db migration: fix #1844 and add additional assertions (#1889)

* db migration: fix #1844 and add additional assertions

- Migration scripts will now check to see if there are any unconverted
  snapshot IDs and fail the migration if there are any. This should
  prevent people from getting a corrupt database in the event the root
  cause is still unknown.
- Add an ORDER BY clause when doing batch queries in the postgres
  migration. LIMIT and OFFSET without ORDER BY are undefined and must
  not be relied upon to produce a deterministic ordering (e.g row order).
  See https://www.postgresql.org/docs/current/queries-limit.html

* Linting

Co-authored-by: Neil Alexander <neilalexander@users.noreply.github.com>
This commit is contained in:
kegsay 2021-06-29 11:25:17 +01:00 committed by GitHub
parent e2b6a90d90
commit c849e74dfc
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
2 changed files with 45 additions and 3 deletions

View File

@ -119,11 +119,15 @@ func UpStateBlocksRefactor(tx *sql.Tx) error {
_roomserver_state_snapshots
JOIN _roomserver_state_block ON _roomserver_state_block.state_block_nid = ANY (_roomserver_state_snapshots.state_block_nids)
WHERE
_roomserver_state_snapshots.state_snapshot_nid = ANY ( SELECT DISTINCT
_roomserver_state_snapshots.state_snapshot_nid = ANY (
SELECT
_roomserver_state_snapshots.state_snapshot_nid
FROM
_roomserver_state_snapshots
LIMIT $1 OFFSET $2)) AS _roomserver_state_block
ORDER BY _roomserver_state_snapshots.state_snapshot_nid ASC
LIMIT $1 OFFSET $2
)
) AS _roomserver_state_block
GROUP BY
state_snapshot_nid,
room_nid,
@ -202,6 +206,23 @@ func UpStateBlocksRefactor(tx *sql.Tx) error {
}
}
// By this point we should have no more state_snapshot_nids below maxsnapshotid in either roomserver_rooms or roomserver_events
// If we do, this is a problem if Dendrite tries to load the snapshot as it will not exist
// in roomserver_state_snapshots
var count int64
if err = tx.QueryRow(`SELECT COUNT(*) FROM roomserver_events WHERE state_snapshot_nid < $1 AND state_snapshot_nid != 0`, maxsnapshotid).Scan(&count); err != nil {
return fmt.Errorf("assertion query failed: %s", err)
}
if count > 0 {
return fmt.Errorf("%d events exist in roomserver_events which have not been converted to a new state_snapshot_nid; this is a bug, please report", count)
}
if err = tx.QueryRow(`SELECT COUNT(*) FROM roomserver_rooms WHERE state_snapshot_nid < $1 AND state_snapshot_nid != 0`, maxsnapshotid).Scan(&count); err != nil {
return fmt.Errorf("assertion query failed: %s", err)
}
if count > 0 {
return fmt.Errorf("%d rooms exist in roomserver_rooms which have not been converted to a new state_snapshot_nid; this is a bug, please report", count)
}
if _, err = tx.Exec(`
DROP TABLE _roomserver_state_snapshots;
DROP SEQUENCE roomserver_state_snapshot_nid_seq;

View File

@ -31,6 +31,7 @@ func LoadStateBlocksRefactor(m *sqlutil.Migrations) {
m.AddMigration(UpStateBlocksRefactor, DownStateBlocksRefactor)
}
// nolint:gocyclo
func UpStateBlocksRefactor(tx *sql.Tx) error {
logrus.Warn("Performing state storage upgrade. Please wait, this may take some time!")
defer logrus.Warn("State storage upgrade complete")
@ -45,6 +46,7 @@ func UpStateBlocksRefactor(tx *sql.Tx) error {
}
maxsnapshotid++
maxblockid++
oldMaxSnapshotID := maxsnapshotid
if _, err := tx.Exec(`ALTER TABLE roomserver_state_block RENAME TO _roomserver_state_block;`); err != nil {
return fmt.Errorf("tx.Exec: %w", err)
@ -133,6 +135,7 @@ func UpStateBlocksRefactor(tx *sql.Tx) error {
if jerr != nil {
return fmt.Errorf("json.Marshal (new blocks): %w", jerr)
}
var newsnapshot types.StateSnapshotNID
err = tx.QueryRow(`
INSERT INTO roomserver_state_snapshots (state_snapshot_nid, state_snapshot_hash, room_nid, state_block_nids)
@ -144,7 +147,8 @@ func UpStateBlocksRefactor(tx *sql.Tx) error {
return fmt.Errorf("tx.QueryRow.Scan (insert new snapshot): %w", err)
}
maxsnapshotid++
if _, err = tx.Exec(`UPDATE roomserver_events SET state_snapshot_nid=$1 WHERE state_snapshot_nid=$2 AND state_snapshot_nid<$3`, newsnapshot, snapshot, maxsnapshotid); err != nil {
_, err = tx.Exec(`UPDATE roomserver_events SET state_snapshot_nid=$1 WHERE state_snapshot_nid=$2 AND state_snapshot_nid<$3`, newsnapshot, snapshot, maxsnapshotid)
if err != nil {
return fmt.Errorf("tx.Exec (update events): %w", err)
}
if _, err = tx.Exec(`UPDATE roomserver_rooms SET state_snapshot_nid=$1 WHERE state_snapshot_nid=$2 AND state_snapshot_nid<$3`, newsnapshot, snapshot, maxsnapshotid); err != nil {
@ -153,6 +157,23 @@ func UpStateBlocksRefactor(tx *sql.Tx) error {
}
}
// By this point we should have no more state_snapshot_nids below oldMaxSnapshotID in either roomserver_rooms or roomserver_events
// If we do, this is a problem if Dendrite tries to load the snapshot as it will not exist
// in roomserver_state_snapshots
var count int64
if err = tx.QueryRow(`SELECT COUNT(*) FROM roomserver_events WHERE state_snapshot_nid < $1 AND state_snapshot_nid != 0`, oldMaxSnapshotID).Scan(&count); err != nil {
return fmt.Errorf("assertion query failed: %s", err)
}
if count > 0 {
return fmt.Errorf("%d events exist in roomserver_events which have not been converted to a new state_snapshot_nid; this is a bug, please report", count)
}
if err = tx.QueryRow(`SELECT COUNT(*) FROM roomserver_rooms WHERE state_snapshot_nid < $1 AND state_snapshot_nid != 0`, oldMaxSnapshotID).Scan(&count); err != nil {
return fmt.Errorf("assertion query failed: %s", err)
}
if count > 0 {
return fmt.Errorf("%d rooms exist in roomserver_rooms which have not been converted to a new state_snapshot_nid; this is a bug, please report", count)
}
if _, err = tx.Exec(`DROP TABLE _roomserver_state_snapshots;`); err != nil {
return fmt.Errorf("tx.Exec (delete old snapshot table): %w", err)
}