0
0
Fork 0
mirror of https://github.com/matrix-org/dendrite synced 2024-10-31 04:59:07 +01:00
dendrite/syncapi/storage/sqlite3/output_room_events_table.go
Neil Alexander 21f8881985
Add indexes that optimise selectStateInRangeSQL (#2764)
This gets rid of some expensive scans on `add_state_ids` and
`remove_state_ids`, turning them into much cheaper and faster index
scans instead.
2022-10-04 16:43:10 +01:00

673 lines
22 KiB
Go

// Copyright 2017-2018 New Vector Ltd
// Copyright 2019-2020 The Matrix.org Foundation C.I.C.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package sqlite3
import (
"context"
"database/sql"
"encoding/json"
"fmt"
"sort"
"strings"
"github.com/matrix-org/dendrite/internal"
"github.com/matrix-org/dendrite/roomserver/api"
"github.com/matrix-org/dendrite/syncapi/storage/sqlite3/deltas"
"github.com/matrix-org/dendrite/syncapi/storage/tables"
"github.com/matrix-org/dendrite/syncapi/types"
"github.com/matrix-org/dendrite/internal/sqlutil"
"github.com/matrix-org/gomatrixserverlib"
)
const outputRoomEventsSchema = `
-- Stores output room events received from the roomserver.
CREATE TABLE IF NOT EXISTS syncapi_output_room_events (
id INTEGER PRIMARY KEY AUTOINCREMENT,
event_id TEXT NOT NULL UNIQUE,
room_id TEXT NOT NULL,
headered_event_json TEXT NOT NULL,
type TEXT NOT NULL,
sender TEXT NOT NULL,
contains_url BOOL NOT NULL,
add_state_ids TEXT, -- JSON encoded string array
remove_state_ids TEXT, -- JSON encoded string array
session_id BIGINT,
transaction_id TEXT,
exclude_from_sync BOOL NOT NULL DEFAULT FALSE,
history_visibility SMALLINT NOT NULL DEFAULT 2 -- The history visibility before this event (1 - world_readable; 2 - shared; 3 - invited; 4 - joined)
);
CREATE INDEX IF NOT EXISTS syncapi_output_room_events_type_idx ON syncapi_output_room_events (type);
CREATE INDEX IF NOT EXISTS syncapi_output_room_events_sender_idx ON syncapi_output_room_events (sender);
CREATE INDEX IF NOT EXISTS syncapi_output_room_events_room_id_idx ON syncapi_output_room_events (room_id);
CREATE INDEX IF NOT EXISTS syncapi_output_room_events_exclude_from_sync_idx ON syncapi_output_room_events (exclude_from_sync);
CREATE INDEX IF NOT EXISTS syncapi_output_room_events_add_state_ids_idx ON syncapi_output_room_events ((add_state_ids IS NOT NULL));
CREATE INDEX IF NOT EXISTS syncapi_output_room_events_remove_state_ids_idx ON syncapi_output_room_events ((remove_state_ids IS NOT NULL));
`
const insertEventSQL = "" +
"INSERT INTO syncapi_output_room_events (" +
"id, room_id, event_id, headered_event_json, type, sender, contains_url, add_state_ids, remove_state_ids, session_id, transaction_id, exclude_from_sync, history_visibility" +
") VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9, $10, $11, $12, $13) " +
"ON CONFLICT (event_id) DO UPDATE SET exclude_from_sync = (excluded.exclude_from_sync AND $14)"
const selectEventsSQL = "" +
"SELECT event_id, id, headered_event_json, session_id, exclude_from_sync, transaction_id, history_visibility FROM syncapi_output_room_events WHERE event_id IN ($1)"
const selectRecentEventsSQL = "" +
"SELECT event_id, id, headered_event_json, session_id, exclude_from_sync, transaction_id, history_visibility FROM syncapi_output_room_events" +
" WHERE room_id = $1 AND id > $2 AND id <= $3"
// WHEN, ORDER BY and LIMIT are appended by prepareWithFilters
const selectRecentEventsForSyncSQL = "" +
"SELECT event_id, id, headered_event_json, session_id, exclude_from_sync, transaction_id, history_visibility FROM syncapi_output_room_events" +
" WHERE room_id = $1 AND id > $2 AND id <= $3 AND exclude_from_sync = FALSE"
