feature #11668 [HttpFoundation] MongoDbSessionHandler supports auto e…

…xpiry via configurable expiry_field (catchamonkey)

This PR was merged into the 2.6-dev branch.

Discussion
----------

[HttpFoundation] MongoDbSessionHandler supports auto expiry via configurable expiry_field

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #11508
| License       | MIT
| Doc PR        | no

This PR applies #11510 to master instead of 2.3

Should be merged on master:
- [x] after #11667 is merged to 2.3
- [x] and after 2.3 is merged back to master

Commits
-------

beca900 [HttpFoundation] MongoDbSessionHandler supports auto expiry via configurable expiry_field

src/Symfony/Component/HttpFoundation/Session/Storage/Handler/MongoDbSessionHandler.php

@@ -62,9 +62,10 @@ public function __construct($mongo, array $options)
         $this->mongo = $mongo;
 
         $this->options = array_merge(array(
-            'id_field'   => '_id',
-            'data_field' => 'data',
-            'time_field' => 'time',
+            'id_field'     => '_id',
+            'data_field'   => 'data',
+            'time_field'   => 'time',
+            'expiry_field' => false,
         ), $options);
     }
 
@@ -109,6 +110,9 @@ public function gc($maxlifetime)
          *
          * See: http://docs.mongodb.org/manual/tutorial/expire-data/
          */
+        if (false !== $this->options['expiry_field']) {
+            return true;
+        }
         $time = new \MongoDate(time() - $maxlifetime);
 
         $this->getCollection()->remove(array(
@@ -123,12 +127,27 @@ public function gc($maxlifetime)
      */
     public function write($sessionId, $data)
     {
+        $fields = array(
+            $this->options['data_field'] => new \MongoBinData($data, \MongoBinData::BYTE_ARRAY),
+            $this->options['time_field'] => new \MongoDate(),
+        );
+
+        /* Note: As discussed in the gc method of this class. You can utilise
+         * TTL collections in MongoDB 2.2+
+         * We are setting the "expiry_field" as part of the write operation here
+         * You will need to create the index on your collection that expires documents
+         * at that time
+         * e.g.
+         * db.MySessionCollection.ensureIndex( { "expireAt": 1 }, { expireAfterSeconds: 0 } )
+         */
+        if (false !== $this->options['expiry_field']) {
+            $expiry = new \MongoDate(time() + (int) ini_get('session.gc_maxlifetime'));
+            $fields[$this->options['expiry_field']] = $expiry;
+        }
+
         $this->getCollection()->update(
             array($this->options['id_field'] => $sessionId),
-            array('$set' => array(
-                $this->options['data_field'] => new \MongoBinData($data, \MongoBinData::BYTE_ARRAY),
-                $this->options['time_field'] => new \MongoDate(),
-            )),
+            array('$set' => $fields),
             array('upsert' => true, 'multiple' => false)
         );
 

src/Symfony/Component/HttpFoundation/Tests/Session/Storage/Handler/MongoDbSessionHandlerTest.php

@@ -41,7 +41,7 @@ protected function setUp()
             'data_field' => 'data',
             'time_field' => 'time',
             'database' => 'sf2-test',
-            'collection' => 'session-test'
+            'collection' => 'session-test',
         );
 
         $this->storage = new MongoDbSessionHandler($this->mongo, $this->options);
@@ -100,6 +100,45 @@ public function testWrite()
         $that->assertInstanceOf('MongoDate', $data[$this->options['time_field']]);
     }
 
+    public function testWriteWhenUsingExpiresField()
+    {
+        $this->options = array(
+            'id_field'   => '_id',
+            'data_field' => 'data',
+            'time_field' => 'time',
+            'database' => 'sf2-test',
+            'collection' => 'session-test',
+            'expiry_field' => 'expiresAt'
+        );
+
+        $this->storage = new MongoDbSessionHandler($this->mongo, $this->options);
+
+        $collection = $this->createMongoCollectionMock();
+
+        $this->mongo->expects($this->once())
+            ->method('selectCollection')
+            ->with($this->options['database'], $this->options['collection'])
+            ->will($this->returnValue($collection));
+
+        $that = $this;
+        $data = array();
+
+        $collection->expects($this->once())
+            ->method('update')
+            ->will($this->returnCallback(function ($criteria, $updateData, $options) use ($that, &$data) {
+                $that->assertEquals(array($that->options['id_field'] => 'foo'), $criteria);
+                $that->assertEquals(array('upsert' => true, 'multiple' => false), $options);
+
+                $data = $updateData['$set'];
+            }));
+
+        $this->assertTrue($this->storage->write('foo', 'bar'));
+
+        $this->assertEquals('bar', $data[$this->options['data_field']]->bin);
+        $that->assertInstanceOf('MongoDate', $data[$this->options['time_field']]);
+        $that->assertInstanceOf('MongoDate', $data[$this->options['expiry_field']]);
+    }
+
     public function testReplaceSessionData()
     {
         $collection = $this->createMongoCollectionMock();
@@ -154,10 +193,36 @@ public function testGc()
             ->method('remove')
             ->will($this->returnCallback(function ($criteria) use ($that) {
                 $that->assertInstanceOf('MongoDate', $criteria[$that->options['time_field']]['$lt']);
-                $that->assertGreaterThanOrEqual(time() - -1, $criteria[$that->options['time_field']]['$lt']->sec);
+                $that->assertGreaterThanOrEqual(time() - 1, $criteria[$that->options['time_field']]['$lt']->sec);
             }));
 
-        $this->assertTrue($this->storage->gc(-1));
+        $this->assertTrue($this->storage->gc(1));
+    }
+
+    public function testGcWhenUsingExpiresField()
+    {
+        $this->options = array(
+            'id_field'   => '_id',
+            'data_field' => 'data',
+            'time_field' => 'time',
+            'database' => 'sf2-test',
+            'collection' => 'session-test',
+            'expiry_field' => 'expiresAt'
+        );
+
+        $this->storage = new MongoDbSessionHandler($this->mongo, $this->options);
+
+        $collection = $this->createMongoCollectionMock();
+
+        $this->mongo->expects($this->never())
+            ->method('selectCollection');
+
+        $that = $this;
+
+        $collection->expects($this->never())
+            ->method('remove');
+
+        $this->assertTrue($this->storage->gc(1));
     }
 
     public function testGetConnection()