--- /dev/null
+<?php
+
+namespace Drupal\Core\Session;
+
+use Symfony\Component\HttpFoundation\Request;
+
+/**
+ * Defines an interface for session configuration generators.
+ */
+interface SessionConfigurationInterface {
+
+ /**
+ * Determines whether a session identifier is on the request.
+ *
+ * This method detects whether a session was started during one of the
+ * previous requests from the same user agent. Session identifiers are
+ * normally passed along using cookies and hence a typical implementation
+ * checks whether the session cookie is on the request.
+ *
+ * @param \Symfony\Component\HttpFoundation\Request $request
+ * The request.
+ *
+ * @return bool
+ * TRUE if there is a session identifier on the request.
+ */
+ public function hasSession(Request $request);
+
+ /**
+ * Returns a list of options suitable for passing to the session storage.
+ *
+ * @see \Symfony\Component\HttpFoundation\Session\Storage\NativeSessionStorage::__construct()
+ *
+ * @param \Symfony\Component\HttpFoundation\Request $request
+ * The request.
+ *
+ * @return array
+ * An associative array of session ini settings.
+ */
+ public function getOptions(Request $request);
+
+}