// WHEN, ORDER BY and LIMIT are appended by prepareWithFilters
const selectEarlyEventsSQL = "" +
"SELECT event_id, id, headered_event_json, session_id, exclude_from_sync, transaction_id, history_visibility FROM syncapi_output_room_events" +
" WHERE room_id = $1 AND id > $2 AND id <= $3"
// WHEN, ORDER BY and LIMIT are appended by prepareWithFilters
const selectMaxEventIDSQL = "" +
"SELECT MAX(id) FROM syncapi_output_room_events"
const updateEventJSONSQL = "" +
"UPDATE syncapi_output_room_events SET headered_event_json=$1 WHERE event_id=$2"
const selectStateInRangeSQL = "" +
"SELECT event_id, id, headered_event_json, exclude_from_sync, add_state_ids, remove_state_ids, history_visibility" +
" FROM syncapi_output_room_events" +
" WHERE (id > $1 AND id <= $2)" +
" AND room_id IN ($3)" +
" AND ((add_state_ids IS NOT NULL AND add_state_ids != '') OR (remove_state_ids IS NOT NULL AND remove_state_ids != ''))"
// WHEN, ORDER BY and LIMIT are appended by prepareWithFilters
const deleteEventsForRoomSQL = "" +
"DELETE FROM syncapi_output_room_events WHERE room_id = $1"
const selectContextEventSQL = "" +
"SELECT id, headered_event_json, history_visibility FROM syncapi_output_room_events WHERE room_id = $1 AND event_id = $2"
const selectContextBeforeEventSQL = "" +
"SELECT headered_event_json, history_visibility FROM syncapi_output_room_events WHERE room_id = $1 AND id < $2"
// WHEN, ORDER BY and LIMIT are appended by prepareWithFilters
const selectContextAfterEventSQL = "" +
"SELECT id, headered_event_json, history_visibility FROM syncapi_output_room_events WHERE room_id = $1 AND id > $2"
// WHEN, ORDER BY and LIMIT are appended by prepareWithFilters
const selectSearchSQL = "SELECT id, event_id, headered_event_json FROM syncapi_output_room_events WHERE type IN ($1) AND id > $2 LIMIT $3 ORDER BY id ASC"
type outputRoomEventsStatements struct {
db *sql.DB
streamIDStatements *StreamIDStatements
insertEventStmt *sql.Stmt
selectMaxEventIDStmt *sql.Stmt
updateEventJSONStmt *sql.Stmt
deleteEventsForRoomStmt *sql.Stmt
selectContextEventStmt *sql.Stmt
selectContextBeforeEventStmt *sql.Stmt
selectContextAfterEventStmt *sql.Stmt
//selectSearchStmt *sql.Stmt - prepared at runtime
}
func NewSqliteEventsTable(db *sql.DB, streamID *StreamIDStatements) (tables.Events, error) {
s := &outputRoomEventsStatements{
db: db,
streamIDStatements: streamID,
}
_, err := db.Exec(outputRoomEventsSchema)
if err != nil {
return nil, err
}
m := sqlutil.NewMigrator(db)
m.AddMigrations(
sqlutil.Migration{
Version: "syncapi: add history visibility column (output_room_events)",
Up: deltas.UpAddHistoryVisibilityColumnOutputRoomEvents,
},
)
err = m.Up(context.Background())
if err != nil {
return nil, err
}
return s, sqlutil.StatementList{
{&s.insertEventStmt, insertEventSQL},
{&s.selectMaxEventIDStmt, selectMaxEventIDSQL},
{&s.updateEventJSONStmt, updateEventJSONSQL},
{&s.deleteEventsForRoomStmt, deleteEventsForRoomSQL},
{&s.selectContextEventStmt, selectContextEventSQL},
{&s.selectContextBeforeEventStmt, selectContextBeforeEventSQL},
{&s.selectContextAfterEventStmt, selectContextAfterEventSQL},
//{&s.selectSearchStmt, selectSearchSQL}, - prepared at runtime
}.Prepare(db)
}
func (s *outputRoomEventsStatements) UpdateEventJSON(ctx context.Context, txn *sql.Tx, event *gomatrixserverlib.HeaderedEvent) error {
headeredJSON, err := json.Marshal(event)
if err != nil {
return err
}
_, err = sqlutil.TxStmt(txn, s.updateEventJSONStmt).ExecContext(ctx, headeredJSON, event.EventID())
return err
}
// selectStateInRange returns the state events between the two given PDU stream positions, exclusive of oldPos, inclusive of newPos.
