Factor out methods for storing and retrieving contact ID.

bramble-api/src/main/java/org/briarproject/bramble/api/client/ClientHelper.java

@@ -1,6 +1,7 @@
 package org.briarproject.bramble.api.client;
 
 import org.briarproject.bramble.api.FormatException;
+import org.briarproject.bramble.api.contact.ContactId;
 import org.briarproject.bramble.api.crypto.PrivateKey;
 import org.briarproject.bramble.api.crypto.PublicKey;
 import org.briarproject.bramble.api.data.BdfDictionary;
@@ -119,4 +120,17 @@ public interface ClientHelper {
 	Map<TransportId, TransportProperties> parseAndValidateTransportPropertiesMap(
 			BdfDictionary properties) throws FormatException;
 
+	/**
+	 * Retrieves the contact ID from the group metadata of the given contact
+	 * group.
+	 */
+	ContactId getContactId(Transaction txn, GroupId contactGroupId)
+		throws DbException, FormatException;
+
+	/**
+	 * Stores the given contact ID in the group metadata of the given contact
+	 * group.
+	 */
+	void setContactId(Transaction txn, GroupId contactGroupId, ContactId c)
+		throws DbException;
 }

bramble-api/src/main/java/org/briarproject/bramble/api/client/ContactGroupConstants.java

@@ -0,0 +1,9 @@
+package org.briarproject.bramble.api.client;
+
+public interface ContactGroupConstants {
+
+	/**
+	 * Group metadata key for associating a contact ID with a contact group.
+	 */
+	String GROUP_KEY_CONTACT_ID = "contactId";
+}

bramble-core/src/main/java/org/briarproject/bramble/client/ClientHelperImpl.java

@@ -2,11 +2,13 @@ package org.briarproject.bramble.client;
 
 import org.briarproject.bramble.api.FormatException;
 import org.briarproject.bramble.api.client.ClientHelper;
+import org.briarproject.bramble.api.contact.ContactId;
 import org.briarproject.bramble.api.crypto.CryptoComponent;
 import org.briarproject.bramble.api.crypto.KeyParser;
 import org.briarproject.bramble.api.crypto.PrivateKey;
 import org.briarproject.bramble.api.crypto.PublicKey;
 import org.briarproject.bramble.api.data.BdfDictionary;
+import org.briarproject.bramble.api.data.BdfEntry;
 import org.briarproject.bramble.api.data.BdfList;
 import org.briarproject.bramble.api.data.BdfReader;
 import org.briarproject.bramble.api.data.BdfReaderFactory;
@@ -39,6 +41,7 @@ import java.util.Map.Entry;
 import javax.annotation.concurrent.Immutable;
 import javax.inject.Inject;
 
+import static org.briarproject.bramble.api.client.ContactGroupConstants.GROUP_KEY_CONTACT_ID;
 import static org.briarproject.bramble.api.identity.Author.FORMAT_VERSION;
 import static org.briarproject.bramble.api.identity.AuthorConstants.MAX_AUTHOR_NAME_LENGTH;
 import static org.briarproject.bramble.api.identity.AuthorConstants.MAX_PUBLIC_KEY_LENGTH;
@@ -389,4 +392,27 @@ class ClientHelperImpl implements ClientHelper {
 		return tpMap;
 	}
 
+	@Override
+	public ContactId getContactId(Transaction txn, GroupId contactGroupId)
+			throws DbException {
+		try {
+			BdfDictionary meta =
+					getGroupMetadataAsDictionary(txn, contactGroupId);
+			return new ContactId(meta.getLong(GROUP_KEY_CONTACT_ID).intValue());
+		} catch (FormatException e) {
+			throw new DbException(e); // Invalid group metadata
+		}
+	}
+
+	@Override
+	public void setContactId(Transaction txn, GroupId contactGroupId,
+			ContactId c) throws DbException {
+		BdfDictionary meta = BdfDictionary.of(
+				new BdfEntry(GROUP_KEY_CONTACT_ID, c.getInt()));
+		try {
+			mergeGroupMetadata(txn, contactGroupId, meta);
+		} catch (FormatException e) {
+			throw new AssertionError(e);
+		}
+	}
 }

bramble-core/src/main/java/org/briarproject/bramble/versioning/ClientVersioningConstants.java

@@ -5,6 +5,5 @@ interface ClientVersioningConstants {
 	// Metadata keys
 	String MSG_KEY_UPDATE_VERSION = "version";
 	String MSG_KEY_LOCAL = "local";
-	String GROUP_KEY_CONTACT_ID = "contactId";
 }
 

bramble-core/src/main/java/org/briarproject/bramble/versioning/ClientVersioningManagerImpl.java

@@ -50,7 +50,6 @@ import static java.util.Collections.emptyList;
 import static org.briarproject.bramble.api.sync.Group.Visibility.INVISIBLE;
 import static org.briarproject.bramble.api.sync.Group.Visibility.SHARED;
 import static org.briarproject.bramble.api.sync.Group.Visibility.VISIBLE;
-import static org.briarproject.bramble.versioning.ClientVersioningConstants.GROUP_KEY_CONTACT_ID;
 import static org.briarproject.bramble.versioning.ClientVersioningConstants.MSG_KEY_LOCAL;
 import static org.briarproject.bramble.versioning.ClientVersioningConstants.MSG_KEY_UPDATE_VERSION;
 
