Add database functions for storing, retrieving and cleaning last hash for snodes

app/sql.js

@@ -102,8 +102,10 @@ module.exports = {
   getMessageCount,
   saveMessage,
   cleanSeenMessages,
+  cleanLastHashes,
   saveSeenMessageHashes,
   saveSeenMessageHash,
+  updateLastHash,
   saveMessages,
   removeMessage,
   getUnreadByConversation,
@@ -114,6 +116,7 @@ module.exports = {
   getAllUnsentMessages,
   getMessagesBySentAt,
   getSeenMessagesByHashList,
+  getLastHashBySnode,
   getExpiredMessages,
   getOutgoingWithoutExpiresAt,
   getNextExpiringMessage,
@@ -421,6 +424,14 @@ async function updateToSchemaVersion6(currentVersion, instance) {
      ADD COLUMN friendRequestStatus INTEGER;`
   );
 
+  await instance.run(
+    `CREATE TABLE lastHashes(
+      snode STRING PRIMARY KEY,
+      hash STRING,
+      expiresAt INTEGER
+    );`
+  );
+
   await instance.run(
     `CREATE TABLE seenMessages(
       hash STRING PRIMARY KEY,
@@ -1556,6 +1567,27 @@ async function saveSeenMessageHashes(arrayOfHashes) {
   await promise;
 }
 
+async function updateLastHash(data) {
+  const { snode, hash, expiresAt } = data;
+
+  await db.run(
+    `INSERT OR REPLACE INTO lastHashes (
+      snode,
+      hash,
+      expiresAt
+    ) values (
+      $snode,
+      $hash,
+      $expiresAt
+    )`,
+    {
+      $snode: snode,
+      $hash: hash,
+      $expiresAt: expiresAt,
+    }
+  );
+}
+
 async function saveSeenMessageHash(data) {
   const { expiresAt, hash } = data;
   await db.run(
@@ -1573,6 +1605,12 @@ async function saveSeenMessageHash(data) {
   );
 }
 
+async function cleanLastHashes() {
+  await db.run('DELETE FROM lastHashes WHERE expiresAt <= $now;', {
+    $now: Date.now(),
+  });
+}
+
 async function cleanSeenMessages() {
   await db.run('DELETE FROM seenMessages WHERE expiresAt <= $now;', {
     $now: Date.now(),
@@ -1710,6 +1748,19 @@ async function getMessagesBySentAt(sentAt) {
   return map(rows, row => jsonToObject(row.json));
 }
 
+async function getLastHashBySnode(snode) {
+  const row = await db.get('SELECT * FROM lastHashes WHERE snode = $snode;', {
+    $snode: snode,
+  });
+
+
+  if (!row) {
+    return null;
+  }
+
+  return row.lastHash;
+}
+
 async function getSeenMessagesByHashList(hashes) {
   const rows = await db.all(
     `SELECT * FROM seenMessages WHERE hash IN ( ${hashes

js/background.js

@@ -501,13 +501,14 @@
     }
   });
 
-  function manageSeenMessages() {
+  function manageExpiringData() {
     window.Signal.Data.cleanSeenMessages();
-    setTimeout(manageSeenMessages, 1000 * 60 * 60);
+    window.Signal.Data.cleanLastHashes();
+    setTimeout(manageExpiringData, 1000 * 60 * 60);
   }
 
   async function start() {
-    manageSeenMessages();
+    manageExpiringData();
     window.dispatchEvent(new Event('storage_ready'));
 
     window.log.info('listening for registration events');

js/modules/data.js

@@ -130,7 +130,9 @@ module.exports = {
   getMessageCount,
   saveMessage,
   cleanSeenMessages,
+  cleanLastHashes,
   saveSeenMessageHash,
+  updateLastHash,
   saveSeenMessageHashes,
   saveLegacyMessage,
   saveMessages,
@@ -151,6 +153,7 @@ module.exports = {
   getNextExpiringMessage,
   getMessagesByConversation,
   getSeenMessagesByHashList,
+  getLastHashBySnode,
 
   getUnprocessedCount,
   getAllUnprocessed,
@@ -778,10 +781,18 @@ async function cleanSeenMessages() {
   await channels.cleanSeenMessages();
 }
 
+async function cleanLastHashes() {
+  await channels.cleanLastHashes();
+}
+
 async function saveSeenMessageHashes(data) {
   await channels.saveSeenMessageHashes(_cleanData(data));
 }
 
+async function updateLastHash(data) {
+  await channels.updateLastHash(_cleanData(data));
+}
+
 async function saveSeenMessageHash(data) {
   await channels.saveSeenMessageHash(_cleanData(data));
 }
@@ -909,6 +920,11 @@ async function getMessagesByConversation(
   return new MessageCollection(messages);
 }
 
+async function getLastHashBySnode(snode) {
+  const lastHash = await channels.getLastHashBySnode(snode);
+  return lastHash;
+}
+
 async function getSeenMessagesByHashList(hashes) {
   const seenMessages = await channels.getSeenMessagesByHashList(hashes);
   return seenMessages;