Migrate ChannelStore.UpdateLastViewedAt to squirrel (#19439)

Fixes https://github.com/mattermost/mattermost-server/issues/19332

```release-note
NONE
```

Co-authored-by: Mattermod <mattermod@users.noreply.github.com>

store/sqlstore/channel_store.go

@@ -2431,7 +2431,6 @@ func (s SqlChannelStore) PermanentDeleteMembersByUser(userId string) error {
 	return nil
 }
 
-// TODO: convert to squirrel (https://github.com/mattermost/mattermost-server/issues/19332)
 func (s SqlChannelStore) UpdateLastViewedAt(channelIds []string, userId string, updateThreads bool) (map[string]int64, error) {
 	var threadsToUpdate []string
 	now := model.GetMillis()
@@ -2443,38 +2442,50 @@ func (s SqlChannelStore) UpdateLastViewedAt(channelIds []string, userId string,
 		}
 	}
 
-	keys, props := MapStringsToQueryParams(channelIds, "Channel")
+	lastPostAtTimes := []struct {
-	props["UserId"] = userId
-
-	var lastPostAtTimes []struct {
 		Id                string
 		LastPostAt        int64
 		TotalMsgCount     int64
 		TotalMsgCountRoot int64
-	}
+	}{}
+
+	// We use the question placeholder format for both databases, because
+	// we replace that with the dollar format later on.
+	// It's needed to support the prefix CTE query. See: https://github.com/Masterminds/squirrel/issues/285.
+	query := sq.StatementBuilder.PlaceholderFormat(sq.Question).
+		Select("Id, LastPostAt, TotalMsgCount, TotalMsgCountRoot").
+		From("Channels").
+		Where(sq.Eq{"Id": channelIds})
 
-	query := `SELECT Id, LastPostAt, TotalMsgCount, TotalMsgCountRoot FROM Channels WHERE Id IN ` + keys
 	// TODO: use a CTE for mysql too when version 8 becomes the minimum supported version.
 	if s.DriverName() == model.DatabaseDriverPostgres {
-		query = `WITH c AS ( ` + query + `),
+		with := query.Prefix("WITH c AS (").Suffix(") ,")
-	updated AS (
+		update := sq.StatementBuilder.PlaceholderFormat(sq.Question).
-	UPDATE
+			Update("ChannelMembers cm").
-		ChannelMembers cm
+			Set("MentionCount", 0).
-	SET
+			Set("MentionCountRoot", 0).
-		MentionCount = 0,
+			Set("MsgCount", sq.Expr("greatest(cm.MsgCount, c.TotalMsgCount)")).
-		MentionCountRoot = 0,
+			Set("MsgCountRoot", sq.Expr("greatest(cm.MsgCountRoot, c.TotalMsgCountRoot)")).
-		MsgCount = greatest(cm.MsgCount, c.TotalMsgCount),
+			Set("LastViewedAt", sq.Expr("greatest(cm.LastViewedAt, c.LastPostAt)")).
-		MsgCountRoot = greatest(cm.MsgCountRoot, c.TotalMsgCountRoot),
+			Set("LastUpdateAt", sq.Expr("greatest(cm.LastViewedAt, c.LastPostAt)")).
-		LastViewedAt = greatest(cm.LastViewedAt, c.LastPostAt),
+			SuffixExpr(sq.Expr("FROM c WHERE cm.UserId = ? AND c.Id = cm.ChannelId", userId))
-		LastUpdateAt = greatest(cm.LastViewedAt, c.LastPostAt)
+		updateWrap := update.Prefix("updated AS (").Suffix(")")
-	FROM c
+		query = with.SuffixExpr(updateWrap).Suffix("SELECT Id, LastPostAt FROM c")
-		WHERE cm.UserId = :UserId
-		AND c.Id=cm.ChannelId
-)
-	SELECT Id, LastPostAt FROM c`
 	}
 