@@ -161,13 +160,7 @@ class ClientVersioningManagerImpl implements ClientVersioningManager,
 		db.addGroup(txn, g);
 		db.setGroupVisibility(txn, c.getId(), g.getId(), SHARED);
 		// Attach the contact ID to the group
-		BdfDictionary meta = new BdfDictionary();
+		clientHelper.setContactId(txn, g.getId(), c.getId());
-		meta.put(GROUP_KEY_CONTACT_ID, c.getId().getInt());
-		try {
-			clientHelper.mergeGroupMetadata(txn, g.getId(), meta);
-		} catch (FormatException e) {
-			throw new AssertionError(e);
-		}
 		// Create and store the first local update
 		List<ClientVersion> versions = new ArrayList<>(clients);
 		Collections.sort(versions);
@@ -229,7 +222,7 @@ class ClientVersioningManagerImpl implements ClientVersioningManager,
 			Map<ClientMajorVersion, Visibility> after =
 					getVisibilities(newLocalStates, newRemoteStates);
 			// Call hooks for any visibilities that have changed
-			ContactId c = getContactId(txn, m.getGroupId());
+			ContactId c = clientHelper.getContactId(txn, m.getGroupId());
 			if (!before.equals(after)) {
 				Contact contact = db.getContact(txn, c);
 				callVisibilityHooks(txn, contact, before, after);
@@ -521,17 +514,6 @@ class ClientVersioningManagerImpl implements ClientVersioningManager,
 		storeUpdate(txn, g, states, 1);
 	}
 
-	private ContactId getContactId(Transaction txn, GroupId g)
-			throws DbException {
-		try {
-			BdfDictionary meta =
-					clientHelper.getGroupMetadataAsDictionary(txn, g);
-			return new ContactId(meta.getLong(GROUP_KEY_CONTACT_ID).intValue());
-		} catch (FormatException e) {
-			throw new DbException(e);
-		}
-	}
-
 	private List<ClientState> updateStatesFromRemoteStates(
 			List<ClientState> oldLocalStates, List<ClientState> remoteStates) {
 		Set<ClientMajorVersion> remoteSet = new HashSet<>();

bramble-core/src/test/java/org/briarproject/bramble/versioning/ClientVersioningManagerImplTest.java

@@ -38,7 +38,6 @@ import static org.briarproject.bramble.test.TestUtils.getContact;
 import static org.briarproject.bramble.test.TestUtils.getGroup;
 import static org.briarproject.bramble.test.TestUtils.getMessage;
 import static org.briarproject.bramble.test.TestUtils.getRandomId;
-import static org.briarproject.bramble.versioning.ClientVersioningConstants.GROUP_KEY_CONTACT_ID;
 import static org.briarproject.bramble.versioning.ClientVersioningConstants.MSG_KEY_LOCAL;
 import static org.briarproject.bramble.versioning.ClientVersioningConstants.MSG_KEY_UPDATE_VERSION;
 import static org.junit.Assert.assertEquals;
@@ -60,8 +59,6 @@ public class ClientVersioningManagerImplTest extends BrambleMockTestCase {
 	private final ClientId clientId = getClientId();
 	private final long now = System.currentTimeMillis();
 	private final Transaction txn = new Transaction(null, false);
-	private final BdfDictionary groupMeta = BdfDictionary.of(
-			new BdfEntry(GROUP_KEY_CONTACT_ID, contact.getId().getInt()));
 
 	private ClientVersioningManagerImpl createInstance() {
 		context.checking(new Expectations() {{
@@ -123,8 +120,8 @@ public class ClientVersioningManagerImplTest extends BrambleMockTestCase {
 			oneOf(db).addGroup(txn, contactGroup);
 			oneOf(db).setGroupVisibility(txn, contact.getId(),
 					contactGroup.getId(), SHARED);
-			oneOf(clientHelper).mergeGroupMetadata(txn, contactGroup.getId(),
+			oneOf(clientHelper).setContactId(txn, contactGroup.getId(),
-					groupMeta);
+					contact.getId());
 			oneOf(clock).currentTimeMillis();
 			will(returnValue(now));
 			oneOf(clientHelper).createMessage(contactGroup.getId(), now,
@@ -460,9 +457,8 @@ public class ClientVersioningManagerImplTest extends BrambleMockTestCase {
 			oneOf(db).deleteMessage(txn, oldRemoteUpdateId);
 			oneOf(db).deleteMessageMetadata(txn, oldRemoteUpdateId);
 			// Get contact ID
-			oneOf(clientHelper).getGroupMetadataAsDictionary(txn,
+			oneOf(clientHelper).getContactId(txn, contactGroup.getId());
-					contactGroup.getId());
+			will(returnValue(contact.getId()));
-			will(returnValue(groupMeta));
 			// No states or visibilities have changed
 		}});
 
@@ -492,10 +488,9 @@ public class ClientVersioningManagerImplTest extends BrambleMockTestCase {
 			// Load the latest local update
 			oneOf(clientHelper).getMessageAsList(txn, oldLocalUpdateId);
 			will(returnValue(oldLocalUpdateBody));
-			// Get client ID
+			// Get contact ID
-			oneOf(clientHelper).getGroupMetadataAsDictionary(txn,
+			oneOf(clientHelper).getContactId(txn, contactGroup.getId());
-					contactGroup.getId());
+			will(returnValue(contact.getId()));
-			will(returnValue(groupMeta));
 			// No states or visibilities have changed
 		}});
 
