import { RequestAbortError, HomeServerError, StorageError } from "./error.js"; import EventEmitter from "../EventEmitter.js"; const INCREMENTAL_TIMEOUT = 30000; const SYNC_EVENT_LIMIT = 10; function parseRooms(roomsSection, roomCallback) { if (!roomsSection) { return; } const allMemberships = ["join", "invite", "leave"]; for(const membership of allMemberships) { const membershipSection = roomsSection[membership]; if (membershipSection) { const rooms = Object.entries(membershipSection) for (const [roomId, roomResponse] of rooms) { roomCallback(roomId, roomResponse, membership); } } } } export default class Sync extends EventEmitter { constructor(hsApi, session, storage) { super(); this._hsApi = hsApi; this._session = session; this._storage = storage; this._isSyncing = false; this._currentRequest = null; } // returns when initial sync is done async start() { if (this._isSyncing) { return; } this._isSyncing = true; let syncToken = this._session.syncToken; // do initial sync if needed if (!syncToken) { // need to create limit filter here syncToken = await this._syncRequest(); } this._syncLoop(syncToken); } async _syncLoop(syncToken) { // if syncToken is falsy, it will first do an initial sync ... while(this._isSyncing) { try { console.log(`starting sync request with since ${syncToken} ...`); syncToken = await this._syncRequest(syncToken, INCREMENTAL_TIMEOUT); } catch (err) { this._isSyncing = false; if (!(err instanceof RequestAbortError)) { console.warn("stopping sync because of error"); this.emit("error", err); } } } this.emit("stopped"); } async _syncRequest(syncToken, timeout) { this._currentRequest = this._hsApi.sync(syncToken, undefined, timeout); const response = await this._currentRequest.response(); syncToken = response.next_batch; const storeNames = this._storage.storeNames; const syncTxn = await this._storage.readWriteTxn([ storeNames.session, storeNames.roomSummary, storeNames.roomTimeline, storeNames.roomState, ]); try { this._session.applySync(syncToken, response.account_data, syncTxn); // to_device // presence if (response.rooms) { parseRooms(response.rooms, (roomId, roomResponse, membership) => { let room = this._session.rooms.get(roomId); if (!room) { room = this._session.createRoom(roomId); } console.log(` * applying sync response to room ${roomId} ...`); room.applySync(roomResponse, membership, syncTxn); }); } } catch(err) { console.warn("aborting syncTxn because of error"); // avoid corrupting state by only // storing the sync up till the point // the exception occurred syncTxn.abort(); throw err; } try { await syncTxn.complete(); console.info("syncTxn committed!!"); } catch (err) { throw new StorageError("unable to commit sync tranaction", err); } return syncToken; } stop() { if (!this._isSyncing) { return; } this._isSyncing = false; if (this._currentRequest) { this._currentRequest.abort(); this._currentRequest = null; } } }