12 files changed, 370 insertions, 15 deletions
diff --git a/Swiften/Roster/GetRosterRequest.h b/Swiften/Roster/GetRosterRequest.h
index 00cf77f..a3486f0 100644
--- a/Swiften/Roster/GetRosterRequest.h
+++ b/Swiften/Roster/GetRosterRequest.h
@@ -19,6 +19,12 @@ namespace Swift {
 				return ref(new GetRosterRequest(router));
 			}
 
+			static ref create(IQRouter* router, const std::string& version) {
+				ref result(new GetRosterRequest(router));
+				result->getPayloadGeneric()->setVersion(version);
+				return result;
+			}
+
 		private:
 			GetRosterRequest(IQRouter* router) :
 					GenericRequest<RosterPayload>(IQ::Get, JID(), boost::shared_ptr<Payload>(new RosterPayload()), router) {
diff --git a/Swiften/Roster/RosterFileStorage.cpp b/Swiften/Roster/RosterFileStorage.cpp
new file mode 100644
index 0000000..de7b442
--- /dev/null
+++ b/Swiften/Roster/RosterFileStorage.cpp
@@ -0,0 +1,24 @@
+/*
+ * Copyright (c) 2011 Remko Tronçon
+ * Licensed under the GNU General Public License v3.
+ * See Documentation/Licenses/GPLv3.txt for more information.
+ */
+
+#include <Swiften/Roster/RosterFileStorage.h>
+
+#include <boost/smart_ptr/make_shared.hpp>
+
+namespace Swift {
+
+RosterFileStorage::RosterFileStorage(const boost::filesystem::path& path) : path(path) {
+}
+
+// FIXME
+void RosterFileStorage::setRoster(boost::shared_ptr<RosterPayload> r) {
+	roster.reset();
+	if (r) {
+		roster = boost::make_shared<RosterPayload>(*r);
+	}
+}
+
+}
diff --git a/Swiften/Roster/RosterFileStorage.h b/Swiften/Roster/RosterFileStorage.h
new file mode 100644
index 0000000..dc91c27
--- /dev/null
+++ b/Swiften/Roster/RosterFileStorage.h
@@ -0,0 +1,29 @@
+/*
+ * Copyright (c) 2011 Remko Tronçon
+ * Licensed under the GNU General Public License v3.
+ * See Documentation/Licenses/GPLv3.txt for more information.
+ */
+
+#pragma once
+
+#include <boost/filesystem/path.hpp>
+
+#include <Swiften/Roster/RosterStorage.h>
+
+namespace Swift {
+	class RosterFileStorage : public RosterStorage {
+		public:
+			RosterFileStorage(const boost::filesystem::path& path);
+
+			// FIXME
+			virtual boost::shared_ptr<RosterPayload> getRoster() const {
+				return roster;
+			}
+
+			virtual void setRoster(boost::shared_ptr<RosterPayload>);
+
+		private:
+			boost::filesystem::path path;
+			boost::shared_ptr<RosterPayload> roster;
+	};
+}
diff --git a/Swiften/Roster/RosterMemoryStorage.cpp b/Swiften/Roster/RosterMemoryStorage.cpp
new file mode 100644
index 0000000..cbf4563
--- /dev/null
+++ b/Swiften/Roster/RosterMemoryStorage.cpp
@@ -0,0 +1,23 @@
+/*
+ * Copyright (c) 2011 Remko Tronçon
+ * Licensed under the GNU General Public License v3.
+ * See Documentation/Licenses/GPLv3.txt for more information.
+ */
+