@@ -546,8 +541,6 @@ public class ClientVersioningManagerImplTest extends BrambleMockTestCase {
 		BdfDictionary newLocalUpdateMeta = BdfDictionary.of(
 				new BdfEntry(MSG_KEY_UPDATE_VERSION, 2L),
 				new BdfEntry(MSG_KEY_LOCAL, true));
-		BdfDictionary groupMeta = BdfDictionary.of(
-				new BdfEntry(GROUP_KEY_CONTACT_ID, contact.getId().getInt()));
 
 		context.checking(new Expectations() {{
 			oneOf(clientHelper).toList(newRemoteUpdate);
@@ -577,9 +570,8 @@ public class ClientVersioningManagerImplTest extends BrambleMockTestCase {
 			oneOf(clientHelper).addLocalMessage(txn, newLocalUpdate,
 					newLocalUpdateMeta, true, false);
 			// The client's visibility has changed
-			oneOf(clientHelper).getGroupMetadataAsDictionary(txn,
+			oneOf(clientHelper).getContactId(txn, contactGroup.getId());
-					contactGroup.getId());
+			will(returnValue(contact.getId()));
-			will(returnValue(groupMeta));
 			oneOf(db).getContact(txn, contact.getId());
 			will(returnValue(contact));
 			oneOf(hook).onClientVisibilityChanging(txn, contact, visibility);
@@ -619,8 +611,6 @@ public class ClientVersioningManagerImplTest extends BrambleMockTestCase {
 		BdfDictionary newLocalUpdateMeta = BdfDictionary.of(
 				new BdfEntry(MSG_KEY_UPDATE_VERSION, 2L),
 				new BdfEntry(MSG_KEY_LOCAL, true));
-		BdfDictionary groupMeta = BdfDictionary.of(
-				new BdfEntry(GROUP_KEY_CONTACT_ID, contact.getId().getInt()));
 
 		context.checking(new Expectations() {{
 			oneOf(clientHelper).toList(newRemoteUpdate);
@@ -650,9 +640,8 @@ public class ClientVersioningManagerImplTest extends BrambleMockTestCase {
 			oneOf(clientHelper).addLocalMessage(txn, newLocalUpdate,
 					newLocalUpdateMeta, true, false);
 			// The client's visibility has changed
-			oneOf(clientHelper).getGroupMetadataAsDictionary(txn,
+			oneOf(clientHelper).getContactId(txn, contactGroup.getId());
-					contactGroup.getId());
+			will(returnValue(contact.getId()));
-			will(returnValue(groupMeta));
 			oneOf(db).getContact(txn, contact.getId());
 			will(returnValue(contact));
 			oneOf(hook).onClientVisibilityChanging(txn, contact, INVISIBLE);

briar-core/src/main/java/org/briarproject/briar/introduction/AbstractProtocolEngine.java

@@ -36,7 +36,6 @@ import javax.annotation.concurrent.Immutable;
 import static org.briarproject.bramble.api.autodelete.AutoDeleteConstants.NO_AUTO_DELETE_TIMER;
 import static org.briarproject.briar.api.introduction.IntroductionManager.CLIENT_ID;
 import static org.briarproject.briar.api.introduction.IntroductionManager.MAJOR_VERSION;
-import static org.briarproject.briar.introduction.IntroductionConstants.GROUP_KEY_CONTACT_ID;
 import static org.briarproject.briar.introduction.MessageType.ABORT;
 import static org.briarproject.briar.introduction.MessageType.ACCEPT;
 import static org.briarproject.briar.introduction.MessageType.ACTIVATE;
@@ -237,10 +236,7 @@ abstract class AbstractProtocolEngine<S extends Session<?>>
 	boolean contactSupportsAutoDeletion(Transaction txn, GroupId contactGroupId)
 			throws DbException {
 		try {
-			BdfDictionary meta = clientHelper
+			ContactId c = clientHelper.getContactId(txn, contactGroupId);
-					.getGroupMetadataAsDictionary(txn, contactGroupId);
-			int contactId = meta.getLong(GROUP_KEY_CONTACT_ID).intValue();
-			ContactId c = new ContactId(contactId);
 			int minorVersion = clientVersioningManager
 					.getClientMinorVersion(txn, c, CLIENT_ID, MAJOR_VERSION);
 			// Auto-delete was added in client version 0.1

briar-core/src/main/java/org/briarproject/briar/introduction/IntroductionConstants.java

@@ -2,9 +2,6 @@ package org.briarproject.briar.introduction;
 
 interface IntroductionConstants {
 
-	// Group metadata keys
-	String GROUP_KEY_CONTACT_ID = "contactId";
-
 	// Message metadata keys
 	String MSG_KEY_MESSAGE_TYPE = "messageType";
 	String MSG_KEY_SESSION_ID = "sessionId";

briar-core/src/main/java/org/briarproject/briar/introduction/IntroductionManagerImpl.java

@@ -59,7 +59,6 @@ import static org.briarproject.briar.introduction.IntroduceeState.REMOTE_DECLINE
 import static org.briarproject.briar.introduction.IntroducerState.A_DECLINED;
 import static org.briarproject.briar.introduction.IntroducerState.B_DECLINED;
 import static org.briarproject.briar.introduction.IntroducerState.START;
-import static org.briarproject.briar.introduction.IntroductionConstants.GROUP_KEY_CONTACT_ID;
 import static org.briarproject.briar.introduction.MessageType.ABORT;
 import static org.briarproject.briar.introduction.MessageType.ACCEPT;
 import static org.briarproject.briar.introduction.MessageType.ACTIVATE;
@@ -136,13 +135,7 @@ class IntroductionManagerImpl extends ConversationClientImpl
 				c.getId(), CLIENT_ID, MAJOR_VERSION);
 		db.setGroupVisibility(txn, c.getId(), g.getId(), client);
 		// Attach the contact ID to the group
-		BdfDictionary meta = new BdfDictionary();
+		clientHelper.setContactId(txn, g.getId(), c.getId());
-		meta.put(GROUP_KEY_CONTACT_ID, c.getId().getInt());
-		try {
-			clientHelper.mergeGroupMetadata(txn, g.getId(), meta);
-		} catch (FormatException e) {
-			throw new AssertionError(e);
-		}
 	}
 