// Results are bucketed based on the room ID. If the same state is overwritten multiple times between the
// two positions, only the most recent state is returned.
func (s *outputRoomEventsStatements) SelectStateInRange(
ctx context.Context, txn *sql.Tx, r types.Range,
stateFilter *gomatrixserverlib.StateFilter, roomIDs []string,
) (map[string]map[string]bool, map[string]types.StreamEvent, error) {
stmtSQL := strings.Replace(selectStateInRangeSQL, "($3)", sqlutil.QueryVariadicOffset(len(roomIDs), 2), 1)
inputParams := []interface{}{
r.Low(), r.High(),
}
for _, roomID := range roomIDs {
inputParams = append(inputParams, roomID)
}
stmt, params, err := prepareWithFilters(
s.db, txn, stmtSQL, inputParams,
stateFilter.Senders, stateFilter.NotSenders,
stateFilter.Types, stateFilter.NotTypes,
nil, stateFilter.ContainsURL, stateFilter.Limit, FilterOrderAsc,
)
if err != nil {
return nil, nil, fmt.Errorf("s.prepareWithFilters: %w", err)
}
rows, err := stmt.QueryContext(ctx, params...)
if err != nil {
return nil, nil, err
}
defer rows.Close() // nolint: errcheck
// Fetch all the state change events for all rooms between the two positions then loop each event and:
// - Keep a cache of the event by ID (99% of state change events are for the event itself)
// - For each room ID, build up an array of event IDs which represents cumulative adds/removes
// For each room, map cumulative event IDs to events and return. This may need to a batch SELECT based on event ID
// if they aren't in the event ID cache. We don't handle state deletion yet.
eventIDToEvent := make(map[string]types.StreamEvent)
// RoomID => A set (map[string]bool) of state event IDs which are between the two positions
stateNeeded := make(map[string]map[string]bool)
for rows.Next() {
var (
eventID string
streamPos types.StreamPosition
eventBytes []byte
excludeFromSync bool
addIDsJSON string
delIDsJSON string
historyVisibility gomatrixserverlib.HistoryVisibility
)
if err := rows.Scan(&eventID, &streamPos, &eventBytes, &excludeFromSync, &addIDsJSON, &delIDsJSON, &historyVisibility); err != nil {
return nil, nil, err
}
addIDs, delIDs, err := unmarshalStateIDs(addIDsJSON, delIDsJSON)
if err != nil {
return nil, nil, err
}
// TODO: Handle redacted events
var ev gomatrixserverlib.HeaderedEvent
if err := ev.UnmarshalJSONWithEventID(eventBytes, eventID); err != nil {
return nil, nil, err
}
needSet := stateNeeded[ev.RoomID()]
if needSet == nil { // make set if required
needSet = make(map[string]bool)
}
for _, id := range delIDs {
needSet[id] = false
}
for _, id := range addIDs {
needSet[id] = true
}
stateNeeded[ev.RoomID()] = needSet
ev.Visibility = historyVisibility
eventIDToEvent[eventID] = types.StreamEvent{
HeaderedEvent: &ev,
StreamPosition: streamPos,
ExcludeFromSync: excludeFromSync,
}
}
return stateNeeded, eventIDToEvent, nil
}
// MaxID returns the ID of the last inserted event in this table. 'txn' is optional. If it is not supplied,
// then this function should only ever be used at startup, as it will race with inserting events if it is
// done afterwards. If there are no inserted events, 0 is returned.
func (s *outputRoomEventsStatements) SelectMaxEventID(
ctx context.Context, txn *sql.Tx,
) (id int64, err error) {
var nullableID sql.NullInt64
stmt := sqlutil.TxStmt(txn, s.selectMaxEventIDStmt)
err = stmt.QueryRowContext(ctx).Scan(&nullableID)
if nullableID.Valid {
id = nullableID.Int64
}
return
}
// InsertEvent into the output_room_events table. addState and removeState are an optional list of state event IDs. Returns the position
// of the inserted event.