+#include <Swiften/Roster/RosterMemoryStorage.h>
+
+#include <boost/smart_ptr/make_shared.hpp>
+
+namespace Swift {
+
+RosterMemoryStorage::RosterMemoryStorage() {
+}
+
+void RosterMemoryStorage::setRoster(boost::shared_ptr<RosterPayload> r) {
+	roster.reset();
+	if (r) {
+		roster = boost::make_shared<RosterPayload>(*r);
+	}
+}
+
+}
diff --git a/Swiften/Roster/RosterMemoryStorage.h b/Swiften/Roster/RosterMemoryStorage.h
new file mode 100644
index 0000000..b659d77
--- /dev/null
+++ b/Swiften/Roster/RosterMemoryStorage.h
@@ -0,0 +1,25 @@
+/*
+ * Copyright (c) 2011 Remko Tronçon
+ * Licensed under the GNU General Public License v3.
+ * See Documentation/Licenses/GPLv3.txt for more information.
+ */
+
+#pragma once
+
+#include <Swiften/Roster/RosterStorage.h>
+
+namespace Swift {
+	class RosterMemoryStorage : public RosterStorage {
+		public:
+			RosterMemoryStorage();
+
+			virtual boost::shared_ptr<RosterPayload> getRoster() const {
+				return roster;
+			}
+
+			virtual void setRoster(boost::shared_ptr<RosterPayload>);
+
+		private:
+			boost::shared_ptr<RosterPayload> roster;
+	};
+}
diff --git a/Swiften/Roster/RosterStorage.cpp b/Swiften/Roster/RosterStorage.cpp
new file mode 100644
index 0000000..6bf58de
--- /dev/null
+++ b/Swiften/Roster/RosterStorage.cpp
@@ -0,0 +1,14 @@
+/*
+ * Copyright (c) 2011 Remko Tronçon
+ * Licensed under the GNU General Public License v3.
+ * See Documentation/Licenses/GPLv3.txt for more information.
+ */
+
+#include <Swiften/Roster/RosterStorage.h>
+
+namespace Swift {
+
+RosterStorage::~RosterStorage() {
+}
+
+}
diff --git a/Swiften/Roster/RosterStorage.h b/Swiften/Roster/RosterStorage.h
new file mode 100644
index 0000000..ba24cb3
--- /dev/null
+++ b/Swiften/Roster/RosterStorage.h
@@ -0,0 +1,21 @@
+/*
+ * Copyright (c) 2011 Remko Tronçon
+ * Licensed under the GNU General Public License v3.
+ * See Documentation/Licenses/GPLv3.txt for more information.
+ */
+
+#pragma once
+
+#include <boost/shared_ptr.hpp>
+
+#include <Swiften/Elements/RosterPayload.h>
+
+namespace Swift {
+	class RosterStorage {
+		public:
+			virtual ~RosterStorage();
+
+			virtual boost::shared_ptr<RosterPayload> getRoster() const = 0;
+			virtual void setRoster(boost::shared_ptr<RosterPayload>) = 0;
+	};
+}
diff --git a/Swiften/Roster/UnitTest/XMPPRosterControllerTest.cpp b/Swiften/Roster/UnitTest/XMPPRosterControllerTest.cpp
index 4ef1cc1..4c98673 100644
--- a/Swiften/Roster/UnitTest/XMPPRosterControllerTest.cpp
+++ b/Swiften/Roster/UnitTest/XMPPRosterControllerTest.cpp
@@ -16,15 +16,24 @@
 #include "Swiften/Client/DummyStanzaChannel.h"
 #include "Swiften/Queries/IQRouter.h"
 #include "Swiften/Roster/XMPPRosterImpl.h"
+#include <Swiften/Roster/RosterMemoryStorage.h>
 
