Merge Updater structs (#1069)

* Move Updater structs to shared and use it for postgres

* Add constructors for NewXXXUpdater and a useTxns flag

In sqlite, we set useTxns=false and comment why.

* Handle nil txn

* Handle nil in transaction

* Missed one

* Close the txn at the right time

* Don't close the transaction as we reuse it between calls
This commit is contained in:
Kegsay 2020-05-28 11:15:21 +01:00 committed by GitHub
parent 02fe38e1f7
commit a6f995eb45
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
8 changed files with 381 additions and 744 deletions

View file

@ -90,7 +90,6 @@ func (s *inviteStatements) InsertInviteEvent(
inviteEventJSON []byte,
) (bool, error) {
stmt := internal.TxStmt(txn, s.insertInviteEventStmt)
defer stmt.Close() // nolint: errcheck
result, err := stmt.ExecContext(
ctx, inviteEventID, roomNID, targetUserNID, senderUserNID, inviteEventJSON,
)
@ -109,7 +108,7 @@ func (s *inviteStatements) UpdateInviteRetired(
txn *sql.Tx, roomNID types.RoomNID, targetUserNID types.EventStateKeyNID,
) (eventIDs []string, err error) {
// gather all the event IDs we will retire
stmt := txn.Stmt(s.selectInvitesAboutToRetireStmt)
stmt := internal.TxStmt(txn, s.selectInvitesAboutToRetireStmt)
rows, err := stmt.QueryContext(ctx, roomNID, targetUserNID)
if err != nil {
return nil, err
@ -124,7 +123,7 @@ func (s *inviteStatements) UpdateInviteRetired(
}
// now retire the invites
stmt = txn.Stmt(s.updateInviteRetiredStmt)
stmt = internal.TxStmt(txn, s.updateInviteRetiredStmt)
_, err = stmt.ExecContext(ctx, roomNID, targetUserNID)
return
}