func (s *outputRoomEventsStatements) InsertEvent(
ctx context.Context, txn *sql.Tx,
event *gomatrixserverlib.HeaderedEvent, addState, removeState []string,
transactionID *api.TransactionID, excludeFromSync bool, historyVisibility gomatrixserverlib.HistoryVisibility,
) (types.StreamPosition, error) {
var txnID *string
var sessionID *int64
if transactionID != nil {
sessionID = &transactionID.SessionID
txnID = &transactionID.TransactionID
}
// Parse content as JSON and search for an "url" key
containsURL := false
var content map[string]interface{}
if json.Unmarshal(event.Content(), &content) == nil {
// Set containsURL to true if url is present
_, containsURL = content["url"]
}
var headeredJSON []byte
headeredJSON, err := json.Marshal(event)
if err != nil {
return 0, err
}
var addStateJSON, removeStateJSON []byte
if len(addState) > 0 {
addStateJSON, err = json.Marshal(addState)
}
if err != nil {
return 0, fmt.Errorf("json.Marshal(addState): %w", err)
}
if len(removeState) > 0 {
removeStateJSON, err = json.Marshal(removeState)
}
if err != nil {
return 0, fmt.Errorf("json.Marshal(removeState): %w", err)
}
streamPos, err := s.streamIDStatements.nextPDUID(ctx, txn)
if err != nil {
return 0, err
}
insertStmt := sqlutil.TxStmt(txn, s.insertEventStmt)
_, err = insertStmt.ExecContext(
ctx,
streamPos,
event.RoomID(),
event.EventID(),
headeredJSON,
event.Type(),
event.Sender(),
containsURL,
string(addStateJSON),
string(removeStateJSON),
sessionID,
txnID,
excludeFromSync,
historyVisibility,
excludeFromSync,
)
return streamPos, err
}
func (s *outputRoomEventsStatements) SelectRecentEvents(
ctx context.Context, txn *sql.Tx,
roomID string, r types.Range, eventFilter *gomatrixserverlib.RoomEventFilter,
chronologicalOrder bool, onlySyncEvents bool,
) ([]types.StreamEvent, bool, error) {
var query string
if onlySyncEvents {
query = selectRecentEventsForSyncSQL
} else {
query = selectRecentEventsSQL
}
stmt, params, err := prepareWithFilters(
s.db, txn, query,
[]interface{}{
roomID, r.Low(), r.High(),
},
eventFilter.Senders, eventFilter.NotSenders,
eventFilter.Types, eventFilter.NotTypes,
nil, eventFilter.ContainsURL, eventFilter.Limit+1, FilterOrderDesc,
)
if err != nil {
return nil, false, fmt.Errorf("s.prepareWithFilters: %w", err)
}
rows, err := stmt.QueryContext(ctx, params...)
if err != nil {
return nil, false, err
}
defer internal.CloseAndLogIfError(ctx, rows, "selectRecentEvents: rows.close() failed")
events, err := rowsToStreamEvents(rows)
if err != nil {
return nil, false, err
}
if chronologicalOrder {
// The events need to be returned from oldest to latest, which isn't
// necessary the way the SQL query returns them, so a sort is necessary to
// ensure the events are in the right order in the slice.
sort.SliceStable(events, func(i int, j int) bool {
return events[i].StreamPosition < events[j].StreamPosition
})
}
// we queried for 1 more than the limit, so if we returned one more mark limited=true
limited := false
if len(events) > eventFilter.Limit {
limited = true
// re-slice the extra (oldest) event out: in chronological order this is the first entry, else the last.
if chronologicalOrder {
events = events[1:]
} else {
events = events[:len(events)-1]
}
}
return events, limited, nil
}
func (s *outputRoomEventsStatements) SelectEarlyEvents(
ctx context.Context, txn *sql.Tx,
roomID string, r types.Range, eventFilter *gomatrixserverlib.RoomEventFilter,
) ([]types.StreamEvent, error) {
stmt, params, err := prepareWithFilters(
s.db, txn, selectEarlyEventsSQL,
[]interface{}{
roomID, r.Low(), r.High(),
},
eventFilter.Senders, eventFilter.NotSenders,
eventFilter.Types, eventFilter.NotTypes,
nil, eventFilter.ContainsURL, eventFilter.Limit, FilterOrderAsc,
)
if err != nil {
return nil, fmt.Errorf("s.prepareWithFilters: %w", err)
}
rows, err := stmt.QueryContext(ctx, params...)
