1 files changed, 200 insertions, 0 deletions
diff --git a/tests/runner/selenium/browsers.js b/tests/runner/selenium/browsers.js
new file mode 100644
index 000000000..568d6ed36
--- /dev/null
+++ b/tests/runner/selenium/browsers.js
@@ -0,0 +1,200 @@
+import chalk from "chalk";
+import { getBrowserString } from "../lib/getBrowserString.js";
+import createDriver from "./createDriver.js";
+
+const workers = Object.create( null );
+
+/**
+ * Keys are browser strings
+ * Structure of a worker:
+ * {
+ * 	 debug: boolean, // Stops the worker from being cleaned up when finished
+ *   id: string,
+ *   lastTouch: number, // The last time a request was received
+ *   url: string,
+ *   browser: object, // The browser object
+ *   options: object // The options to create the worker
+ * }
+ */
+
+// Acknowledge the worker within the time limit.
+const ACKNOWLEDGE_INTERVAL = 1000;
+const ACKNOWLEDGE_TIMEOUT = 60 * 1000 * 1;
+
+const MAX_WORKER_RESTARTS = 5;
+
+// No report after the time limit
+// should refresh the worker
+const RUN_WORKER_TIMEOUT = 60 * 1000 * 2;
+
+const WORKER_WAIT_TIME = 30000;
+
+// Limit concurrency to 8 by default in selenium
+const MAX_CONCURRENCY = 8;
+
+export function touchBrowser( browser ) {
+	const fullBrowser = getBrowserString( browser );
+	const worker = workers[ fullBrowser ];
+	if ( worker ) {
+		worker.lastTouch = Date.now();
+	}
+}
+
+async function waitForAck( worker, { fullBrowser, verbose } ) {
+	delete worker.lastTouch;
+	return new Promise( ( resolve, reject ) => {
+		const interval = setInterval( () => {
+			if ( worker.lastTouch ) {
+				if ( verbose ) {
+					console.log( `\n${ fullBrowser } acknowledged.` );
+				}
+				clearTimeout( timeout );
+				clearInterval( interval );
+				resolve();
+			}
+		}, ACKNOWLEDGE_INTERVAL );
+
+		const timeout = setTimeout( () => {
+			clearInterval( interval );
+			reject(
+				new Error(
+					`${ fullBrowser } not acknowledged after ${
+						ACKNOWLEDGE_TIMEOUT / 1000 / 60
+					}min.`
+				)
+			);
+		}, ACKNOWLEDGE_TIMEOUT );
+	} );
+}
+
+async function restartWorker( worker ) {
+	await cleanupWorker( worker, worker.options );
+	await createBrowserWorker(
+		worker.url,
+		worker.browser,
+		worker.options,
+		worker.restarts + 1
+	);
+}
+
+async function ensureAcknowledged( worker ) {
+	const fullBrowser = getBrowserString( worker.browser );
+	const verbose = worker.options.verbose;
+	try {
+		await waitForAck( worker, { fullBrowser, verbose } );
+		return worker;
+	} catch ( error ) {
+		console.error( error.message );
+		await restartWorker( worker );
+	}
+}
+
+export async function createBrowserWorker( url, browser, options, restarts = 0 ) {
+	if ( restarts > MAX_WORKER_RESTARTS ) {
+		throw new Error(
+			`Reached the maximum number of restarts for ${ chalk.yellow(
+				getBrowserString( browser )
+			) }`
+		);
+	}
+	const { concurrency = MAX_CONCURRENCY, debug, headless, verbose } = options;
+	while ( workers.length >= concurrency ) {
+		if ( verbose ) {
+			console.log( "\nWaiting for available sessions..." );
+		}
+		await new Promise( ( resolve ) => setTimeout( resolve, WORKER_WAIT_TIME ) );
+	}
+
+	const fullBrowser = getBrowserString( browser );
+
+	const driver = await createDriver( {
+		browserName: browser.browser,
+		headless,
+		url,
+		verbose
+	} );
+
+	const worker = {
+		debug: !!debug,
+		driver,
+		url,
+		browser,
+		restarts,
+		options
+	};
+
+	worker.debug = !!debug;
+	worker.url = url;
+	worker.browser = browser;
+	worker.restarts = restarts;
+	worker.options = options;
+	touchBrowser( browser );
+	workers[ fullBrowser ] = worker;
+
+	// Wait for the worker to show up in the list
+	// before returning it.
+	return ensureAcknowledged( worker );
+}
+
+export async function setBrowserWorkerUrl( browser, url ) {
+	const fullBrowser = getBrowserString( browser );
+	const worker = workers[ fullBrowser ];
+	if ( worker ) {
+		worker.url = url;
+	}
+}
+
+/**
+ * Checks that all browsers have received
+ * a response in the given amount of time.
+ * If not, the worker is restarted.
+ */
+export async function checkLastTouches() {
+	for ( const [ fullBrowser, worker ] of Object.entries( workers ) ) {
+		if ( Date.now() - worker.lastTouch > RUN_WORKER_TIMEOUT ) {
+			const options = worker.options;
+			if ( options.verbose ) {
+				console.log(
+					`\nNo response from ${ chalk.yellow( fullBrowser ) } in ${
+						RUN_WORKER_TIMEOUT / 1000 / 60
+					}min.`
+				);
+			}
+			await restartWorker( worker );
+		}
+	}
+}
+
+export async function cleanupWorker( worker, { verbose } ) {
+	for ( const [ fullBrowser, w ] of Object.entries( workers ) ) {
+		if ( w === worker ) {
+			delete workers[ fullBrowser ];
+			await w.driver.quit();
+			if ( verbose ) {
+				console.log( `\nStopped ${ fullBrowser }.` );
+			}
+			return;
+		}
+	}
+}
+
+export async function cleanupAllBrowsers( { verbose } ) {
+	const workersRemaining = Object.values( workers );
+	const numRemaining = workersRemaining.length;
+	if ( numRemaining ) {
+		try {
+			await Promise.all(
+				workersRemaining.map( ( worker ) => worker.driver.quit() )
+			);
+			if ( verbose ) {
+				console.log(
+					`Stopped ${ numRemaining } browser${ numRemaining > 1 ? "s" : "" }.`
+				);
+			}
+		} catch ( error ) {
+
+			// Log the error, but do not consider the test run failed
+			console.error( error );
+		}
+	}
+}