 	@Override
@@ -183,7 +176,7 @@ class IntroductionManagerImpl extends ConversationClientImpl
 		}
 		StoredSession ss = getSession(txn, sessionId);
 		// Handle the message
-		Session session;
+		Session<?> session;
 		MessageId storageId;
 		if (ss == null) {
 			if (meta.getMessageType() != REQUEST) throw new FormatException();
@@ -211,7 +204,7 @@ class IntroductionManagerImpl extends ConversationClientImpl
 
 	private IntroduceeSession createNewIntroduceeSession(Transaction txn,
 			Message m, BdfList body) throws DbException, FormatException {
-		ContactId introducerId = getContactId(txn, m.getGroupId());
+		ContactId introducerId = clientHelper.getContactId(txn, m.getGroupId());
 		Author introducer = db.getContact(txn, introducerId).getAuthor();
 		Author local = identityManager.getLocalAuthor(txn);
 		Author remote = messageParser.parseRequestMessage(m, body).getAuthor();
@@ -223,7 +216,7 @@ class IntroductionManagerImpl extends ConversationClientImpl
 						remote);
 	}
 
-	private <S extends Session> S handleMessage(Transaction txn, Message m,
+	private <S extends Session<?>> S handleMessage(Transaction txn, Message m,
 			BdfList body, MessageType type, S session, ProtocolEngine<S> engine)
 			throws DbException, FormatException {
 		if (type == REQUEST) {
@@ -263,13 +256,6 @@ class IntroductionManagerImpl extends ConversationClientImpl
 				results.values().iterator().next());
 	}
 
-	private ContactId getContactId(Transaction txn, GroupId contactGroupId)
-			throws DbException, FormatException {
-		BdfDictionary meta =
-				clientHelper.getGroupMetadataAsDictionary(txn, contactGroupId);
-		return new ContactId(meta.getLong(GROUP_KEY_CONTACT_ID).intValue());
-	}
-
 	private MessageId createStorageId(Transaction txn) throws DbException {
 		Message m = clientHelper
 				.createMessageForStoringMetadata(localGroup.getId());
@@ -278,7 +264,7 @@ class IntroductionManagerImpl extends ConversationClientImpl
 	}
 
 	private void storeSession(Transaction txn, MessageId storageId,
-			Session session) throws DbException {
+			Session<?> session) throws DbException {
 		BdfDictionary d;
 		if (session.getRole() == INTRODUCER) {
 			d = sessionEncoder
@@ -666,7 +652,7 @@ class IntroductionManagerImpl extends ConversationClientImpl
 		try {
 			StoredSession ss = getSession(txn, sessionId);
 			if (ss == null) throw new AssertionError();
-			Session s;
+			Session<?> s;
 			Role role = sessionParser.getRole(ss.bdfSession);
 			if (role == INTRODUCER) {
 				s = sessionParser.parseIntroducerSession(ss.bdfSession);

briar-core/src/main/java/org/briarproject/briar/messaging/MessagingConstants.java

@@ -2,9 +2,6 @@ package org.briarproject.briar.messaging;
 
 interface MessagingConstants {
 
-	// Metadata keys for groups
-	String GROUP_KEY_CONTACT_ID = "contactId";
-
 	// Metadata keys for messages
 	String MSG_KEY_TIMESTAMP = "timestamp";
 	String MSG_KEY_LOCAL = "local";

briar-core/src/main/java/org/briarproject/briar/messaging/MessagingManagerImpl.java

@@ -68,7 +68,6 @@ import static org.briarproject.briar.api.messaging.PrivateMessageFormat.TEXT_ONL
 import static org.briarproject.briar.client.MessageTrackerConstants.MSG_KEY_READ;
 import static org.briarproject.briar.messaging.MessageTypes.ATTACHMENT;
 import static org.briarproject.briar.messaging.MessageTypes.PRIVATE_MESSAGE;
-import static org.briarproject.briar.messaging.MessagingConstants.GROUP_KEY_CONTACT_ID;
 import static org.briarproject.briar.messaging.MessagingConstants.MSG_KEY_ATTACHMENT_HEADERS;
 import static org.briarproject.briar.messaging.MessagingConstants.MSG_KEY_AUTO_DELETE_TIMER;
 import static org.briarproject.briar.messaging.MessagingConstants.MSG_KEY_CONTENT_TYPE;
@@ -139,13 +138,7 @@ class MessagingManagerImpl implements MessagingManager, IncomingMessageHook,
 				c.getId(), CLIENT_ID, MAJOR_VERSION);
 		db.setGroupVisibility(txn, c.getId(), g.getId(), client);
 		// Attach the contact ID to the group
-		BdfDictionary d = new BdfDictionary();
+		clientHelper.setContactId(txn, g.getId(), c.getId());
-		d.put(GROUP_KEY_CONTACT_ID, c.getId().getInt());
-		try {
-			clientHelper.mergeGroupMetadata(txn, g.getId(), d);
-		} catch (FormatException e) {
-			throw new AssertionError(e);
-		}
 		// Initialize the group count with current time
 		messageTracker.initializeGroupCount(txn, g.getId());
 	}

briar-core/src/main/java/org/briarproject/briar/privategroup/invitation/AbstractProtocolEngine.java

