Replace ETA with max latency in retransmission logic

bramble-core/src/main/java/org/briarproject/bramble/db/Database.java

@@ -758,9 +758,10 @@ interface Database<T> {
 	void resetExpiryTime(T txn, ContactId c, MessageId m) throws DbException;
 
 	/**
-	 * Resets the transmission count, expiry time and ETA of all messages that
-	 * are eligible to be sent to the given contact. This includes messages that
-	 * have already been sent and are not yet due for retransmission.
+	 * Resets the transmission count, expiry time and max latency of all
+	 * messages that are eligible to be sent to the given contact. This includes
+	 * messages that have already been sent and are not yet due for
+	 * retransmission.
 	 */
 	void resetUnackedMessagesToSend(T txn, ContactId c) throws DbException;
 
@@ -848,11 +849,13 @@ interface Database<T> {
 	void stopCleanupTimer(T txn, MessageId m) throws DbException;
 
 	/**
-	 * Updates the transmission count, expiry time and estimated time of arrival
-	 * of the given message with respect to the given contact, using the latency
-	 * of the transport over which it was sent.
+	 * Updates the transmission count, expiry time and max latency of the given
+	 * message with respect to the given contact.
+	 *
+	 * @param maxLatency latency of the transport over which the message was
+	 * sent.
 	 */
-	void updateExpiryTimeAndEta(T txn, ContactId c, MessageId m,
+	void updateRetransmissionData(T txn, ContactId c, MessageId m,
 			long maxLatency) throws DbException;
 
 	/**

bramble-core/src/main/java/org/briarproject/bramble/db/DatabaseComponentImpl.java

@@ -437,7 +437,7 @@ class DatabaseComponentImpl<T> implements DatabaseComponent {
 			Message message = db.getMessage(txn, m);
 			totalLength += message.getRawLength();
 			messages.add(message);
-			db.updateExpiryTimeAndEta(txn, c, m, maxLatency);
+			db.updateRetransmissionData(txn, c, m, maxLatency);
 		}
 		if (ids.isEmpty()) return null;
 		db.lowerRequestedFlag(txn, c, ids);
@@ -462,7 +462,7 @@ class DatabaseComponentImpl<T> implements DatabaseComponent {
 				totalLength += message.getRawLength();
 				messages.add(message);
 				sentIds.add(m);
-				db.updateExpiryTimeAndEta(txn, c, m, maxLatency);
+				db.updateRetransmissionData(txn, c, m, maxLatency);
 			}
 		}
 		if (messages.isEmpty()) return messages;
@@ -483,7 +483,7 @@ class DatabaseComponentImpl<T> implements DatabaseComponent {
 				db.getMessagesToOffer(txn, c, maxMessages, maxLatency);
 		if (ids.isEmpty()) return null;
 		for (MessageId m : ids)
-			db.updateExpiryTimeAndEta(txn, c, m, maxLatency);
+			db.updateRetransmissionData(txn, c, m, maxLatency);
 		return new Offer(ids);
 	}
 
@@ -518,7 +518,7 @@ class DatabaseComponentImpl<T> implements DatabaseComponent {
 			Message message = db.getMessage(txn, m);
 			totalLength += message.getRawLength();
 			messages.add(message);
-			db.updateExpiryTimeAndEta(txn, c, m, maxLatency);
+			db.updateRetransmissionData(txn, c, m, maxLatency);
 		}
 		if (ids.isEmpty()) return null;
 		db.lowerRequestedFlag(txn, c, ids);

bramble-core/src/main/java/org/briarproject/bramble/db/JdbcDatabase.java

@@ -102,7 +102,7 @@ import static org.briarproject.bramble.util.LogUtils.now;
 abstract class JdbcDatabase implements Database<Connection> {
 
 	// Package access for testing
-	static final int CODE_SCHEMA_VERSION = 49;
+	static final int CODE_SCHEMA_VERSION = 50;
 
 	// Time period offsets for incoming transport keys
 	private static final int OFFSET_PREV = -1;
@@ -252,7 +252,7 @@ abstract class JdbcDatabase implements Database<Connection> {
 					+ " requested BOOLEAN NOT NULL,"
 					+ " expiry BIGINT NOT NULL,"
 					+ " txCount INT NOT NULL,"
-					+ " eta BIGINT NOT NULL,"
+					+ " maxLatency BIGINT," // Null if latency was reset
 					+ " PRIMARY KEY (messageId, contactId),"
 					+ " FOREIGN KEY (messageId)"
 					+ " REFERENCES messages (messageId)"
@@ -502,7 +502,8 @@ abstract class JdbcDatabase implements Database<Connection> {
 				new Migration45_46(),
 				new Migration46_47(dbTypes),
 				new Migration47_48(),
-				new Migration48_49()
+				new Migration48_49(),
+				new Migration49_50()
 		);
 	}
 