View file

@ -140,387 +140,27 @@ func Open(dataSourceName string) (*Database, error) {
return &d, nil
}
func (d *Database) assignRoomNID(
ctx context.Context, txn *sql.Tx,
roomID string, roomVersion gomatrixserverlib.RoomVersion,
) (roomNID types.RoomNID, err error) {
// Check if we already have a numeric ID in the database.
roomNID, err = d.rooms.SelectRoomNID(ctx, txn, roomID)
if err == sql.ErrNoRows {
// We don't have a numeric ID so insert one into the database.
roomNID, err = d.rooms.InsertRoomNID(ctx, txn, roomID, roomVersion)
if err == nil {
// Now get the numeric ID back out of the database
roomNID, err = d.rooms.SelectRoomNID(ctx, txn, roomID)
}
}
return
}
func (d *Database) assignStateKeyNID(
ctx context.Context, txn *sql.Tx, eventStateKey string,
) (eventStateKeyNID types.EventStateKeyNID, err error) {
// Check if we already have a numeric ID in the database.
eventStateKeyNID, err = d.eventStateKeys.SelectEventStateKeyNID(ctx, txn, eventStateKey)
if err == sql.ErrNoRows {
// We don't have a numeric ID so insert one into the database.
eventStateKeyNID, err = d.eventStateKeys.InsertEventStateKeyNID(ctx, txn, eventStateKey)
if err == sql.ErrNoRows {
// We raced with another insert so run the select again.
eventStateKeyNID, err = d.eventStateKeys.SelectEventStateKeyNID(ctx, txn, eventStateKey)
}
}
return
}
// GetLatestEventsForUpdate implements input.EventDatabase
func (d *Database) GetLatestEventsForUpdate(
ctx context.Context, roomNID types.RoomNID,
) (types.RoomRecentEventsUpdater, error) {
txn, err := d.db.Begin()
if err != nil {
return nil, err
}
eventNIDs, lastEventNIDSent, currentStateSnapshotNID, err :=
d.rooms.SelectLatestEventsNIDsForUpdate(ctx, txn, roomNID)
if err != nil {
txn.Rollback() // nolint: errcheck
return nil, err
}
stateAndRefs, err := d.events.BulkSelectStateAtEventAndReference(ctx, txn, eventNIDs)
if err != nil {
txn.Rollback() // nolint: errcheck
return nil, err
}
var lastEventIDSent string
if lastEventNIDSent != 0 {
lastEventIDSent, err = d.events.SelectEventID(ctx, txn, lastEventNIDSent)
if err != nil {
txn.Rollback() // nolint: errcheck
return nil, err
}
}
// FIXME: we probably want to support long-lived txns in sqlite somehow, but we don't because we get
// 'database is locked' errors caused by multiple write txns (one being the long-lived txn created here)
// so for now let's not use a long-lived txn at all, and just commit it here and set the txn to nil so
// we fail fast if someone tries to use the underlying txn object.
err = txn.Commit()
if err != nil {
return nil, err
}
return &roomRecentEventsUpdater{
transaction{ctx, nil}, d, roomNID, stateAndRefs, lastEventIDSent, currentStateSnapshotNID,
}, nil
// TODO: Do not use transactions. We should be holding open this transaction but we cannot have
// multiple write transactions on sqlite. The code will perform additional
// write transactions independent of this one which will consistently cause
// 'database is locked' errors. As sqlite doesn't support multi-process on the
// same DB anyway, and we only execute updates sequentially, the only worries
// are for rolling back when things go wrong. (atomicity)
return shared.NewRoomRecentEventsUpdater(&d.Database, ctx, roomNID, false)
}
type roomRecentEventsUpdater struct {
transaction
d *Database
roomNID types.RoomNID
latestEvents []types.StateAtEventAndReference
lastEventIDSent string
currentStateSnapshotNID types.StateSnapshotNID
}
// RoomVersion implements types.RoomRecentEventsUpdater
func (u *roomRecentEventsUpdater) RoomVersion() (version gomatrixserverlib.RoomVersion) {
version, _ = u.d.GetRoomVersionForRoomNID(u.ctx, u.roomNID)
return
}
// LatestEvents implements types.RoomRecentEventsUpdater
func (u *roomRecentEventsUpdater) LatestEvents() []types.StateAtEventAndReference {
return u.latestEvents
}
// LastEventIDSent implements types.RoomRecentEventsUpdater
func (u *roomRecentEventsUpdater) LastEventIDSent() string {
return u.lastEventIDSent
}
// CurrentStateSnapshotNID implements types.RoomRecentEventsUpdater
func (u *roomRecentEventsUpdater) CurrentStateSnapshotNID() types.StateSnapshotNID {
return u.currentStateSnapshotNID
}
