import {GristWSConnection} from 'app/client/components/GristWSConnection'; import {TableFetchResult} from 'app/common/ActiveDocAPI'; import {UserAPIImpl} from 'app/common/UserAPI'; import {delay} from 'app/common/delay'; import {cookieName} from 'app/server/lib/gristSessions'; import * as log from 'app/server/lib/log'; import {getGristConfig} from 'test/gen-server/testUtils'; import {prepareDatabase} from 'test/server/lib/helpers/PrepareDatabase'; import {TestServer} from 'test/server/lib/helpers/TestServer'; import {createTestDir, EnvironmentSnapshot, setTmpLogLevel} from 'test/server/testUtils'; import {assert} from 'chai'; import * as cookie from 'cookie'; import fetch from 'node-fetch'; import WebSocket from 'ws'; describe('ManyFetches', function() { this.timeout(30000); setTmpLogLevel('warn'); // Set to 'info' to see what heap size actually is. let oldEnv: EnvironmentSnapshot; const userName = 'chimpy'; const email = 'chimpy@getgrist.com'; const org = 'docs'; let home: TestServer; let docs: TestServer; let userApi: UserAPIImpl; beforeEach(async function() { oldEnv = new EnvironmentSnapshot(); // Needed for prepareDatabase, which changes process.env log.info("Starting servers"); const testDir = await createTestDir("ManyFetches"); await prepareDatabase(testDir); home = await TestServer.startServer('home', testDir, "home"); docs = await TestServer.startServer('docs', testDir, "docs", { // The test verifies memory usage by checking heap sizes. The line below limits doc-worker // process so that it crashes when memory management is wrong. With fetch sizes // in this test, doc-worker's heap size goes from ~90M to ~330M without memory management; // this limit is in the middle as another way to verify that memory management helps. // Without this limit, there is no pressure on node to garbage-collect, so it may use more // memory than we expect, making the test less reliable. NODE_OPTIONS: '--max-old-space-size=210', }, home.serverUrl); userApi = home.makeUserApi(org, userName); }); afterEach(async function() { // stop all servers await home.stop(); await docs.stop(); oldEnv.restore(); }); // Assert and log; helpful for working on the test (when setTmpLogLevel is 'info'). function assertIsBelow(value: number, expected: number) { log.info("HeapMB", value, `(expected < ${expected})`); assert.isBelow(value, expected); } it('should limit the memory used to respond to many simultaneuous fetches', async function() { // Here we create a large document, and fetch it in parallel 200 times, without reading // responses. This test relies on the fact that the server caches the fetched data, so only // the serialized responses to clients are responsible for large memory use. This is the // memory use limited in Client.ts by jsonMemoryPool. // Reduce the limit controlling memory for JSON responses from the default of 500MB to 50MB. await docs.testingHooks.commSetClientJsonMemoryLimit(50 * 1024 * 1024); // Create a large document where fetches would have a noticeable memory footprint. // 40k rows should produce ~2MB fetch response. const {docId} = await createLargeDoc({rows: 40_000}); // When we get results, here's a checker that it looks reasonable. function checkResults(results: TableFetchResult[]) { assert.lengthOf(results, 100); for (const res of results) { assert.lengthOf(res.tableData[2], 40_000); assert.lengthOf(res.tableData[3].Num, 40_000); assert.lengthOf(res.tableData[3].Text, 40_000); } } // Prepare to make N requests. For N=100, doc-worker should need ~200M of additional memory // without memory management. const N = 100; // Helper to get doc-worker's heap size. // If the server dies, testingHooks calls may hang. This wrapper prevents that. const serverErrorPromise = docs.getExitPromise().then(() => { throw new Error("server exited"); }); const getMemoryUsage = () => Promise.race([docs.testingHooks.getMemoryUsage(), serverErrorPromise]); const getHeapMB = async () => Math.round((await getMemoryUsage() as NodeJS.MemoryUsage).heapUsed /1024/1024); assertIsBelow(await getHeapMB(), 120); // Create all the connections, but don't make the fetches just yet. const createConnectionFunc = await prepareGristWSConnection(docId); const connectionsA = Array.from(Array(N), createConnectionFunc); const fetchersA = await Promise.all(connectionsA.map(c => connect(c, docId))); const connectionsB = Array.from(Array(N), createConnectionFunc); const fetchersB = await Promise.all(connectionsB.map(c => connect(c, docId))); try { assertIsBelow(await getHeapMB(), 120); // Start fetches without reading responses. This is a step that should push memory limits. fetchersA.map(f => f.startPausedFetch()); // Give it a few seconds, enough for server to use what memory it can. await delay(2000); assertIsBelow(await getHeapMB(), 200); // Make N more