@@ -920,9 +921,10 @@ abstract class JdbcDatabase implements Database<Connection> {
 		try {
 			String sql = "INSERT INTO statuses (messageId, contactId, groupId,"
 					+ " timestamp, length, state, groupShared, messageShared,"
-					+ " deleted, ack, seen, requested, expiry, txCount, eta)"
+					+ " deleted, ack, seen, requested, expiry, txCount,"
+					+ " maxLatency)"
 					+ " VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, FALSE, 0, 0,"
-					+ " 0)";
+					+ " NULL)";
 			ps = txn.prepareStatement(sql);
 			ps.setBytes(1, m.getBytes());
 			ps.setInt(2, c.getInt());
@@ -1156,17 +1158,17 @@ abstract class JdbcDatabase implements Database<Connection> {
 				ps.setInt(2, DELIVERED.getValue());
 			} else {
 				long now = clock.currentTimeMillis();
-				long eta = now + maxLatency;
 				sql = "SELECT NULL FROM statuses"
 						+ " WHERE contactId = ? AND state = ?"
 						+ " AND groupShared = TRUE AND messageShared = TRUE"
 						+ " AND deleted = FALSE AND seen = FALSE"
-						+ " AND (expiry <= ? OR eta > ?)";
+						+ " AND (expiry <= ? OR maxLatency IS NULL"
+						+ " OR ? < maxLatency)";
 				ps = txn.prepareStatement(sql);
 				ps.setInt(1, c.getInt());
 				ps.setInt(2, DELIVERED.getValue());
 				ps.setLong(3, now);
-				ps.setLong(4, eta);
+				ps.setLong(4, maxLatency);
 			}
 			rs = ps.executeQuery();
 			boolean messagesToSend = rs.next();
@@ -2194,7 +2196,6 @@ abstract class JdbcDatabase implements Database<Connection> {
 	public Collection<MessageId> getMessagesToOffer(Connection txn,
 			ContactId c, int maxMessages, long maxLatency) throws DbException {
 		long now = clock.currentTimeMillis();
-		long eta = now + maxLatency;
 		PreparedStatement ps = null;
 		ResultSet rs = null;
 		try {
@@ -2203,13 +2204,14 @@ abstract class JdbcDatabase implements Database<Connection> {
 					+ " AND groupShared = TRUE AND messageShared = TRUE"
 					+ " AND deleted = FALSE"
 					+ " AND seen = FALSE AND requested = FALSE"
-					+ " AND (expiry <= ? OR eta > ?)"
+					+ " AND (expiry <= ? OR maxLatency IS NULL"
+					+ " OR ? < maxLatency)"
 					+ " ORDER BY timestamp LIMIT ?";
 			ps = txn.prepareStatement(sql);
 			ps.setInt(1, c.getInt());
 			ps.setInt(2, DELIVERED.getValue());
 			ps.setLong(3, now);
-			ps.setLong(4, eta);
+			ps.setLong(4, maxLatency);
 			ps.setInt(5, maxMessages);
 			rs = ps.executeQuery();
 			List<MessageId> ids = new ArrayList<>();
@@ -2253,7 +2255,6 @@ abstract class JdbcDatabase implements Database<Connection> {
 	public Collection<MessageId> getMessagesToSend(Connection txn, ContactId c,
 			int maxLength, long maxLatency) throws DbException {
 		long now = clock.currentTimeMillis();
-		long eta = now + maxLatency;
 		PreparedStatement ps = null;
 		ResultSet rs = null;
 		try {
@@ -2262,13 +2263,14 @@ abstract class JdbcDatabase implements Database<Connection> {
 					+ " AND groupShared = TRUE AND messageShared = TRUE"
 					+ " AND deleted = FALSE"
 					+ " AND seen = FALSE"
-					+ " AND (expiry <= ? OR eta > ?)"
+					+ " AND (expiry <= ? OR maxLatency IS NULL"
+					+ " OR ? < maxLatency)"
 					+ " ORDER BY timestamp";
 			ps = txn.prepareStatement(sql);
 			ps.setInt(1, c.getInt());
 			ps.setInt(2, DELIVERED.getValue());
 			ps.setLong(3, now);
-			ps.setLong(4, eta);
+			ps.setLong(4, maxLatency);
 			rs = ps.executeQuery();
 			List<MessageId> ids = new ArrayList<>();
 			int total = 0;
@@ -2552,7 +2554,6 @@ abstract class JdbcDatabase implements Database<Connection> {
 	public Collection<MessageId> getRequestedMessagesToSend(Connection txn,
 			ContactId c, int maxLength, long maxLatency) throws DbException {
 		long now = clock.currentTimeMillis();
-		long eta = now + maxLatency;
 		PreparedStatement ps = null;
 		ResultSet rs = null;
 		try {
@@ -2561,13 +2562,14 @@ abstract class JdbcDatabase implements Database<Connection> {
 					+ " AND groupShared = TRUE AND messageShared = TRUE"
 					+ " AND deleted = FALSE"
 					+ " AND seen = FALSE AND requested = TRUE"
-					+ " AND (expiry <= ? OR eta > ?)"
+					+ " AND (expiry <= ? OR maxLatency IS NULL"
+					+ " OR ? < maxLatency)"
 					+ " ORDER BY timestamp";
 			ps = txn.prepareStatement(sql);
 			ps.setInt(1, c.getInt());
 			ps.setInt(2, DELIVERED.getValue());
 			ps.setLong(3, now);
-			ps.setLong(4, eta);
+			ps.setLong(4, maxLatency);
 			rs = ps.executeQuery();
 			List<MessageId> ids = new ArrayList<>();
 			int total = 0;
@@ -3298,7 +3300,8 @@ abstract class JdbcDatabase implements Database<Connection> {
 			throws DbException {
 		PreparedStatement ps = null;
 		try {
-			String sql = "UPDATE statuses SET expiry = 0, txCount = 0, eta = 0"
+			String sql = "UPDATE statuses SET expiry = 0, txCount = 0,"
+					+ " maxLatency = NULL"
 					+ " WHERE contactId = ? AND state = ?"
 					+ " AND groupShared = TRUE AND messageShared = TRUE"
 					+ " AND deleted = FALSE AND seen = FALSE";
@@ -3643,8 +3646,8 @@ abstract class JdbcDatabase implements Database<Connection> {
 	}
 