@@ -31,7 +31,6 @@ import javax.annotation.Nullable;
 import javax.annotation.concurrent.Immutable;
 
 import static org.briarproject.bramble.api.autodelete.AutoDeleteConstants.NO_AUTO_DELETE_TIMER;
-import static org.briarproject.briar.privategroup.invitation.GroupInvitationConstants.GROUP_KEY_CONTACT_ID;
 import static org.briarproject.briar.privategroup.invitation.MessageType.ABORT;
 import static org.briarproject.briar.privategroup.invitation.MessageType.INVITE;
 import static org.briarproject.briar.privategroup.invitation.MessageType.JOIN;
@@ -76,13 +75,6 @@ abstract class AbstractProtocolEngine<S extends Session<?>>
 		this.clock = clock;
 	}
 
-	ContactId getContactId(Transaction txn, GroupId contactGroupId)
-			throws DbException, FormatException {
-		BdfDictionary meta = clientHelper.getGroupMetadataAsDictionary(txn,
-				contactGroupId);
-		return new ContactId(meta.getLong(GROUP_KEY_CONTACT_ID).intValue());
-	}
-
 	boolean isSubscribedPrivateGroup(Transaction txn, GroupId g)
 			throws DbException {
 		if (!db.containsGroup(txn, g)) return false;
@@ -100,7 +92,8 @@ abstract class AbstractProtocolEngine<S extends Session<?>>
 	void setPrivateGroupVisibility(Transaction txn, S session,
 			Visibility preferred) throws DbException, FormatException {
 		// Apply min of preferred visibility and client's visibility
-		ContactId contactId = getContactId(txn, session.getContactGroupId());
+		ContactId contactId =
+				clientHelper.getContactId(txn, session.getContactGroupId());
 		Visibility client = clientVersioningManager.getClientVisibility(txn,
 				contactId, PrivateGroupManager.CLIENT_ID,
 				PrivateGroupManager.MAJOR_VERSION);
@@ -273,10 +266,7 @@ abstract class AbstractProtocolEngine<S extends Session<?>>
 	boolean contactSupportsAutoDeletion(Transaction txn, GroupId contactGroupId)
 			throws DbException {
 		try {
-			BdfDictionary meta = clientHelper
+			ContactId c = clientHelper.getContactId(txn, contactGroupId);
-					.getGroupMetadataAsDictionary(txn, contactGroupId);
-			int contactId = meta.getLong(GROUP_KEY_CONTACT_ID).intValue();
-			ContactId c = new ContactId(contactId);
 			int minorVersion = clientVersioningManager
 					.getClientMinorVersion(txn, c,
 							GroupInvitationManager.CLIENT_ID,

briar-core/src/main/java/org/briarproject/briar/privategroup/invitation/CreatorProtocolEngine.java

@@ -191,7 +191,8 @@ class CreatorProtocolEngine extends AbstractProtocolEngine<CreatorSession> {
 		// Share the private group with the contact
 		setPrivateGroupVisibility(txn, s, SHARED);
 		// Broadcast an event
-		ContactId contactId = getContactId(txn, m.getContactGroupId());
+		ContactId contactId =
+				clientHelper.getContactId(txn, m.getContactGroupId());
 		txn.attach(new GroupInvitationResponseReceivedEvent(
 				createInvitationResponse(m, true), contactId));
 		// Move to the JOINED state
@@ -213,7 +214,8 @@ class CreatorProtocolEngine extends AbstractProtocolEngine<CreatorSession> {
 		messageTracker.trackMessage(txn, m.getContactGroupId(),
 				m.getTimestamp(), false);
 		// Broadcast an event
-		ContactId contactId = getContactId(txn, m.getContactGroupId());
+		ContactId contactId =
+				clientHelper.getContactId(txn, m.getContactGroupId());
 		txn.attach(new GroupInvitationResponseReceivedEvent(
 				createInvitationResponse(m, false), contactId));
 		// Move to the START state

briar-core/src/main/java/org/briarproject/briar/privategroup/invitation/GroupInvitationConstants.java

@@ -2,9 +2,6 @@ package org.briarproject.briar.privategroup.invitation;
 
 interface GroupInvitationConstants {
 
-	// Group metadata keys
-	String GROUP_KEY_CONTACT_ID = "contactId";
-
 	// Message metadata keys
 	String MSG_KEY_MESSAGE_TYPE = "messageType";
 	String MSG_KEY_PRIVATE_GROUP_ID = "privateGroupId";

briar-core/src/main/java/org/briarproject/briar/privategroup/invitation/GroupInvitationManagerImpl.java

@@ -53,7 +53,6 @@ import javax.inject.Inject;
 
 import static org.briarproject.bramble.api.sync.Group.Visibility.SHARED;
 import static org.briarproject.briar.privategroup.invitation.CreatorState.START;
-import static org.briarproject.briar.privategroup.invitation.GroupInvitationConstants.GROUP_KEY_CONTACT_ID;
 import static org.briarproject.briar.privategroup.invitation.MessageType.ABORT;
 import static org.briarproject.briar.privategroup.invitation.MessageType.INVITE;
 import static org.briarproject.briar.privategroup.invitation.MessageType.JOIN;
@@ -123,13 +122,7 @@ class GroupInvitationManagerImpl extends ConversationClientImpl
 				c.getId(), CLIENT_ID, MAJOR_VERSION);
 		db.setGroupVisibility(txn, c.getId(), g.getId(), client);
 		// Attach the contact ID to the group
-		BdfDictionary meta = new BdfDictionary();
+		clientHelper.setContactId(txn, g.getId(), c.getId());
-		meta.put(GROUP_KEY_CONTACT_ID, c.getId().getInt());
-		try {
-			clientHelper.mergeGroupMetadata(txn, g.getId(), meta);
-		} catch (FormatException e) {
-			throw new AssertionError(e);
-		}
 		// If the contact belongs to any private groups, create a peer session
 		for (Group pg : db.getGroups(txn, PrivateGroupManager.CLIENT_ID,
 				PrivateGroupManager.MAJOR_VERSION)) {
@@ -189,7 +182,8 @@ class GroupInvitationManagerImpl extends ConversationClientImpl
 				results.values().iterator().next());
 	}
 