 using namespace Swift;
 
 class XMPPRosterControllerTest : public CppUnit::TestFixture {
 		CPPUNIT_TEST_SUITE(XMPPRosterControllerTest);
+		CPPUNIT_TEST(testGet_Response);
 		CPPUNIT_TEST(testGet_EmptyResponse);
+		CPPUNIT_TEST(testGet_NoRosterInStorage);
+		CPPUNIT_TEST(testGet_NoVersionInStorage);
+		CPPUNIT_TEST(testGet_VersionInStorage);
+		CPPUNIT_TEST(testGet_ServerDoesNotSupportVersion);
+		CPPUNIT_TEST(testGet_ResponseWithoutNewVersion);
+		CPPUNIT_TEST(testGet_ResponseWithNewVersion);
 		CPPUNIT_TEST(testAdd);
 		CPPUNIT_TEST(testModify);
 		CPPUNIT_TEST(testRemove);
+		CPPUNIT_TEST(testRemove_RosterStorageUpdated);
 		CPPUNIT_TEST(testMany);
 		CPPUNIT_TEST_SUITE_END();
 
@@ -34,20 +43,36 @@ class XMPPRosterControllerTest : public CppUnit::TestFixture {
 			router_ = new IQRouter(channel_);
 			xmppRoster_ = new XMPPRosterImpl();
 			handler_ = new XMPPRosterSignalHandler(xmppRoster_);
+			rosterStorage_ = new RosterMemoryStorage();
 			jid1_ = JID("foo@bar.com");
 			jid2_ = JID("alice@wonderland.lit");
 			jid3_ = JID("jane@austen.lit");
 		}
 
 		void tearDown() {
+			delete rosterStorage_;
 			delete handler_;
 			delete xmppRoster_;
 			delete router_;
 			delete channel_;
 		}
 
+		void testGet_Response() {
+			std::auto_ptr<XMPPRosterController> testling(createController());
+
+			testling->requestRoster();
+			boost::shared_ptr<RosterPayload> payload = boost::make_shared<RosterPayload>();
+			payload->addItem(RosterItemPayload(jid1_, "Bob", RosterItemPayload::Both));
+			payload->addItem(RosterItemPayload(jid2_, "Alice", RosterItemPayload::Both));
+			channel_->onIQReceived(IQ::createResult("foo@bar.com", channel_->sentStanzas[0]->getID(), payload));
+
+			CPPUNIT_ASSERT_EQUAL(2, handler_->getEventCount());
+			CPPUNIT_ASSERT(xmppRoster_->getItem(jid1_));
+			CPPUNIT_ASSERT(xmppRoster_->getItem(jid2_));
+		}
+
 		void testGet_EmptyResponse() {
-			XMPPRosterController controller(router_, xmppRoster_);
+			XMPPRosterController controller(router_, xmppRoster_, rosterStorage_);
 
 			controller.requestRoster();
 
@@ -55,7 +80,7 @@ class XMPPRosterControllerTest : public CppUnit::TestFixture {
 		}
 
 		void testAdd() {
-			XMPPRosterController controller(router_, xmppRoster_);
+			XMPPRosterController controller(router_, xmppRoster_, rosterStorage_);
 
 			boost::shared_ptr<RosterPayload> payload(new RosterPayload());
 			payload->addItem(RosterItemPayload(jid1_, "Bob", RosterItemPayload::Both));
@@ -68,8 +93,115 @@ class XMPPRosterControllerTest : public CppUnit::TestFixture {
 			CPPUNIT_ASSERT_EQUAL(std::string("Bob"), xmppRoster_->getNameForJID(jid1_));
 		}
 
