More SQLite (#871)

* SQLite support for appservice

* SQLite support for mediaapi

* Copyright notices

* SQLite for public rooms API (although with some slight differences in behaviour)

* Lazy match aliases, add TODOs

appservice/storage/sqlite3/storage.go

@@ -0,0 +1,111 @@
+// Copyright 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"
+
+	// Import SQLite database driver
+	"github.com/matrix-org/gomatrixserverlib"
+	_ "github.com/mattn/go-sqlite3"
+)
+
+// Database stores events intended to be later sent to application services
+type Database struct {
+	events eventsStatements
+	txnID  txnStatements
+	db     *sql.DB
+}
+
+// NewDatabase opens a new database
+func NewDatabase(dataSourceName string) (*Database, error) {
+	var result Database
+	var err error
+	if result.db, err = sql.Open("sqlite3", dataSourceName); err != nil {
+		return nil, err
+	}
+	if err = result.prepare(); err != nil {
+		return nil, err
+	}
+	return &result, nil
+}
+
+func (d *Database) prepare() error {
+	if err := d.events.prepare(d.db); err != nil {
+		return err
+	}
+
+	return d.txnID.prepare(d.db)
+}
+
+// StoreEvent takes in a gomatrixserverlib.Event and stores it in the database
+// for a transaction worker to pull and later send to an application service.
+func (d *Database) StoreEvent(
+	ctx context.Context,
+	appServiceID string,
+	event *gomatrixserverlib.Event,
+) error {
+	return d.events.insertEvent(ctx, appServiceID, event)
+}
+
+// GetEventsWithAppServiceID returns a slice of events and their IDs intended to
+// be sent to an application service given its ID.
+func (d *Database) GetEventsWithAppServiceID(
+	ctx context.Context,
+	appServiceID string,
+	limit int,
+) (int, int, []gomatrixserverlib.Event, bool, error) {
+	return d.events.selectEventsByApplicationServiceID(ctx, appServiceID, limit)
+}
+
+// CountEventsWithAppServiceID returns the number of events destined for an
+// application service given its ID.
+func (d *Database) CountEventsWithAppServiceID(
+	ctx context.Context,
+	appServiceID string,
+) (int, error) {
+	return d.events.countEventsByApplicationServiceID(ctx, appServiceID)
+}
+
+// UpdateTxnIDForEvents takes in an application service ID and a
+// and stores them in the DB, unless the pair already exists, in
+// which case it updates them.
+func (d *Database) UpdateTxnIDForEvents(
+	ctx context.Context,
+	appserviceID string,
+	maxID, txnID int,
+) error {
+	return d.events.updateTxnIDForEvents(ctx, appserviceID, maxID, txnID)
+}
+
+// RemoveEventsBeforeAndIncludingID removes all events from the database that
+// are less than or equal to a given maximum ID. IDs here are implemented as a
+// serial, thus this should always delete events in chronological order.
+func (d *Database) RemoveEventsBeforeAndIncludingID(
+	ctx context.Context,
+	appserviceID string,
+	eventTableID int,
+) error {
+	return d.events.deleteEventsBeforeAndIncludingID(ctx, appserviceID, eventTableID)
+}
+
+// GetLatestTxnID returns the latest available transaction id
+func (d *Database) GetLatestTxnID(
+	ctx context.Context,
+) (int, error) {
+	return d.txnID.selectTxnID(ctx)
+}