-	private Session<?> handleFirstMessage(Transaction txn, Message m, BdfList body,
+	private Session<?> handleFirstMessage(Transaction txn, Message m,
+			BdfList body,
 			MessageMetadata meta) throws DbException, FormatException {
 		GroupId privateGroupId = meta.getPrivateGroupId();
 		MessageType type = meta.getMessageType();

briar-core/src/main/java/org/briarproject/briar/privategroup/invitation/InviteeProtocolEngine.java

@@ -230,7 +230,8 @@ class InviteeProtocolEngine extends AbstractProtocolEngine<InviteeSession> {
 		// The timestamp must be higher than the last invite message, if any
 		if (m.getTimestamp() <= s.getInviteTimestamp()) return abort(txn, s);
 		// Check that the contact is the creator
-		ContactId contactId = getContactId(txn, s.getContactGroupId());
+		ContactId contactId =
+				clientHelper.getContactId(txn, s.getContactGroupId());
 		Author contact = db.getContact(txn, contactId).getAuthor();
 		if (!contact.getId().equals(m.getCreator().getId()))
 			return abort(txn, s);

briar-core/src/main/java/org/briarproject/briar/privategroup/invitation/PeerProtocolEngine.java

@@ -355,7 +355,8 @@ class PeerProtocolEngine extends AbstractProtocolEngine<PeerSession> {
 
 	private void relationshipRevealed(Transaction txn, PeerSession s,
 			boolean byContact) throws DbException, FormatException {
-		ContactId contactId = getContactId(txn, s.getContactGroupId());
+		ContactId contactId =
+				clientHelper.getContactId(txn, s.getContactGroupId());
 		Contact contact = db.getContact(txn, contactId);
 		privateGroupManager.relationshipRevealed(txn, s.getPrivateGroupId(),
 				contact.getAuthor().getId(), byContact);

briar-core/src/main/java/org/briarproject/briar/sharing/ProtocolEngineImpl.java

@@ -37,7 +37,6 @@ import static org.briarproject.briar.sharing.MessageType.ACCEPT;
 import static org.briarproject.briar.sharing.MessageType.DECLINE;
 import static org.briarproject.briar.sharing.MessageType.INVITE;
 import static org.briarproject.briar.sharing.MessageType.LEAVE;
-import static org.briarproject.briar.sharing.SharingConstants.GROUP_KEY_CONTACT_ID;
 import static org.briarproject.briar.sharing.State.LOCAL_INVITED;
 import static org.briarproject.briar.sharing.State.LOCAL_LEFT;
 import static org.briarproject.briar.sharing.State.REMOTE_HANGING;
@@ -341,7 +340,8 @@ abstract class ProtocolEngineImpl<S extends Shareable>
 		messageTracker.trackMessage(txn, m.getContactGroupId(),
 				m.getTimestamp(), false);
 		// Broadcast an event
-		ContactId contactId = getContactId(txn, s.getContactGroupId());
+		ContactId contactId =
+				clientHelper.getContactId(txn, s.getContactGroupId());
 		txn.attach(getInvitationRequestReceivedEvent(m, contactId, available,
 				false));
 		// Move to the next state
@@ -367,7 +367,8 @@ abstract class ProtocolEngineImpl<S extends Shareable>
 		// Share the shareable with the contact
 		setShareableVisibility(txn, s, SHARED);
 		// Broadcast an event
-		ContactId contactId = getContactId(txn, s.getContactGroupId());
+		ContactId contactId =
+				clientHelper.getContactId(txn, s.getContactGroupId());
 		txn.attach(
 				getInvitationRequestReceivedEvent(m, contactId, false, true));
 		// Move to the next state
@@ -411,7 +412,8 @@ abstract class ProtocolEngineImpl<S extends Shareable>
 		messageTracker.trackMessage(txn, m.getContactGroupId(),
 				m.getTimestamp(), false);
 		// Broadcast an event
-		ContactId contactId = getContactId(txn, m.getContactGroupId());
+		ContactId contactId =
+				clientHelper.getContactId(txn, m.getContactGroupId());
 		txn.attach(getInvitationResponseReceivedEvent(m, contactId));
 		// Move to the next state
 		return new Session(nextState, s.getContactGroupId(), s.getShareableId(),
@@ -469,7 +471,8 @@ abstract class ProtocolEngineImpl<S extends Shareable>
 			throw new DbException(e); // Invalid group metadata
 		}
 		// Broadcast an event
-		ContactId contactId = getContactId(txn, m.getContactGroupId());
+		ContactId contactId =
+				clientHelper.getContactId(txn, m.getContactGroupId());
 		txn.attach(getInvitationResponseReceivedEvent(m, contactId));
 		// Move to the next state
 		return new Session(START, s.getContactGroupId(), s.getShareableId(),
@@ -529,7 +532,8 @@ abstract class ProtocolEngineImpl<S extends Shareable>
 		if (isInvalidDependency(s, m.getPreviousMessageId()))
 			return abortWithMessage(txn, s);
 		// Broadcast event informing that contact left
-		ContactId contactId = getContactId(txn, s.getContactGroupId());
+		ContactId contactId =
+				clientHelper.getContactId(txn, s.getContactGroupId());
 		ContactLeftShareableEvent e = new ContactLeftShareableEvent(
 				s.getShareableId(), contactId);
 		txn.attach(e);
@@ -648,20 +652,14 @@ abstract class ProtocolEngineImpl<S extends Shareable>
 	private void setShareableVisibility(Transaction txn, Session session,
 			Visibility preferred) throws DbException, FormatException {
 		// Apply min of preferred visibility and client's visibility
-		ContactId contactId = getContactId(txn, session.getContactGroupId());
+		ContactId contactId =
+				clientHelper.getContactId(txn, session.getContactGroupId());
 		Visibility client = clientVersioningManager.getClientVisibility(txn,
 				contactId, shareableClientId, shareableClientMajorVersion);
 		Visibility min = Visibility.min(preferred, client);
 		db.setGroupVisibility(txn, contactId, session.getShareableId(), min);
 	}
 