// StorePreviousEvents implements types.RoomRecentEventsUpdater
func (u *roomRecentEventsUpdater) StorePreviousEvents(eventNID types.EventNID, previousEventReferences []gomatrixserverlib.EventReference) error {
err := internal.WithTransaction(u.d.db, func(txn *sql.Tx) error {
for _, ref := range previousEventReferences {
if err := u.d.prevEvents.InsertPreviousEvent(u.ctx, txn, ref.EventID, ref.EventSHA256, eventNID); err != nil {
return err
}
}
return nil
})
return err
}
// IsReferenced implements types.RoomRecentEventsUpdater
func (u *roomRecentEventsUpdater) IsReferenced(eventReference gomatrixserverlib.EventReference) (res bool, err error) {
err = internal.WithTransaction(u.d.db, func(txn *sql.Tx) error {
err := u.d.prevEvents.SelectPreviousEventExists(u.ctx, txn, eventReference.EventID, eventReference.EventSHA256)
if err == nil {
res = true
err = nil
}
if err == sql.ErrNoRows {
res = false
err = nil
}
return err
})
return
}
// SetLatestEvents implements types.RoomRecentEventsUpdater
func (u *roomRecentEventsUpdater) SetLatestEvents(
roomNID types.RoomNID, latest []types.StateAtEventAndReference, lastEventNIDSent types.EventNID,
currentStateSnapshotNID types.StateSnapshotNID,
) error {
err := internal.WithTransaction(u.d.db, func(txn *sql.Tx) error {
eventNIDs := make([]types.EventNID, len(latest))
for i := range latest {
eventNIDs[i] = latest[i].EventNID
}
return u.d.rooms.UpdateLatestEventNIDs(u.ctx, txn, roomNID, eventNIDs, lastEventNIDSent, currentStateSnapshotNID)
})
return err
}
// HasEventBeenSent implements types.RoomRecentEventsUpdater
func (u *roomRecentEventsUpdater) HasEventBeenSent(eventNID types.EventNID) (res bool, err error) {
err = internal.WithTransaction(u.d.db, func(txn *sql.Tx) error {
res, err = u.d.events.SelectEventSentToOutput(u.ctx, txn, eventNID)
return err
})
return
}
// MarkEventAsSent implements types.RoomRecentEventsUpdater
func (u *roomRecentEventsUpdater) MarkEventAsSent(eventNID types.EventNID) error {
err := internal.WithTransaction(u.d.db, func(txn *sql.Tx) error {
return u.d.events.UpdateEventSentToOutput(u.ctx, txn, eventNID)
})
return err
}
func (u *roomRecentEventsUpdater) MembershipUpdater(targetUserNID types.EventStateKeyNID, targetLocal bool) (mu types.MembershipUpdater, err error) {
err = internal.WithTransaction(u.d.db, func(txn *sql.Tx) error {
mu, err = u.d.membershipUpdaterTxn(u.ctx, txn, u.roomNID, targetUserNID, targetLocal)
return err
})
return
}
// MembershipUpdater implements input.RoomEventDatabase
func (d *Database) MembershipUpdater(
ctx context.Context, roomID, targetUserID string,
targetLocal bool, roomVersion gomatrixserverlib.RoomVersion,
) (updater types.MembershipUpdater, err error) {
var txn *sql.Tx
txn, err = d.db.Begin()
if err != nil {
return nil, err
}
succeeded := false
defer func() {
if !succeeded {
txn.Rollback() // nolint: errcheck
} else {
// TODO: We should be holding open this transaction but we cannot have
// multiple write transactions on sqlite. The code will perform additional
// write transactions independent of this one which will consistently cause
// 'database is locked' errors. For now, we'll break up the transaction and
// hope we don't race too catastrophically. Long term, we should be able to
// thread in txn objects where appropriate (either at the interface level or
// bring matrix business logic into the storage layer).
txerr := txn.Commit()
if err == nil && txerr != nil {
err = txerr
}
}
}()
roomNID, err := d.assignRoomNID(ctx, txn, roomID, roomVersion)
if err != nil {
return nil, err
}
targetUserNID, err := d.assignStateKeyNID(ctx, txn, targetUserID)
if err != nil {
return nil, err
}
updater, err = d.membershipUpdaterTxn(ctx, txn, roomNID, targetUserNID, targetLocal)
if err != nil {
return nil, err
}
succeeded = true
return updater, nil
}
type membershipUpdater struct {
transaction
d *Database
roomNID types.RoomNID
targetUserNID types.EventStateKeyNID
membership tables.MembershipState
}
func (d *Database) membershipUpdaterTxn(
ctx context.Context,
txn *sql.Tx,
roomNID types.RoomNID,
targetUserNID types.EventStateKeyNID,
targetLocal bool,
) (types.MembershipUpdater, error) {
if err := d.membership.InsertMembership(ctx, txn, roomNID, targetUserNID, targetLocal); err != nil {