requests. See that memory hasn't spiked. fetchersB.map(f => f.startPausedFetch()); await delay(2000); assertIsBelow(await getHeapMB(), 200); // Complete the first batch of requests. This allows for the fetches to complete, and for // memory to get released. Also check that results look reasonable. checkResults(await Promise.all(fetchersA.map(f => f.completeFetch()))); assertIsBelow(await getHeapMB(), 200); // Complete the outstanding requests. Memory shouldn't spike. checkResults(await Promise.all(fetchersB.map(f => f.completeFetch()))); assertIsBelow(await getHeapMB(), 200); } finally { fetchersA.map(f => f.end()); fetchersB.map(f => f.end()); } }); // Creates a document with the given number of rows, and about 50 bytes per row. async function createLargeDoc({rows}: {rows: number}): Promise<{docId: string}> { log.info("Preparing a doc of %s rows", rows); const ws = (await userApi.getOrgWorkspaces('current'))[0].id; const docId = await userApi.newDoc({name: 'testdoc'}, ws); await userApi.applyUserActions(docId, [['AddTable', 'TestTable', [ {id: 'Num', type: 'Numeric'}, {id: 'Text', type: 'Text'} ]]]); const chunk = 10_000; for (let i = 0; i < rows; i += chunk) { const currentNumRows = Math.min(chunk, rows - i); await userApi.getDocAPI(docId).addRows('TestTable', { // Roughly 8 bytes per row Num: Array.from(Array(currentNumRows), (_, n) => (i + n) * 100), // Roughly 40 bytes per row Text: Array.from(Array(currentNumRows), (_, n) => `Hello, world, again for the ${i + n}th time.`), }); } return {docId}; } // Get all the info for how to create a GristWSConnection, and returns a connection-creating // function. async function prepareGristWSConnection(docId: string): Promise<() => GristWSConnection> { // Use cookies for access to stay as close as possible to regular operation. const resp = await fetch(`${home.serverUrl}/test/session`); const sid = cookie.parse(resp.headers.get('set-cookie'))[cookieName]; if (!sid) { throw new Error('no session available'); } await home.testingHooks.setLoginSessionProfile(sid, {name: userName, email}, org); // Load the document html. const pageUrl = `${home.serverUrl}/o/docs/doc/${docId}`; const headers = {Cookie: `${cookieName}=${sid}`}; const doc = await fetch(pageUrl, {headers}); const pageBody = await doc.text(); // Pull out the configuration object embedded in the html. const gristConfig = getGristConfig(pageBody); const {assignmentId, getWorker, homeUrl} = gristConfig; if (!homeUrl) { throw new Error('no homeUrl'); } if (!assignmentId) { throw new Error('no assignmentId'); } const docWorkerUrl = getWorker && getWorker[assignmentId]; if (!docWorkerUrl) { throw new Error('no docWorkerUrl'); } // Place the config object in window.gristConfig as if we were a // real browser client. GristWSConnection expects to find it there. globalThis.window = globalThis.window || {}; (globalThis.window as any).gristConfig = gristConfig; // We return a function that constructs a GristWSConnection. return function createConnectionFunc() { let clientId: string = '0'; return GristWSConnection.create(null, { makeWebSocket(url: string): any { return new WebSocket(url, undefined, { headers }); }, getTimezone() { return Promise.resolve('UTC'); }, getPageUrl() { return pageUrl; }, getDocWorkerUrl() { return Promise.resolve(docWorkerUrl); }, getClientId(did) { return clientId; }, getUserSelector() { return ''; }, updateClientId(did: string, cid: string) { clientId = cid; }, advanceCounter(): string { return '0'; }, log(msg, ...args) {}, warn(msg, ...args) {}, }); }; } // Actually connect GristWSConnection, open the doc, and return a few methods for next steps. async function connect(connection: GristWSConnection, docId: string) { async function getMessage(eventType: string, filter: (msg: T) => boolean): Promise { return new Promise(resolve => { function callback(msg: T) { if (filter(msg)) { connection.off(eventType, callback); resolve(msg); } } connection.on(eventType, callback); }); } // Launch the websocket const connectionPromise = getMessage('connectState', (isConnected: boolean) => isConnected); connection.initialize(null); await connectionPromise; // Wait for connection to succeed. const openPromise = getMessage('serverMessage', ({reqId}: {reqId?: number}) => (reqId === 0)); connection.send(JSON.stringify({reqId: 0, method: 'openDoc', args: [docId]})); await openPromise; let fetchPromise: Promise; return { startPausedFetch: () => { fetchPromise = getMessage('serverMessage', ({reqId}: {reqId?: number}) => (reqId === 1)); (connection as any)._ws.pause(); connection.send(JSON.stringify({reqId: 1, method: 'fetchTable', args: [0, 'TestTable']})); }, completeFetch: async (): Promise => { (connection as any)._ws.resume(); return (await fetchPromise as any).data; }, end: () => { connection.dispose(); }, }; } });