if err != nil {
return nil, err
}
defer internal.CloseAndLogIfError(ctx, rows, "selectEarlyEvents: rows.close() failed")
events, err := rowsToStreamEvents(rows)
if err != nil {
return nil, err
}
// The events need to be returned from oldest to latest, which isn't
// necessarily the way the SQL query returns them, so a sort is necessary to
// ensure the events are in the right order in the slice.
sort.SliceStable(events, func(i int, j int) bool {
return events[i].StreamPosition < events[j].StreamPosition
})
return events, nil
}
// selectEvents returns the events for the given event IDs. If an event is
// missing from the database, it will be omitted.
func (s *outputRoomEventsStatements) SelectEvents(
ctx context.Context, txn *sql.Tx, eventIDs []string, filter *gomatrixserverlib.RoomEventFilter, preserveOrder bool,
) ([]types.StreamEvent, error) {
iEventIDs := make([]interface{}, len(eventIDs))
for i := range eventIDs {
iEventIDs[i] = eventIDs[i]
}
selectSQL := strings.Replace(selectEventsSQL, "($1)", sqlutil.QueryVariadic(len(eventIDs)), 1)
if filter == nil {
filter = &gomatrixserverlib.RoomEventFilter{Limit: 20}
}
stmt, params, err := prepareWithFilters(
s.db, txn, selectSQL, iEventIDs,
filter.Senders, filter.NotSenders,
filter.Types, filter.NotTypes,
nil, filter.ContainsURL, filter.Limit, FilterOrderAsc,
)
if err != nil {
return nil, err
}
rows, err := stmt.QueryContext(ctx, params...)
if err != nil {
return nil, err
}
defer internal.CloseAndLogIfError(ctx, rows, "selectEvents: rows.close() failed")
streamEvents, err := rowsToStreamEvents(rows)
if err != nil {
return nil, err
}
if preserveOrder {
var returnEvents []types.StreamEvent
eventMap := make(map[string]types.StreamEvent)
for _, ev := range streamEvents {
eventMap[ev.EventID()] = ev
}
for _, eventID := range eventIDs {
ev, ok := eventMap[eventID]
if ok {
returnEvents = append(returnEvents, ev)
}
}
return returnEvents, nil
}
return streamEvents, nil
}
func (s *outputRoomEventsStatements) DeleteEventsForRoom(
ctx context.Context, txn *sql.Tx, roomID string,
) (err error) {
_, err = sqlutil.TxStmt(txn, s.deleteEventsForRoomStmt).ExecContext(ctx, roomID)
return err
}
func rowsToStreamEvents(rows *sql.Rows) ([]types.StreamEvent, error) {
var result []types.StreamEvent
for rows.Next() {
var (
eventID string
streamPos types.StreamPosition
eventBytes []byte
excludeFromSync bool
sessionID *int64
txnID *string
transactionID *api.TransactionID
historyVisibility gomatrixserverlib.HistoryVisibility
)
if err := rows.Scan(&eventID, &streamPos, &eventBytes, &sessionID, &excludeFromSync, &txnID, &historyVisibility); err != nil {
return nil, err
}
// TODO: Handle redacted events
var ev gomatrixserverlib.HeaderedEvent
if err := ev.UnmarshalJSONWithEventID(eventBytes, eventID); err != nil {
return nil, err
}
if sessionID != nil && txnID != nil {
transactionID = &api.TransactionID{
SessionID: *sessionID,
TransactionID: *txnID,
}
}
ev.Visibility = historyVisibility
result = append(result, types.StreamEvent{
HeaderedEvent: &ev,
StreamPosition: streamPos,
TransactionID: transactionID,
ExcludeFromSync: excludeFromSync,
})
}
return result, nil
}
func (s *outputRoomEventsStatements) SelectContextEvent(
ctx context.Context, txn *sql.Tx, roomID, eventID string,
) (id int, evt gomatrixserverlib.HeaderedEvent, err error) {
row := sqlutil.TxStmt(txn, s.selectContextEventStmt).QueryRowContext(ctx, roomID, eventID)
var eventAsString string
var historyVisibility gomatrixserverlib.HistoryVisibility
if err = row.Scan(&id, &eventAsString, &historyVisibility); err != nil {
return 0, evt, err
}
if err = json.Unmarshal([]byte(eventAsString), &evt); err != nil {
return 0, evt, err
}
evt.Visibility = historyVisibility
return id, evt, nil
}
func (s *outputRoomEventsStatements) SelectContextBeforeEvent(
ctx context.Context, txn *sql.Tx, id int, roomID string, filter *gomatrixserverlib.RoomEventFilter,
) (evts []*gomatrixserverlib.HeaderedEvent, err error) {
stmt, params, err := prepareWithFilters(
s.db, txn, selectContextBeforeEventSQL,
[]interface{}{
roomID, id,
},
filter.Senders, filter.NotSenders,
filter.Types, filter.NotTypes,
nil, filter.ContainsURL, filter.Limit, FilterOrderDesc,
)
rows, err := stmt.QueryContext(ctx, params...)