return nil, err
}
membership, err := d.membership.SelectMembershipForUpdate(ctx, txn, roomNID, targetUserNID)
if err != nil {
return nil, err
}
return &membershipUpdater{
// purposefully set the txn to nil so if we try to use it we panic and fail fast
transaction{ctx, nil}, d, roomNID, targetUserNID, membership,
}, nil
}
// IsInvite implements types.MembershipUpdater
func (u *membershipUpdater) IsInvite() bool {
return u.membership == tables.MembershipStateInvite
}
// IsJoin implements types.MembershipUpdater
func (u *membershipUpdater) IsJoin() bool {
return u.membership == tables.MembershipStateJoin
}
// IsLeave implements types.MembershipUpdater
func (u *membershipUpdater) IsLeave() bool {
return u.membership == tables.MembershipStateLeaveOrBan
}
// SetToInvite implements types.MembershipUpdater
func (u *membershipUpdater) SetToInvite(event gomatrixserverlib.Event) (inserted bool, err error) {
err = internal.WithTransaction(u.d.db, func(txn *sql.Tx) error {
senderUserNID, err := u.d.assignStateKeyNID(u.ctx, txn, event.Sender())
if err != nil {
return err
}
inserted, err = u.d.invites.InsertInviteEvent(
u.ctx, txn, event.EventID(), u.roomNID, u.targetUserNID, senderUserNID, event.JSON(),
)
if err != nil {
return err
}
if u.membership != tables.MembershipStateInvite {
if err = u.d.membership.UpdateMembership(
u.ctx, txn, u.roomNID, u.targetUserNID, senderUserNID, tables.MembershipStateInvite, 0,
); err != nil {
return err
}
}
return nil
})
return
}
// SetToJoin implements types.MembershipUpdater
func (u *membershipUpdater) SetToJoin(senderUserID string, eventID string, isUpdate bool) (inviteEventIDs []string, err error) {
err = internal.WithTransaction(u.d.db, func(txn *sql.Tx) error {
senderUserNID, err := u.d.assignStateKeyNID(u.ctx, txn, senderUserID)
if err != nil {
return err
}
// If this is a join event update, there is no invite to update
if !isUpdate {
inviteEventIDs, err = u.d.invites.UpdateInviteRetired(
u.ctx, txn, u.roomNID, u.targetUserNID,
)
if err != nil {
return err
}
}
// Look up the NID of the new join event
nIDs, err := u.d.EventNIDs(u.ctx, []string{eventID})
if err != nil {
return err
}
if u.membership != tables.MembershipStateJoin || isUpdate {
if err = u.d.membership.UpdateMembership(
u.ctx, txn, u.roomNID, u.targetUserNID, senderUserNID,
tables.MembershipStateJoin, nIDs[eventID],
); err != nil {
return err
}
}
return nil
})
return
}
// SetToLeave implements types.MembershipUpdater
func (u *membershipUpdater) SetToLeave(senderUserID string, eventID string) (inviteEventIDs []string, err error) {
err = internal.WithTransaction(u.d.db, func(txn *sql.Tx) error {
senderUserNID, err := u.d.assignStateKeyNID(u.ctx, txn, senderUserID)
if err != nil {
return err
}
inviteEventIDs, err = u.d.invites.UpdateInviteRetired(
u.ctx, txn, u.roomNID, u.targetUserNID,
)
if err != nil {
return err
}
// Look up the NID of the new leave event
nIDs, err := u.d.EventNIDs(u.ctx, []string{eventID})
if err != nil {
return err
}
if u.membership != tables.MembershipStateLeaveOrBan {
if err = u.d.membership.UpdateMembership(
u.ctx, txn, u.roomNID, u.targetUserNID, senderUserNID,
tables.MembershipStateLeaveOrBan, nIDs[eventID],
); err != nil {
return err
}
}
return nil
})
return
}
type transaction struct {
ctx context.Context
txn *sql.Tx
}
// Commit implements types.Transaction
func (t *transaction) Commit() error {
if t.txn == nil {
return nil
}
return t.txn.Commit()
}
// Rollback implements types.Transaction
func (t *transaction) Rollback() error {
if t.txn == nil {
return nil
}
return t.txn.Rollback()
// TODO: Do not use transactions. We should be holding open this transaction but we cannot have
// multiple write transactions on sqlite. The code will perform additional
// write transactions independent of this one which will consistently cause
// 'database is locked' errors. As sqlite doesn't support multi-process on the
// same DB anyway, and we only execute updates sequentially, the only worries
// are for rolling back when things go wrong. (atomicity)
return shared.NewMembershipUpdater(ctx, &d.Database, roomID, targetUserID, targetLocal, roomVersion, false)
}