Made disabling of session writes really disable the writes (#728)

- Now no attempt is made to store the session when disabled.

module/VuFind/src/VuFind/Session/AbstractBase.php

@@ -58,6 +58,24 @@ abstract class AbstractBase implements SaveHandlerInterface,
      */
     protected $config = null;
 
+    /**
+     * Whether writes are disabled, i.e. any changes to the session are not written
+     * to the storage
+     *
+     * @var bool
+     */
+    protected $writesDisabled = false;
+
+    /**
+     * Disable session writing, i.e. make it read-only
+     *
+     * @return void
+     */
+    public function disableWrites()
+    {
+        $this->writesDisabled = true;
+    }
+
     /**
      * Set configuration.
      *
@@ -145,4 +163,30 @@ abstract class AbstractBase implements SaveHandlerInterface,
         // Something to keep in mind though.
         return true;
     }
+
+    /**
+     * Write function that is called when session data is to be saved.
+     *
+     * @param string $sess_id The current session ID
+     * @param string $data    The session data to write
+     *
+     * @return bool
+     */
+    public function write($sess_id, $data)
+    {
+        if ($this->writesDisabled) {
+            return true;
+        }
+        return $this->saveSession($sess_id, $data);
+    }
+
+    /**
+     * A function that is called internally when session data is to be saved.
+     *
+     * @param string $sess_id The current session ID
+     * @param string $data    The session data to write
+     *
+     * @return bool
+     */
+    abstract protected function saveSession($sess_id, $data);
 }

module/VuFind/src/VuFind/Session/Database.php

@@ -59,20 +59,6 @@ class Database extends AbstractBase
         }
     }
 
-    /**
-     * Write function that is called when session data is to be saved.
-     *
-     * @param string $sess_id The current session ID
-     * @param string $data    The session data to write
-     *
-     * @return bool
-     */
-    public function write($sess_id, $data)
-    {
-        $this->getTable('Session')->writeSession($sess_id, $data);
-        return true;
-    }
-
     /**
      * The destroy handler, this is executed when a session is destroyed with
      * session_destroy() and takes the session id as its only parameter.
@@ -105,4 +91,18 @@ class Database extends AbstractBase
         $this->getTable('Session')->garbageCollect($sess_maxlifetime);
         return true;
     }
+
+    /**
+     * A function that is called internally when session data is to be saved.
+     *
+     * @param string $sess_id The current session ID
+     * @param string $data    The session data to write
+     *
+     * @return bool
+     */
+    protected function saveSession($sess_id, $data)
+    {
+        $this->getTable('Session')->writeSession($sess_id, $data);
+        return true;
+    }
 }

module/VuFind/src/VuFind/Session/File.php

@@ -100,32 +100,6 @@ class File extends AbstractBase
         return (string)file_get_contents($sess_file);
     }
 
-    /**
-     * Write function that is called when session data is to be saved.
-     *
-     * @param string $sess_id The current session ID
-     * @param string $data    The session data to write
-     *
-     * @return bool
-     */
-    public function write($sess_id, $data)
-    {
-        $sess_file = $this->getPath() . '/sess_' . $sess_id;
-        if ($fp = fopen($sess_file, "w")) {
-            $return = fwrite($fp, $data);
-            fclose($fp);
-            if ($return !== false) {
-                return true;
-            }
-        }
-        // If we got this far, something went wrong with the file output...
-        // It is tempting to throw an exception here, but this code is called
-        // outside of the context of exception handling, so all we can do is
-        // echo a message.
-        echo 'Cannot write session to ' . $sess_file . "\n";
-        return false;
-    }
-
     /**
      * The destroy handler, this is executed when a session is destroyed with
      * session_destroy() and takes the session id as its only parameter.
@@ -164,4 +138,30 @@ class File extends AbstractBase
         }
         return true;
     }
+
+    /**
+     * A function that is called internally when session data is to be saved.
+     *
+     * @param string $sess_id The current session ID
+     * @param string $data    The session data to write
+     *
+     * @return bool
+     */
+    protected function saveSession($sess_id, $data)
+    {
+        $sess_file = $this->getPath() . '/sess_' . $sess_id;
+        if ($fp = fopen($sess_file, "w")) {
+            $return = fwrite($fp, $data);
+            fclose($fp);
+            if ($return !== false) {
+                return true;
+            }
+        }
+        // If we got this far, something went wrong with the file output...
+        // It is tempting to throw an exception here, but this code is called
+        // outside of the context of exception handling, so all we can do is
+        // echo a message.
+        echo 'Cannot write session to ' . $sess_file . "\n";
+        return false;
+    }
 }

module/VuFind/src/VuFind/Session/ManagerFactory.php

@@ -91,7 +91,7 @@ class ManagerFactory implements \Zend\ServiceManager\FactoryInterface
      * handler: http://us.php.net/manual/en/function.session-set-save-handler.php
      *
      * This method sets that up.
-     * 
+     *
      * @param SessionManager $sessionManager Session manager instance
      *
      * @return void
@@ -133,7 +133,7 @@ class ManagerFactory implements \Zend\ServiceManager\FactoryInterface
         // be written as part of the current process):
         $settings = $sm->get('VuFind\Session\Settings');
         if ($settings->setSessionManager($sessionManager)->isWriteDisabled()) {
-            $sessionManager->writeClose();
+            $sessionManager->getSaveHandler()->disableWrites();
         } else {
             // If the session is not disabled, we should set up the normal
             // shutdown function:

module/VuFind/src/VuFind/Session/Memcache.php

@@ -89,21 +89,6 @@ class Memcache extends AbstractBase
         return $this->getConnection()->get("vufind_sessions/{$sess_id}");
     }
 
-    /**
-     * Write function that is called when session data is to be saved.
-     *
-     * @param string $sess_id The current session ID
-     * @param string $data    The session data to write
-     *
-     * @return bool
-     */
-    public function write($sess_id, $data)
-    {
-        return $this->getConnection()->set(
-            "vufind_sessions/{$sess_id}", $data, 0, $this->lifetime
-        );
-    }
-
     /**
      * The destroy handler, this is executed when a session is destroyed with
      * session_destroy() and takes the session id as its only parameter.
@@ -120,4 +105,19 @@ class Memcache extends AbstractBase
         // Perform Memcache-specific cleanup:
         return $this->getConnection()->delete("vufind_sessions/{$sess_id}");
     }
+
+    /**
+     * A function that is called internally when session data is to be saved.
+     *
+     * @param string $sess_id The current session ID
+     * @param string $data    The session data to write
+     *
+     * @return bool
+     */
+    protected function saveSession($sess_id, $data)
+    {
+        return $this->getConnection()->set(
+            "vufind_sessions/{$sess_id}", $data, 0, $this->lifetime
+        );
+    }
 }