+		void testGet_NoRosterInStorage() {
+			std::auto_ptr<XMPPRosterController> testling(createController());
+			testling->setUseVersioning(true);
+
+			testling->requestRoster();
+
+			boost::shared_ptr<RosterPayload> roster = channel_->sentStanzas[0]->getPayload<RosterPayload>();
+			CPPUNIT_ASSERT(roster->getVersion());
+			CPPUNIT_ASSERT_EQUAL(std::string(""), *roster->getVersion());
+		}
+
+		void testGet_NoVersionInStorage() {
+			std::auto_ptr<XMPPRosterController> testling(createController());
+			testling->setUseVersioning(true);
+			rosterStorage_->setRoster(boost::make_shared<RosterPayload>());
+
+			testling->requestRoster();
+
+			boost::shared_ptr<RosterPayload> roster = channel_->sentStanzas[0]->getPayload<RosterPayload>();
+			CPPUNIT_ASSERT(roster->getVersion());
+			CPPUNIT_ASSERT_EQUAL(std::string(""), *roster->getVersion());
+		}
+
+		void testGet_VersionInStorage() {
+			std::auto_ptr<XMPPRosterController> testling(createController());
+			testling->setUseVersioning(true);
+			boost::shared_ptr<RosterPayload> payload(new RosterPayload());
+			payload->setVersion("foover");
+			rosterStorage_->setRoster(payload);
+
+			testling->requestRoster();
+
+			boost::shared_ptr<RosterPayload> roster = channel_->sentStanzas[0]->getPayload<RosterPayload>();
+			CPPUNIT_ASSERT(roster->getVersion());
+			CPPUNIT_ASSERT_EQUAL(std::string("foover"), *roster->getVersion());
+		}
+
+		void testGet_ServerDoesNotSupportVersion() {
+			std::auto_ptr<XMPPRosterController> testling(createController());
+			boost::shared_ptr<RosterPayload> payload(new RosterPayload());
+			payload->setVersion("foover");
+			rosterStorage_->setRoster(payload);
+
+			testling->requestRoster();
+
+			boost::shared_ptr<RosterPayload> roster = channel_->sentStanzas[0]->getPayload<RosterPayload>();
+			CPPUNIT_ASSERT(!roster->getVersion());
+		}
+
+		void testGet_ResponseWithoutNewVersion() {
+			std::auto_ptr<XMPPRosterController> testling(createController());
+			testling->setUseVersioning(true);
+			boost::shared_ptr<RosterPayload> storedRoster(new RosterPayload());
+			storedRoster->setVersion("version10");
+			storedRoster->addItem(RosterItemPayload(jid1_, "Bob", RosterItemPayload::Both));
+			storedRoster->addItem(RosterItemPayload(jid2_, "Alice", RosterItemPayload::Both));
+			rosterStorage_->setRoster(storedRoster);
+			testling->requestRoster();
+
+			channel_->onIQReceived(IQ::createResult("foo@bar.com", channel_->sentStanzas[0]->getID(), boost::shared_ptr<RosterPayload>()));
+
+			CPPUNIT_ASSERT_EQUAL(2, handler_->getEventCount());
+			CPPUNIT_ASSERT(xmppRoster_->getItem(jid1_));
+			CPPUNIT_ASSERT(xmppRoster_->getItem(jid2_));
+			CPPUNIT_ASSERT_EQUAL(Add, handler_->getLastEvent());
+			CPPUNIT_ASSERT_EQUAL(jid2_, handler_->getLastJID());
+			CPPUNIT_ASSERT(rosterStorage_->getRoster());
+			CPPUNIT_ASSERT(rosterStorage_->getRoster()->getVersion());
+			CPPUNIT_ASSERT_EQUAL(std::string("version10"), *rosterStorage_->getRoster()->getVersion());
+			CPPUNIT_ASSERT(rosterStorage_->getRoster()->getItem(jid1_));
+			CPPUNIT_ASSERT(rosterStorage_->getRoster()->getItem(jid2_));
+		}
+
+		void testGet_ResponseWithNewVersion() {
+			std::auto_ptr<XMPPRosterController> testling(createController());
+			testling->setUseVersioning(true);
+			boost::shared_ptr<RosterPayload> storedRoster(new RosterPayload());
+			storedRoster->setVersion("version10");
+			storedRoster->addItem(RosterItemPayload(jid1_, "Bob", RosterItemPayload::Both));
+			rosterStorage_->setRoster(storedRoster);
+			testling->requestRoster();
+
+			boost::shared_ptr<RosterPayload> serverRoster(new RosterPayload());
+			serverRoster->setVersion("version12");
+			serverRoster->addItem(RosterItemPayload(jid2_, "Alice", RosterItemPayload::Both));
+			std::vector<std::string> groups;
+			groups.push_back("foo");
+			groups.push_back("bar");
+			serverRoster->addItem(RosterItemPayload(jid3_, "Rabbit", RosterItemPayload::Both, groups));
+			channel_->onIQReceived(IQ::createResult("foo@bar.com", channel_->sentStanzas[0]->getID(), serverRoster));
+
+
+			CPPUNIT_ASSERT_EQUAL(2, handler_->getEventCount());
+			CPPUNIT_ASSERT(!xmppRoster_->getItem(jid1_));
+			CPPUNIT_ASSERT(xmppRoster_->getItem(jid2_));
+			CPPUNIT_ASSERT(xmppRoster_->getItem(jid3_));
+			CPPUNIT_ASSERT_EQUAL(jid3_, handler_->getLastJID());
+			CPPUNIT_ASSERT_EQUAL(Add, handler_->getLastEvent());
+			CPPUNIT_ASSERT(rosterStorage_->getRoster());
+			CPPUNIT_ASSERT(rosterStorage_->getRoster()->getVersion());
+			CPPUNIT_ASSERT_EQUAL(std::string("version12"), *rosterStorage_->getRoster()->getVersion());
+			CPPUNIT_ASSERT(!rosterStorage_->getRoster()->getItem(jid1_));
+			CPPUNIT_ASSERT(rosterStorage_->getRoster()->getItem(jid2_));
+			CPPUNIT_ASSERT(rosterStorage_->getRoster()->getItem(jid3_));
+			CPPUNIT_ASSERT_EQUAL(2, static_cast<int>(rosterStorage_->getRoster()->getItem(jid3_)->getGroups().size()));
+		}
+
 		void testModify() {
-			XMPPRosterController controller(router_, xmppRoster_);
+			XMPPRosterController controller(router_, xmppRoster_, rosterStorage_);
 			boost::shared_ptr<RosterPayload> payload1(new RosterPayload());
 			payload1->addItem(RosterItemPayload(jid1_, "Bob", RosterItemPayload::Both));
 			channel_->onIQReceived(IQ::createRequest(IQ::Set, JID(), "id1", payload1));
@@ -87,9 +219,9 @@ class XMPPRosterControllerTest : public CppUnit::TestFixture {
 