if err != nil {
return
}
defer internal.CloseAndLogIfError(ctx, rows, "rows.close() failed")
for rows.Next() {
var (
eventBytes []byte
evt *gomatrixserverlib.HeaderedEvent
historyVisibility gomatrixserverlib.HistoryVisibility
)
if err = rows.Scan(&eventBytes, &historyVisibility); err != nil {
return evts, err
}
if err = json.Unmarshal(eventBytes, &evt); err != nil {
return evts, err
}
evt.Visibility = historyVisibility
evts = append(evts, evt)
}
return evts, rows.Err()
}
func (s *outputRoomEventsStatements) SelectContextAfterEvent(
ctx context.Context, txn *sql.Tx, id int, roomID string, filter *gomatrixserverlib.RoomEventFilter,
) (lastID int, evts []*gomatrixserverlib.HeaderedEvent, err error) {
stmt, params, err := prepareWithFilters(
s.db, txn, selectContextAfterEventSQL,
[]interface{}{
roomID, id,
},
filter.Senders, filter.NotSenders,
filter.Types, filter.NotTypes,
nil, filter.ContainsURL, filter.Limit, FilterOrderAsc,
)
rows, err := stmt.QueryContext(ctx, params...)
if err != nil {
return
}
defer internal.CloseAndLogIfError(ctx, rows, "rows.close() failed")
for rows.Next() {
var (
eventBytes []byte
evt *gomatrixserverlib.HeaderedEvent
historyVisibility gomatrixserverlib.HistoryVisibility
)
if err = rows.Scan(&lastID, &eventBytes, &historyVisibility); err != nil {
return 0, evts, err
}
if err = json.Unmarshal(eventBytes, &evt); err != nil {
return 0, evts, err
}
evt.Visibility = historyVisibility
evts = append(evts, evt)
}
return lastID, evts, rows.Err()
}
func unmarshalStateIDs(addIDsJSON, delIDsJSON string) (addIDs []string, delIDs []string, err error) {
if len(addIDsJSON) > 0 {
if err = json.Unmarshal([]byte(addIDsJSON), &addIDs); err != nil {
return
}
}
if len(delIDsJSON) > 0 {
if err = json.Unmarshal([]byte(delIDsJSON), &delIDs); err != nil {
return
}
}
return
}
func (s *outputRoomEventsStatements) ReIndex(ctx context.Context, txn *sql.Tx, limit, afterID int64, types []string) (map[int64]gomatrixserverlib.HeaderedEvent, error) {
params := make([]interface{}, len(types))
for i := range types {
params[i] = types[i]
}
params = append(params, afterID)
params = append(params, limit)
selectSQL := strings.Replace(selectSearchSQL, "($1)", sqlutil.QueryVariadic(len(types)), 1)
stmt, err := s.db.Prepare(selectSQL)
if err != nil {
return nil, err
}
defer internal.CloseAndLogIfError(ctx, stmt, "selectEvents: stmt.close() failed")
rows, err := sqlutil.TxStmt(txn, stmt).QueryContext(ctx, params...)
if err != nil {
return nil, err
}
defer internal.CloseAndLogIfError(ctx, rows, "rows.close() failed")
var eventID string
var id int64
result := make(map[int64]gomatrixserverlib.HeaderedEvent)
for rows.Next() {
var ev gomatrixserverlib.HeaderedEvent
var eventBytes []byte
if err = rows.Scan(&id, &eventID, &eventBytes); err != nil {
return nil, err
}
if err = ev.UnmarshalJSONWithEventID(eventBytes, eventID); err != nil {
return nil, err
}
result[id] = ev
}
return result, rows.Err()
}