Differential D6993 Diff 23836 web/database/worker/db-worker.js

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web/database/worker/db-worker.js

	// @flow			// @flow

	import localforage from 'localforage';			import localforage from 'localforage';
				import initSqlJs from 'sql.js';

	import {			import {
	type SharedWorkerMessageEvent,			type SharedWorkerMessageEvent,
	type WorkerRequestMessage,			type WorkerRequestMessage,
	type WorkerResponseMessage,			type WorkerResponseMessage,
	workerRequestMessageTypes,			workerRequestMessageTypes,
	workerResponseMessageTypes,			workerResponseMessageTypes,
	type WorkerRequestProxyMessage,			type WorkerRequestProxyMessage,
	} from '../../types/worker-types.js';			} from '../../types/worker-types.js';
				import { SQLITE_CONTENT } from '../utils/constants.js';

	const localforageConfig: PartialConfig = {			const localforageConfig: PartialConfig = {
	driver: localforage.INDEXEDDB,			driver: localforage.INDEXEDDB,
	name: 'comm',			name: 'comm',
	storeName: 'commStorage',			storeName: 'commStorage',
	description: 'Comm encrypted database storage',			description: 'Comm encrypted database storage',
	version: '1.0',			version: '1.0',
	};			};
	localforage.config(localforageConfig);			localforage.config(localforageConfig);

	function processAppRequest(			let sqliteDb = null;

				async function initDatabase(sqljsFilePath: string, sqljsFilename: ?string) {
				const content = await localforage.getItem(SQLITE_CONTENT);

				const locateFile = defaultFilename => {
				if (sqljsFilename) {
				return `${sqljsFilePath}/${sqljsFilename}`;
				}
				return `${sqljsFilePath}/${defaultFilename}`;
				};
				const SQL = await initSqlJs({
				locateFile,
				});

				if (content) {
				sqliteDb = new SQL.Database(new Uint8Array(content));
				} else {
				sqliteDb = new SQL.Database();
				}

				const versionData = sqliteDb.exec('PRAGMA user_version;');
				if (versionData.length && versionData[0].values.length) {
				console.info(`Db version: ${versionData[0].values[0]}`);
				} else {
				throw new Error('Error while retrieving database version');
				}
				}

				async function processAppRequest(
	message: WorkerRequestMessage,			message: WorkerRequestMessage,
	): ?WorkerResponseMessage {			): Promise<?WorkerResponseMessage> {
	if (message.type === workerRequestMessageTypes.PING) {			if (message.type === workerRequestMessageTypes.PING) {
	return {			return {
	type: workerResponseMessageTypes.PONG,			type: workerResponseMessageTypes.PONG,
	text: 'PONG',			text: 'PONG',
	};			};
				} else if (message.type === workerRequestMessageTypes.INIT) {
				await initDatabase(message.sqljsFilePath, message.sqljsFilename);
				return;
	}			}

	throw new Error('Request type not supported');			throw new Error('Request type not supported');
	}			}

	function connectHandler(event: SharedWorkerMessageEvent) {			function connectHandler(event: SharedWorkerMessageEvent) {
	if (!event.ports.length) {			if (!event.ports.length) {
	return;			return;
	}			}
	const port: MessagePort = event.ports[0];			const port: MessagePort = event.ports[0];
	console.log('Web database worker alive!');			console.log('Web database worker alive!');

	port.onmessage = async function (messageEvent: MessageEvent) {			port.onmessage = async function (messageEvent: MessageEvent) {
	const data: WorkerRequestProxyMessage = (messageEvent.data: any);			const data: WorkerRequestProxyMessage = (messageEvent.data: any);
	const { id, message } = data;			const { id, message } = data;

	if (!id) {			if (!id) {
	port.postMessage({			port.postMessage({
	error: new Error('Request without identifier'),			error: new Error('Request without identifier'),
	});			});
	}			}

	try {			try {
	const result = processAppRequest(message);			const result = await processAppRequest(message);
	port.postMessage({			port.postMessage({
	id,			id,
	message: result,			message: result,
	});			});
	} catch (e) {			} catch (e) {
	port.postMessage({			port.postMessage({
	id,			id,
	error: e,			error: e,
	});			});
	}			}
	};			};
	}			}

	self.addEventListener('connect', connectHandler);			self.addEventListener('connect', connectHandler);