-	private ContactId getContactId(Transaction txn, GroupId contactGroupId)
-			throws DbException, FormatException {
-		BdfDictionary meta = clientHelper.getGroupMetadataAsDictionary(txn,
-				contactGroupId);
-		return new ContactId(meta.getLong(GROUP_KEY_CONTACT_ID).intValue());
-	}
-
 	private boolean isInvalidDependency(Session session,
 			@Nullable MessageId dependency) {
 		MessageId expected = session.getLastRemoteMessageId();
@@ -678,10 +676,7 @@ abstract class ProtocolEngineImpl<S extends Shareable>
 	boolean contactSupportsAutoDeletion(Transaction txn, GroupId contactGroupId)
 			throws DbException {
 		try {
-			BdfDictionary meta = clientHelper
+			ContactId c = clientHelper.getContactId(txn, contactGroupId);
-					.getGroupMetadataAsDictionary(txn, contactGroupId);
-			int contactId = meta.getLong(GROUP_KEY_CONTACT_ID).intValue();
-			ContactId c = new ContactId(contactId);
 			int minorVersion = clientVersioningManager
 					.getClientMinorVersion(txn, c, sharingClientId,
 							sharingClientMajorVersion);

briar-core/src/main/java/org/briarproject/briar/sharing/SharingConstants.java

@@ -4,9 +4,6 @@ import org.briarproject.briar.client.MessageTrackerConstants;
 
 interface SharingConstants {
 
-	// Group metadata keys
-	String GROUP_KEY_CONTACT_ID = "contactId";
-
 	// Message metadata keys
 	String MSG_KEY_MESSAGE_TYPE = "messageType";
 	String MSG_KEY_SHAREABLE_ID = "shareableId";

briar-core/src/main/java/org/briarproject/briar/sharing/SharingManagerImpl.java

@@ -52,7 +52,6 @@ import static org.briarproject.briar.sharing.MessageType.ACCEPT;
 import static org.briarproject.briar.sharing.MessageType.DECLINE;
 import static org.briarproject.briar.sharing.MessageType.INVITE;
 import static org.briarproject.briar.sharing.MessageType.LEAVE;
-import static org.briarproject.briar.sharing.SharingConstants.GROUP_KEY_CONTACT_ID;
 import static org.briarproject.briar.sharing.State.SHARING;
 
 @NotNullByDefault
@@ -114,13 +113,7 @@ abstract class SharingManagerImpl<S extends Shareable>
 				c.getId(), getClientId(), getMajorVersion());
 		db.setGroupVisibility(txn, c.getId(), g.getId(), client);
 		// Attach the contact ID to the group
-		BdfDictionary meta = new BdfDictionary();
+		clientHelper.setContactId(txn, g.getId(), c.getId());
-		meta.put(GROUP_KEY_CONTACT_ID, c.getId().getInt());
-		try {
-			clientHelper.mergeGroupMetadata(txn, g.getId(), meta);
-		} catch (FormatException e) {
-			throw new AssertionError(e);
-		}
 	}
 
 	@Override

briar-core/src/test/java/org/briarproject/briar/privategroup/invitation/AbstractProtocolEngineTest.java

@@ -37,7 +37,6 @@ import static org.briarproject.bramble.util.StringUtils.getRandomString;
 import static org.briarproject.briar.api.privategroup.PrivateGroupConstants.GROUP_SALT_LENGTH;
 import static org.briarproject.briar.api.privategroup.PrivateGroupConstants.MAX_GROUP_INVITATION_TEXT_LENGTH;
 import static org.briarproject.briar.api.privategroup.PrivateGroupConstants.MAX_GROUP_NAME_LENGTH;
-import static org.briarproject.briar.privategroup.invitation.GroupInvitationConstants.GROUP_KEY_CONTACT_ID;
 import static org.briarproject.briar.privategroup.invitation.MessageType.ABORT;
 import static org.briarproject.briar.privategroup.invitation.MessageType.INVITE;
 import static org.briarproject.briar.privategroup.invitation.MessageType.JOIN;
@@ -81,8 +80,6 @@ abstract class AbstractProtocolEngineTest extends BrambleMockTestCase {
 	final long messageTimestamp = message.getTimestamp();
 	final long inviteTimestamp = messageTimestamp - 1;
 	final long localTimestamp = inviteTimestamp - 1;
-	final BdfDictionary groupMeta = BdfDictionary.of(
-			new BdfEntry(GROUP_KEY_CONTACT_ID, contactId.getInt()));
 
 	final InviteMessage inviteMessage =
 			new InviteMessage(new MessageId(getRandomId()), contactGroupId,
@@ -196,12 +193,9 @@ abstract class AbstractProtocolEngineTest extends BrambleMockTestCase {
 	}
 
 	void expectGetContactId() throws Exception {
-		BdfDictionary groupMeta = BdfDictionary
-				.of(new BdfEntry(GROUP_KEY_CONTACT_ID, contactId.getInt()));
 		context.checking(new Expectations() {{
-			oneOf(clientHelper)
+			oneOf(clientHelper).getContactId(txn, contactGroupId);
-					.getGroupMetadataAsDictionary(txn, contactGroupId);
+			will(returnValue(contactId));
-			will(returnValue(groupMeta));
 		}});
 	}
 
