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

mediaapi/storage/sqlite3/storage.go

@@ -0,0 +1,106 @@
+// 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"
+
+	// Import the postgres database driver.
+	"github.com/matrix-org/dendrite/mediaapi/types"
+	"github.com/matrix-org/gomatrixserverlib"
+	_ "github.com/mattn/go-sqlite3"
+)
+
+// Database is used to store metadata about a repository of media files.
+type Database struct {
+	statements statements
+	db         *sql.DB
+}
+
+// Open opens a postgres database.
+func Open(dataSourceName string) (*Database, error) {
+	var d Database
+	var err error
+	if d.db, err = sql.Open("sqlite3", dataSourceName); err != nil {
+		return nil, err
+	}
+	if err = d.statements.prepare(d.db); err != nil {
+		return nil, err
+	}
+	return &d, nil
+}
+
+// StoreMediaMetadata inserts the metadata about the uploaded media into the database.
+// Returns an error if the combination of MediaID and Origin are not unique in the table.
+func (d *Database) StoreMediaMetadata(
+	ctx context.Context, mediaMetadata *types.MediaMetadata,
+) error {
+	return d.statements.media.insertMedia(ctx, mediaMetadata)
+}
+
+// GetMediaMetadata returns metadata about media stored on this server.
+// The media could have been uploaded to this server or fetched from another server and cached here.
+// Returns nil metadata if there is no metadata associated with this media.
+func (d *Database) GetMediaMetadata(
+	ctx context.Context, mediaID types.MediaID, mediaOrigin gomatrixserverlib.ServerName,
+) (*types.MediaMetadata, error) {
+	mediaMetadata, err := d.statements.media.selectMedia(ctx, mediaID, mediaOrigin)
+	if err != nil && err == sql.ErrNoRows {
+		return nil, nil
+	}
+	return mediaMetadata, err
+}
+
+// StoreThumbnail inserts the metadata about the thumbnail into the database.
+// Returns an error if the combination of MediaID and Origin are not unique in the table.
+func (d *Database) StoreThumbnail(
+	ctx context.Context, thumbnailMetadata *types.ThumbnailMetadata,
+) error {
+	return d.statements.thumbnail.insertThumbnail(ctx, thumbnailMetadata)
+}
+
+// GetThumbnail returns metadata about a specific thumbnail.
+// The media could have been uploaded to this server or fetched from another server and cached here.
+// Returns nil metadata if there is no metadata associated with this thumbnail.
+func (d *Database) GetThumbnail(
+	ctx context.Context,
+	mediaID types.MediaID,
+	mediaOrigin gomatrixserverlib.ServerName,
+	width, height int,
+	resizeMethod string,
+) (*types.ThumbnailMetadata, error) {
+	thumbnailMetadata, err := d.statements.thumbnail.selectThumbnail(
+		ctx, mediaID, mediaOrigin, width, height, resizeMethod,
+	)
+	if err != nil && err == sql.ErrNoRows {
+		return nil, nil
+	}
+	return thumbnailMetadata, err
+}
+
+// GetThumbnails returns metadata about all thumbnails for a specific media stored on this server.
+// The media could have been uploaded to this server or fetched from another server and cached here.
+// Returns nil metadata if there are no thumbnails associated with this media.
+func (d *Database) GetThumbnails(
+	ctx context.Context, mediaID types.MediaID, mediaOrigin gomatrixserverlib.ServerName,
+) ([]*types.ThumbnailMetadata, error) {
+	thumbnails, err := d.statements.thumbnail.selectThumbnails(ctx, mediaID, mediaOrigin)
+	if err != nil && err == sql.ErrNoRows {
+		return nil, nil
+	}
+	return thumbnails, err
+}