 			CPPUNIT_ASSERT_EQUAL(std::string("Bob2"), xmppRoster_->getNameForJID(jid1_));
 		}
-
+		
 		void testRemove() {
-			XMPPRosterController controller(router_, xmppRoster_);
+			XMPPRosterController controller(router_, xmppRoster_, rosterStorage_);
 			boost::shared_ptr<RosterPayload> payload1(new RosterPayload());
 			payload1->addItem(RosterItemPayload(jid1_, "Bob", RosterItemPayload::Both));
 			channel_->onIQReceived(IQ::createRequest(IQ::Set, JID(), "id1", payload1));
@@ -107,8 +239,31 @@ class XMPPRosterControllerTest : public CppUnit::TestFixture {
 
 		}
 
+		void testRemove_RosterStorageUpdated() {
+			std::auto_ptr<XMPPRosterController> testling(createController());
+			testling->setUseVersioning(true);
+			boost::shared_ptr<RosterPayload> storedRoster(new RosterPayload());
+			storedRoster->setVersion("version10");
+			storedRoster->addItem(RosterItemPayload(jid1_, "Bob", RosterItemPayload::Both));
+			storedRoster->addItem(RosterItemPayload(jid2_, "Alice", RosterItemPayload::Both));
+			rosterStorage_->setRoster(storedRoster);
+			testling->requestRoster();
+			channel_->onIQReceived(IQ::createResult("foo@bar.com", channel_->sentStanzas[0]->getID(), boost::shared_ptr<RosterPayload>()));
+
+			boost::shared_ptr<RosterPayload> payload2(new RosterPayload());
+			payload2->setVersion("version15");
+			payload2->addItem(RosterItemPayload(jid1_, "Bob", RosterItemPayload::Remove));
+			channel_->onIQReceived(IQ::createRequest(IQ::Set, JID(), "id2", payload2));
+
+			CPPUNIT_ASSERT(rosterStorage_->getRoster());
+			CPPUNIT_ASSERT(rosterStorage_->getRoster()->getVersion());
+			CPPUNIT_ASSERT_EQUAL(std::string("version15"), *rosterStorage_->getRoster()->getVersion());
+			CPPUNIT_ASSERT(!rosterStorage_->getRoster()->getItem(jid1_));
+			CPPUNIT_ASSERT(rosterStorage_->getRoster()->getItem(jid2_));
+		}
+
 		void testMany() {
-			XMPPRosterController controller(router_, xmppRoster_);
+			XMPPRosterController controller(router_, xmppRoster_, rosterStorage_);
 			boost::shared_ptr<RosterPayload> payload1(new RosterPayload());
 			payload1->addItem(RosterItemPayload(jid1_, "Bob", RosterItemPayload::Both));
 			channel_->onIQReceived(IQ::createRequest(IQ::Set, JID(), "id1", payload1));
@@ -171,12 +326,18 @@ class XMPPRosterControllerTest : public CppUnit::TestFixture {
 			handler_->reset();
 
 		}
+	
+	private:
+			XMPPRosterController* createController() {
+				return new XMPPRosterController(router_, xmppRoster_, rosterStorage_);
+			}
 
 	private:
 		DummyStanzaChannel* channel_;
 		IQRouter* router_;
 		XMPPRosterImpl* xmppRoster_;
 		XMPPRosterSignalHandler* handler_;
+		RosterMemoryStorage* rosterStorage_;
 		JID jid1_;
 		JID jid2_;
 		JID jid3_;
diff --git a/Swiften/Roster/UnitTest/XMPPRosterSignalHandler.cpp b/Swiften/Roster/UnitTest/XMPPRosterSignalHandler.cpp
index 983bc22..d89644a 100644
--- a/Swiften/Roster/UnitTest/XMPPRosterSignalHandler.cpp
+++ b/Swiften/Roster/UnitTest/XMPPRosterSignalHandler.cpp
@@ -11,7 +11,7 @@
 
 using namespace Swift;
 
