CBG-4928: Update log messages on changes feed being cancelled (#7880)

Co-authored-by: Tor Colvin <tor.colvin@couchbase.com>

Author: RIT3shSapata

db/blip_handler.go

@@ -629,7 +629,7 @@ func (bh *blipHandler) sendBatchOfChanges(sender *blip.Sender, changeArray [][]a
 		bh.replicationStats.SendChangesCount.Add(int64(len(changeArray)))
 		// Spawn a goroutine to await the client's response:
 		go func(bh *blipHandler, sender *blip.Sender, response *blip.Message, changeArray [][]any, sendTime time.Time, dbCollection *DatabaseCollectionWithUser) {
-			if err := bh.handleChangesResponse(bh.loggingCtx, sender, response, changeArray, sendTime, dbCollection, bh.collectionIdx); err != nil {
+			if err := bh.handleChangesResponse(bh.loggingCtx, sender, response, changeArray, sendTime, dbCollection, bh.collectionIdx); err != nil && !errors.Is(err, ErrClosedBLIPSender) {
 				base.WarnfCtx(bh.loggingCtx, "Error from bh.handleChangesResponse: %v", err)
 				if bh.fatalErrorCallback != nil {
 					bh.fatalErrorCallback(err)

db/changes.go

@@ -996,7 +996,9 @@ func (col *DatabaseCollectionWithUser) SimpleMultiChangesFeed(ctx context.Contex
 						} else {
 							// On feed error, send the error and exit changes processing
 							if current[i].Err == base.ErrChannelFeed {
-								base.WarnfCtx(ctx, "MultiChangesFeed got error reading changes feed: %v", current[i].Err)
+								if options.ChangesCtx.Err() == nil {
+									base.WarnfCtx(ctx, "MultiChangesFeed got error reading changes feed: %v", current[i].Err)
+								}
 								select {
 								case <-options.ChangesCtx.Done():
 								case output <- current[i]:

db/channel_cache_single.go

@@ -410,10 +410,9 @@ func (c *singleChannelCacheImpl) GetChanges(ctx context.Context, options Changes
 		return resultFromCache, nil
 	}
 
-	// Check whether the changes process has been terminated while we waited for the view lock, to avoid the view
-	// overhead in that case (and prevent feedback loop on query backlog)
+	// Check whether the changes process has been terminated before running a query
 	if options.ChangesCtx.Err() != nil {
-		return nil, fmt.Errorf("Changes feed cancelled while waiting for view lock")
+		return nil, fmt.Errorf("Changes feed cancelled %w", options.ChangesCtx.Err())
 	}
 
 	// Now query the view. We set the max sequence equal to cacheValidFrom, so we'll get one