-	_, err := s.GetMaster().Select(&lastPostAtTimes, query, props)
+	sql, args, err := query.ToSql()
+	if err != nil {
+		return nil, errors.Wrap(err, "UpdateLastViewedAt_CTE_Tosql")
+	}
+
+	if s.DriverName() == model.DatabaseDriverPostgres {
+		sql, err = sq.Dollar.ReplacePlaceholders(sql)
+		if err != nil {
+			return nil, errors.Wrap(err, "UpdateLastViewedAt_ReplacePlaceholders")
+		}
+	}
+
+	err = s.GetMasterX().Select(&lastPostAtTimes, sql, args...)
 	if err != nil {
 		return nil, errors.Wrapf(err, "failed to find ChannelMembers data with userId=%s and channelId in %v", userId, channelIds)
 	}
@@ -2494,39 +2505,42 @@ func (s SqlChannelStore) UpdateLastViewedAt(channelIds []string, userId string,
 		return times, nil
 	}
 
-	msgCountQuery := ""
+	var msgCountQuery, msgCountQueryRoot, lastViewedQuery = sq.Case("ChannelId"), sq.Case("ChannelId"), sq.Case("ChannelId")
-	msgCountQueryRoot := ""
-	lastViewedQuery := ""
 
-	for index, t := range lastPostAtTimes {
+	for _, t := range lastPostAtTimes {
 		times[t.Id] = t.LastPostAt
 
-		props["msgCount"+strconv.Itoa(index)] = t.TotalMsgCount
+		msgCountQuery = msgCountQuery.When(
-		msgCountQuery += fmt.Sprintf("WHEN :channelId%d THEN GREATEST(MsgCount, :msgCount%d) ", index, index)
+			sq.Expr("?", t.Id),
+			sq.Expr("GREATEST(MsgCount, ?)", t.TotalMsgCount))
 
-		props["msgCountRoot"+strconv.Itoa(index)] = t.TotalMsgCountRoot
+		msgCountQueryRoot = msgCountQueryRoot.When(
-		msgCountQueryRoot += fmt.Sprintf("WHEN :channelId%d THEN GREATEST(MsgCountRoot, :msgCountRoot%d) ", index, index)
+			sq.Expr("?", t.Id),
+			sq.Expr("GREATEST(MsgCountRoot, ?)", t.TotalMsgCountRoot))
 
-		props["lastViewed"+strconv.Itoa(index)] = t.LastPostAt
+		lastViewedQuery = lastViewedQuery.When(
-		lastViewedQuery += fmt.Sprintf("WHEN :channelId%d THEN GREATEST(LastViewedAt, :lastViewed%d) ", index, index)
+			sq.Expr("?", t.Id),
-
+			sq.Expr("GREATEST(LastViewedAt, ?)", t.LastPostAt))
-		props["channelId"+strconv.Itoa(index)] = t.Id
 	}
 
-	updateQuery := `UPDATE
+	updateQuery := s.getQueryBuilder().Update("ChannelMembers").
-			ChannelMembers
+		Set("MentionCount", 0).
-		SET
+		Set("MentionCountRoot", 0).
-			MentionCount = 0,
+		Set("MsgCount", msgCountQuery).
-			MentionCountRoot = 0,
+		Set("MsgCountRoot", msgCountQueryRoot).
-			MsgCount = CASE ChannelId ` + msgCountQuery + ` END,
+		Set("LastViewedAt", lastViewedQuery).
-			MsgCountRoot = CASE ChannelId ` + msgCountQueryRoot + ` END,
+		Set("LastUpdateAt", sq.Expr("LastViewedAt")).
-			LastViewedAt = CASE ChannelId ` + lastViewedQuery + ` END,
+		Where(sq.Eq{
-			LastUpdateAt = LastViewedAt
+			"UserId":    userId,
-		WHERE
+			"ChannelId": channelIds,
-				UserId = :UserId
+		})
-				AND ChannelId IN ` + keys
 
-	if _, err := s.GetMaster().Exec(updateQuery, props); err != nil {
+	sql, args, err = updateQuery.ToSql()
+	if err != nil {
+		return nil, errors.Wrap(err, "UpdateLastViewedAt_Update_Tosql")
+	}
+
+	if _, err := s.GetMasterX().Exec(sql, args...); err != nil {
 		return nil, errors.Wrapf(err, "failed to update ChannelMembers with userId=%s and channelId in %v", userId, channelIds)
 	}