-XMPPRosterSignalHandler::XMPPRosterSignalHandler(Swift::XMPPRoster* roster) {
+XMPPRosterSignalHandler::XMPPRosterSignalHandler(Swift::XMPPRoster* roster) : eventCount(0) {
 	lastEvent_ = None;
 	roster->onJIDAdded.connect(boost::bind(&XMPPRosterSignalHandler::handleJIDAdded, this, _1));
 	roster->onJIDRemoved.connect(boost::bind(&XMPPRosterSignalHandler::handleJIDRemoved, this, _1));
@@ -24,4 +24,5 @@ void XMPPRosterSignalHandler::handleJIDUpdated(const Swift::JID& jid, const std:
 	lastOldName_ = oldName;
 	lastOldGroups_ = oldGroups;
 	lastEvent_ = Update;
+	eventCount++;
 }
diff --git a/Swiften/Roster/UnitTest/XMPPRosterSignalHandler.h b/Swiften/Roster/UnitTest/XMPPRosterSignalHandler.h
index c59b4c6..2cf1159 100644
--- a/Swiften/Roster/UnitTest/XMPPRosterSignalHandler.h
+++ b/Swiften/Roster/UnitTest/XMPPRosterSignalHandler.h
@@ -37,15 +37,21 @@ public:
 		lastEvent_ = None;
 	}
 
+	int getEventCount() const {
+		return eventCount;
+	}
+
 private:
 	void handleJIDAdded(const Swift::JID& jid) {
 		lastJID_ = jid;
 		lastEvent_ = Add;
+		eventCount++;
 	}
 
 	void handleJIDRemoved(const Swift::JID& jid) {
 		lastJID_ = jid;
 		lastEvent_ = Remove;
+		eventCount++;
 	}
 
 	void handleJIDUpdated(const Swift::JID& jid, const std::string& oldName, const std::vector<std::string>& oldGroups);
@@ -54,5 +60,5 @@ private:
 	Swift::JID lastJID_;
 	std::string lastOldName_;
 	std::vector<std::string> lastOldGroups_;
-
+	int eventCount;
 };
diff --git a/Swiften/Roster/XMPPRosterController.cpp b/Swiften/Roster/XMPPRosterController.cpp
index a294d35..baa74ff 100644
--- a/Swiften/Roster/XMPPRosterController.cpp
+++ b/Swiften/Roster/XMPPRosterController.cpp
@@ -13,14 +13,15 @@
 #include "Swiften/Queries/IQRouter.h"
 #include "Swiften/Roster/GetRosterRequest.h"
 #include "Swiften/Roster/XMPPRosterImpl.h"
+#include <Swiften/Roster/RosterStorage.h>
 
 namespace Swift {
 	
 /**
  * The controller does not gain ownership of these parameters.
  */
-XMPPRosterController::XMPPRosterController(IQRouter* iqRouter, XMPPRosterImpl* xmppRoster) : iqRouter_(iqRouter), rosterPushResponder_(iqRouter), xmppRoster_(xmppRoster) {
-	rosterPushResponder_.onRosterReceived.connect(boost::bind(&XMPPRosterController::handleRosterReceived, this, _1, false));
+XMPPRosterController::XMPPRosterController(IQRouter* iqRouter, XMPPRosterImpl* xmppRoster, RosterStorage* rosterStorage) : iqRouter_(iqRouter), rosterPushResponder_(iqRouter), xmppRoster_(xmppRoster), rosterStorage_(rosterStorage), useVersioning(false) {
+	rosterPushResponder_.onRosterReceived.connect(boost::bind(&XMPPRosterController::handleRosterReceived, this, _1, false, boost::shared_ptr<RosterPayload>()));
 	rosterPushResponder_.start();
 }
 