@@ -231,9 +225,8 @@ abstract class AbstractProtocolEngineTest extends BrambleMockTestCase {
 
 	void expectCheckWhetherContactSupportsAutoDeletion() throws Exception {
 		context.checking(new Expectations() {{
-			oneOf(clientHelper).getGroupMetadataAsDictionary(txn,
+			oneOf(clientHelper).getContactId(txn, contactGroupId);
-					contactGroupId);
+			will(returnValue(contactId));
-			will(returnValue(groupMeta));
 			oneOf(clientVersioningManager).getClientMinorVersion(txn, contactId,
 					GroupInvitationManager.CLIENT_ID,
 					GroupInvitationManager.MAJOR_VERSION);

briar-core/src/test/java/org/briarproject/briar/privategroup/invitation/GroupInvitationManagerImplTest.java

@@ -58,7 +58,6 @@ import static org.briarproject.briar.api.privategroup.PrivateGroupConstants.GROU
 import static org.briarproject.briar.api.privategroup.PrivateGroupConstants.MAX_GROUP_NAME_LENGTH;
 import static org.briarproject.briar.api.privategroup.invitation.GroupInvitationManager.CLIENT_ID;
 import static org.briarproject.briar.api.privategroup.invitation.GroupInvitationManager.MAJOR_VERSION;
-import static org.briarproject.briar.privategroup.invitation.GroupInvitationConstants.GROUP_KEY_CONTACT_ID;
 import static org.briarproject.briar.privategroup.invitation.MessageType.ABORT;
 import static org.briarproject.briar.privategroup.invitation.MessageType.INVITE;
 import static org.briarproject.briar.privategroup.invitation.MessageType.JOIN;
@@ -178,9 +177,6 @@ public class GroupInvitationManagerImplTest extends BrambleMockTestCase {
 	}
 
 	private void expectAddingContact(Contact c) throws Exception {
-		BdfDictionary meta = BdfDictionary
-				.of(new BdfEntry(GROUP_KEY_CONTACT_ID, c.getId().getInt()));
-
 		context.checking(new Expectations() {{
 			oneOf(contactGroupFactory).createContactGroup(CLIENT_ID,
 					MAJOR_VERSION, c);
@@ -192,7 +188,7 @@ public class GroupInvitationManagerImplTest extends BrambleMockTestCase {
 			oneOf(db).setGroupVisibility(txn, c.getId(), contactGroup.getId(),
 					SHARED);
 			oneOf(clientHelper)
-					.mergeGroupMetadata(txn, contactGroup.getId(), meta);
+					.setContactId(txn, contactGroup.getId(), contactId);
 			oneOf(db).getGroups(txn, PrivateGroupManager.CLIENT_ID,
 					PrivateGroupManager.MAJOR_VERSION);
 			will(returnValue(Collections.singletonList(privateGroup)));

briar-core/src/test/java/org/briarproject/briar/sharing/BlogSharingManagerImplTest.java

@@ -5,7 +5,6 @@ import org.briarproject.bramble.api.client.ContactGroupFactory;
 import org.briarproject.bramble.api.contact.Contact;
 import org.briarproject.bramble.api.contact.ContactId;
 import org.briarproject.bramble.api.data.BdfDictionary;
-import org.briarproject.bramble.api.data.BdfEntry;
 import org.briarproject.bramble.api.data.MetadataParser;
 import org.briarproject.bramble.api.db.DatabaseComponent;
 import org.briarproject.bramble.api.db.DbException;
@@ -41,7 +40,6 @@ import static org.briarproject.bramble.test.TestUtils.getMessage;
 import static org.briarproject.bramble.test.TestUtils.getRandomId;
 import static org.briarproject.briar.api.blog.BlogSharingManager.CLIENT_ID;
 import static org.briarproject.briar.api.blog.BlogSharingManager.MAJOR_VERSION;
-import static org.briarproject.briar.sharing.SharingConstants.GROUP_KEY_CONTACT_ID;
 
 public class BlogSharingManagerImplTest extends BrambleMockTestCase {
 
@@ -117,8 +115,6 @@ public class BlogSharingManagerImplTest extends BrambleMockTestCase {
 	}
 
 	private void expectAddingContact(Transaction txn) throws Exception {
-		BdfDictionary meta = BdfDictionary.of(
-				new BdfEntry(GROUP_KEY_CONTACT_ID, contactId.getInt()));
 		Map<MessageId, BdfDictionary> sessions = Collections.emptyMap();
 
 		context.checking(new Expectations() {{
@@ -134,7 +130,7 @@ public class BlogSharingManagerImplTest extends BrambleMockTestCase {
 					SHARED);
 			// Attach the contact ID to the group
 			oneOf(clientHelper)
-					.mergeGroupMetadata(txn, contactGroup.getId(), meta);
+					.setContactId(txn, contactGroup.getId(), contactId);
 			// Get our blog and the contact's blog
 			oneOf(identityManager).getLocalAuthor(txn);
 			will(returnValue(localAuthor));