 deletions
diff --git a/‎book/templating.rst
Lines changed: 1 addition & 35 deletions b/‎book/templating.rst
Lines changed: 1 addition & 35 deletions
diff --git a/‎components/http_foundation/sessions.rst
Lines changed: 0 additions & 13 deletions b/‎components/http_foundation/sessions.rst
Lines changed: 0 additions & 13 deletions
diff --git a/‎cookbook/cache/varnish.rst
Lines changed: 86 additions & 3 deletions b/‎cookbook/cache/varnish.rst
Lines changed: 86 additions & 3 deletions
diff --git a/‎quick_tour/the_controller.rst
Lines changed: 3 additions & 5 deletions b/‎quick_tour/the_controller.rst
Lines changed: 3 additions & 5 deletions
@@ -686,23 +686,19 @@ the ``notice`` message:
 
     .. code-block:: html+jinja
 
-        {% if app.session.started %}
-            {% for flashMessage in app.session.flashbag.get('notice') %}
-                <div class="flash-notice">
-                    {{ flashMessage }}
-                </div>
-            {% endfor %}
-        {% endif %}
+        {% for flashMessage in app.session.flashbag.get('notice') %}
+            <div class="flash-notice">
+                {{ flashMessage }}
+            </div>
+        {% endfor %}
 
     .. code-block:: html+php
 
-        <?php if ($view['session']->isStarted()): ?>
-            <?php foreach ($view['session']->getFlashBag()->get('notice') as $message): ?>
-                <div class="flash-notice">
-                    <?php echo "<div class='flash-error'>$message</div>" ?>
-                </div>
-            <?php endforeach; ?>
-        <?php endif; ?>
+        <?php foreach ($view['session']->getFlashBag()->get('notice') as $message): ?>
+            <div class="flash-notice">
+                <?php echo "<div class='flash-error'>$message</div>" ?>
+            </div>
+        <?php endforeach; ?>
 
 By design, flash messages are meant to live for exactly one request (they're
 "gone in a flash"). They're designed to be used across redirects exactly as
 
@@ -1340,43 +1340,9 @@ in a JavaScript string, use the ``js`` context:
 Debugging
 ---------
 
-.. versionadded:: 2.0.9
-    This feature is available as of Twig ``1.5.x``, which was first shipped
-    with Symfony 2.0.9.
-
 When using PHP, you can use ``var_dump()`` if you need to quickly find the
 value of a variable passed. This is useful, for example, inside your controller.
-The same can be achieved when using Twig by using the debug extension. This
-needs to be enabled in the config:
-
-.. configuration-block::
-
-    .. code-block:: yaml
-
-        # app/config/config.yml
-        services:
-            acme_hello.twig.extension.debug:
-                class:        Twig_Extension_Debug
-                tags:
-                     - { name: 'twig.extension' }
-
-    .. code-block:: xml
-
-        <!-- app/config/config.xml -->
-        <services>
-            <service id="acme_hello.twig.extension.debug" class="Twig_Extension_Debug">
-                <tag name="twig.extension" />
-            </service>
-        </services>
-
-    .. code-block:: php
-
-        // app/config/config.php
-        use Symfony\Component\DependencyInjection\Definition;
-
-        $definition = new Definition('Twig_Extension_Debug');
-        $definition->addTag('twig.extension');
-        $container->setDefinition('acme_hello.twig.extension.debug', $definition);
+The same can be achieved when using Twig thanks to the the debug extension.
 
 Template parameters can then be dumped using the ``dump`` function:
 
 
@@ -333,16 +333,3 @@ Compact method to process display all flashes at once::
             echo "<div class='flash-$type'>$message</div>\n";
         }
     }
-
-.. caution::
-
-    As flash messages use a session to store the messages from one request to
-    the next one, a session will be automatically started when you read the
-    flash messages even if none already exists. To avoid that default
-    behavior, test if there is an existing session first::
-
-        if ($session->isStarted()) {
-            foreach ($session->getFlashBag()->get('warning', array()) as $message) {
-                echo "<div class='flash-warning'>$message</div>";
-            }
-        }
@@ -35,6 +35,7 @@ application:
 .. code-block:: text
 
     sub vcl_recv {
+        // Add a Surrogate-Capability header to announce ESI support.
         set req.http.Surrogate-Capability = "abc=ESI/1.0";
     }
 