 	@Override
-	public void updateExpiryTimeAndEta(Connection txn, ContactId c, MessageId m,
-			long maxLatency) throws DbException {
+	public void updateRetransmissionData(Connection txn, ContactId c,
+			MessageId m, long maxLatency) throws DbException {
 		PreparedStatement ps = null;
 		ResultSet rs = null;
 		try {
@@ -3660,13 +3663,12 @@ abstract class JdbcDatabase implements Database<Connection> {
 			rs.close();
 			ps.close();
 			sql = "UPDATE statuses"
-					+ " SET expiry = ?, txCount = txCount + 1, eta = ?"
+					+ " SET expiry = ?, txCount = txCount + 1, maxLatency = ?"
 					+ " WHERE messageId = ? AND contactId = ?";
 			ps = txn.prepareStatement(sql);
 			long now = clock.currentTimeMillis();
-			long eta = now + maxLatency;
 			ps.setLong(1, calculateExpiry(now, maxLatency, txCount));
-			ps.setLong(2, eta);
+			ps.setLong(2, maxLatency);
 			ps.setBytes(3, m.getBytes());
 			ps.setInt(4, c.getInt());
 			int affected = ps.executeUpdate();

bramble-core/src/main/java/org/briarproject/bramble/db/Migration49_50.java

@@ -0,0 +1,45 @@
+package org.briarproject.bramble.db;
+
+import org.briarproject.bramble.api.db.DbException;
+
+import java.sql.Connection;
+import java.sql.SQLException;
+import java.sql.Statement;
+import java.util.logging.Logger;
+
+import static java.util.logging.Level.WARNING;
+import static java.util.logging.Logger.getLogger;
+import static org.briarproject.bramble.db.JdbcUtils.tryToClose;
+
+class Migration49_50 implements Migration<Connection> {
+
+	private static final Logger LOG = getLogger(Migration49_50.class.getName());
+
+	@Override
+	public int getStartVersion() {
+		return 49;
+	}
+
+	@Override
+	public int getEndVersion() {
+		return 50;
+	}
+
+	@Override
+	public void migrate(Connection txn) throws DbException {
+		Statement s = null;
+		try {
+			s = txn.createStatement();
+			s.execute("ALTER TABLE statuses"
+					+ " ALTER COLUMN eta"
+					+ " RENAME TO maxLatency");
+			s.execute("ALTER TABLE statuses"
+					+ " ALTER COLUMN maxLatency"
+					+ " SET NULL");
+			s.execute("UPDATE statuses SET maxLatency = NULL");
+		} catch (SQLException e) {
+			tryToClose(s, LOG, WARNING);
+			throw new DbException(e);
+		}
+	}
+}