@@ -30,12 +31,24 @@ XMPPRosterController::~XMPPRosterController() {
 
 void XMPPRosterController::requestRoster() {
 	xmppRoster_->clear();
-	GetRosterRequest::ref rosterRequest = GetRosterRequest::create(iqRouter_);
-	rosterRequest->onResponse.connect(boost::bind(&XMPPRosterController::handleRosterReceived, this, _1, true));
+
+	boost::shared_ptr<RosterPayload> storedRoster = rosterStorage_->getRoster();
+	GetRosterRequest::ref rosterRequest;
+	if (useVersioning) {
+		std::string version = "";
+		if (storedRoster && storedRoster->getVersion()) {
+			version = *storedRoster->getVersion();
+		}
+		rosterRequest = GetRosterRequest::create(iqRouter_, version);
+	}
+	else {
+		rosterRequest = GetRosterRequest::create(iqRouter_);
+	}
+	rosterRequest->onResponse.connect(boost::bind(&XMPPRosterController::handleRosterReceived, this, _1, true, storedRoster));
 	rosterRequest->send();
 }
 
-void XMPPRosterController::handleRosterReceived(boost::shared_ptr<RosterPayload> rosterPayload, bool initial) {
+void XMPPRosterController::handleRosterReceived(boost::shared_ptr<RosterPayload> rosterPayload, bool initial, boost::shared_ptr<RosterPayload> previousRoster) {
 	if (rosterPayload) {
 		foreach(const RosterItemPayload& item, rosterPayload->getItems()) {
 			//Don't worry about the updated case, the XMPPRoster sorts that out.
@@ -46,9 +59,33 @@ void XMPPRosterController::handleRosterReceived(boost::shared_ptr<RosterPayload>
 			}
 		}
 	}
+	else if (previousRoster) {
+		// The cached version hasn't changed; emit all items
+		foreach(const RosterItemPayload& item, previousRoster->getItems()) {
+			if (item.getSubscription() != RosterItemPayload::Remove) {
+				xmppRoster_->addContact(item.getJID(), item.getName(), item.getGroups(), item.getSubscription());
+			}
+			else {
+				std::cerr << "ERROR: Stored invalid roster item" << std::endl;
+			}
+		}
+	}
 	if (initial) {
 		xmppRoster_->onInitialRosterPopulated();
 	}
+	if (rosterPayload && rosterPayload->getVersion() && useVersioning) {
+		saveRoster(*rosterPayload->getVersion());
+	}
+}
+
+void XMPPRosterController::saveRoster(const std::string& version) {
+	std::vector<XMPPRosterItem> items = xmppRoster_->getItems();
+	boost::shared_ptr<RosterPayload> roster(new RosterPayload());
+	roster->setVersion(version);
+	foreach(const XMPPRosterItem& item, items) {
+		roster->addItem(RosterItemPayload(item.getJID(), item.getName(), item.getSubscription(), item.getGroups()));
+	}
+	rosterStorage_->setRoster(roster);
 }
 
 }
diff --git a/Swiften/Roster/XMPPRosterController.h b/Swiften/Roster/XMPPRosterController.h
index eeb84f6..9313bb6 100644
--- a/Swiften/Roster/XMPPRosterController.h
+++ b/Swiften/Roster/XMPPRosterController.h
@@ -18,21 +18,29 @@
 namespace Swift {
 	class IQRouter;
 	class XMPPRosterImpl;
+	class RosterStorage;
 
 	class XMPPRosterController {
 		public:
-			XMPPRosterController(IQRouter *iqRouter, XMPPRosterImpl* xmppRoster);
+			XMPPRosterController(IQRouter *iqRouter, XMPPRosterImpl* xmppRoster, RosterStorage* storage);
 			~XMPPRosterController();
 
 			void requestRoster();
 
+			void setUseVersioning(bool b) {
+				useVersioning = b;
+			}
+
 		private:
-			void handleRosterReceived(boost::shared_ptr<RosterPayload> rosterPayload, bool initial);
+			void handleRosterReceived(boost::shared_ptr<RosterPayload> rosterPayload, bool initial, boost::shared_ptr<RosterPayload> previousRoster);
+			void saveRoster(const std::string& version);
 
 		private:
 			IQRouter* iqRouter_;
 			RosterPushResponder rosterPushResponder_;
 			XMPPRosterImpl* xmppRoster_;
+			RosterStorage* rosterStorage_;
+			bool useVersioning;
 	};
 }