@@ -45,12 +46,16 @@ Symfony2 adds automatically:
 .. code-block:: text
 
     sub vcl_fetch {
+        /* 
+        Check for ESI acknowledgement 
+        and remove Surrogate-Control header
+        */
         if (beresp.http.Surrogate-Control ~ "ESI/1.0") {
             unset beresp.http.Surrogate-Control;
 
-            // for Varnish >= 3.0
+            // For Varnish >= 3.0
             set beresp.do_esi = true;
-            // for Varnish < 3.0
+            // For Varnish < 3.0
             // esi;
         }
     }
@@ -75,14 +80,43 @@ that will invalidate the cache for a given resource:
 
 .. code-block:: text
 
+    /* 
+     Connect to the backend server 
+     on the local machine on port 8080
+     */
+    backend default {
+        .host = "127.0.0.1";
+        .port = "8080";
+    }
+
+    sub vcl_recv {
+        /* 
+        Varnish default behaviour doesn't support PURGE.
+        Match the PURGE request and immediately do a cache lookup, 
+        otherwise Varnish will directly pipe the request to the backend
+        and bypass the cache        
+        */
+        if (req.request == "PURGE") {
+            return(lookup);
+        }
+    }
+
     sub vcl_hit {
+        // Match PURGE request
         if (req.request == "PURGE") {
+            // Force object expiration for Varnish < 3.0
             set obj.ttl = 0s;
+            // Do an actual purge for Varnish >= 3.0
+            // purge;
             error 200 "Purged";
         }
     }
 
     sub vcl_miss {
+        /*
+        Match the PURGE request and
+        indicate the request wasn't stored in cache.
+        */
         if (req.request == "PURGE") {
             error 404 "Not purged";
         }
@@ -91,7 +125,56 @@ that will invalidate the cache for a given resource:
 .. caution::
 
     You must protect the ``PURGE`` HTTP method somehow to avoid random people
-    purging your cached data.
+    purging your cached data. You can do this by setting up an access list: 
+
+.. code-block:: text
+    /* 
+     Connect to the backend server 
+     on the local machine on port 8080
+     */
+    backend default {
+        .host = "127.0.0.1";
+        .port = "8080";
+    }
+
+	// Acl's can contain IP's, subnets and hostnames
+    acl purge {
+        "localhost";
+        "192.168.55.0"/24;
+    }
+
+    sub vcl_recv {
+        // Match PURGE request to avoid cache bypassing
+        if (req.request == "PURGE") {
+            // Match client IP to the acl
+            if (!client.ip ~ purge) {
+                // Deny access
+                error 405 "Not allowed.";
+            }
+            // Perform a cache lookup
+            return(lookup);
+        }
+    }
+	
+    sub vcl_hit {
+        // Match PURGE request
+        if (req.request == "PURGE") {
+            // Force object expiration for Varnish < 3.0
+            set obj.ttl = 0s;
+            // Do an actual purge for Varnish >= 3.0
+            // purge;
+            error 200 "Purged";
+        }
+    }	
+
+    sub vcl_miss {
+        // Match PURGE request    
+        if (req.request == "PURGE") {
+            // Indicate that the object isn't stored in cache
+            error 404 "Not purged";
+        }
+    }	
+
 
 .. _`Edge Architecture`: http://www.w3.org/TR/edge-arch
 .. _`GZIP and Varnish`: https://www.varnish-cache.org/docs/3.0/phk/gzip.html
@@ -141,11 +141,9 @@ next request::
 
     // display any messages back in the next request (in a template)
 
-    {% if app.session.started %}
-        {% for flashMessage in app.session.flashbag.get('notice') %}
-            <div>{{ flashMessage }}</div>
-        {% endfor %}
-    {% endif %}
+    {% for flashMessage in app.session.flashbag.get('notice') %}
+        <div>{{ flashMessage }}</div>
+    {% endfor %}
 
 This is useful when you need to set a success message before redirecting
 the user to another page (which will then show the message). Please note that