Improve tap-to-view deletion query

ts/services/tapToViewMessagesDeletionService.ts

@@ -6,6 +6,7 @@ import { DataReader } from '../sql/Client';
 import { clearTimeoutIfNecessary } from '../util/clearTimeoutIfNecessary';
 import { getMessageQueueTime } from '../util/getMessageQueueTime';
 import * as Errors from '../types/errors';
+import { strictAssert } from '../util/assert';
 
 async function eraseTapToViewMessages() {
   try {
@@ -15,8 +16,15 @@ async function eraseTapToViewMessages() {
     const maxTimestamp = Date.now() - getMessageQueueTime();
     const messages =
       await DataReader.getTapToViewMessagesNeedingErase(maxTimestamp);
+
     await Promise.all(
       messages.map(async fromDB => {
+        strictAssert(fromDB.isViewOnce === true, 'Must be view once');
+        strictAssert(
+          (fromDB.received_at_ms ?? 0) <= maxTimestamp,
+          'Must be older than maxTimestamp'
+        );
+
         const message = window.MessageCache.__DEPRECATED$register(
           fromDB.id,
           fromDB,
@@ -55,13 +63,14 @@ class TapToViewMessagesDeletionService {
   }
 
   private async checkTapToViewMessages() {
-    const receivedAt =
+    const receivedAtMsForOldestTapToViewMessage =
       await DataReader.getNextTapToViewMessageTimestampToAgeOut();
-    if (!receivedAt) {
+    if (!receivedAtMsForOldestTapToViewMessage) {
       return;
     }
 
-    const nextCheck = receivedAt + getMessageQueueTime();
+    const nextCheck =
+      receivedAtMsForOldestTapToViewMessage + getMessageQueueTime();
     window.SignalContext.log.info(
       'checkTapToViewMessages: next check at',
       new Date(nextCheck).toISOString()

ts/sql/Server.ts

@@ -4584,7 +4584,8 @@ function getNextTapToViewMessageTimestampToAgeOut(
       `
       SELECT json FROM messages
       WHERE
-        isViewOnce = 1
+        -- we want this query to use the messages_view_once index rather than received_at
+        likelihood(isViewOnce = 1, 0.01)
         AND (isErased IS NULL OR isErased != 1)
       ORDER BY received_at ASC, sent_at ASC
       LIMIT 1;
@@ -4595,9 +4596,8 @@ function getNextTapToViewMessageTimestampToAgeOut(
   if (!row) {
     return undefined;
   }
-
   const data = jsonToObject<MessageType>(row.json);
-  const result = data.received_at_ms || data.received_at;
+  const result = data.received_at_ms;
   return isNormalNumber(result) ? result : undefined;
 }
 
@@ -4613,8 +4613,9 @@ function getTapToViewMessagesNeedingErase(
       WHERE
         isViewOnce = 1
         AND (isErased IS NULL OR isErased != 1)
-        AND received_at <= $maxTimestamp
-      ORDER BY received_at ASC, sent_at ASC;
+        AND (
+          IFNULL(json ->> '$.received_at_ms', 0) <= $maxTimestamp
+        )
       `
     )
     .all({