Test drive never starting because of failed connection to VMServiceFlutterDriver

[bartekpacia]

See this workflow run. Out of 6 jobs, 3 succeeded, 1 failed, and 2 timed out. This issue is about getting rid of those timeouts.

It looks that sometimes Flutter Driver can't connect to the service running on the Dart VM, and waits indefinitely.

This how logs from the "corrupt" state look like:

Patrol automation server is running, starting test drive
VMServiceFlutterDriver: Connecting to Flutter application at http://127.0.0.1:50087/DCSwv2oETPg=/
VMServiceFlutterDriver: Isolate found with number: 380803021374111
VMServiceFlutterDriver: Unknown pause event type Event. Assuming application is ready.
VMServiceFlutterDriver: Flutter Driver extension is taking a long time to become available. Ensure your test app (often "lib/main.dart") imports "package:flutter_driver/driver_extension.dart" and calls enableFlutterDriverExtension() as the first call in main().

And this is how logs look like when everything is OK:

Patrol automation server is running, starting test drive
VMServiceFlutterDriver: Connecting to Flutter application at http://127.0.0.1:49741/_Om3Er0LaIw=/
VMServiceFlutterDriver: Isolate found with number: 628925095143275
VMServiceFlutterDriver: Isolate is paused at start.
VMServiceFlutterDriver: Attempting to resume isolate
Patrol: creating Patrol, host: localhost, port: 8081, verbose: true

The solution I'd try out is to check for logs containing, for example VMServiceFlutterDrive: VMServiceFlutterDriver: Unknown pause event type Event. Assuming application is ready. and if it occurs, try to connect once again. We could also go the other way around and wait for the connection for a few seconds and then try to reconnect.

[bartekpacia]

The possible solution I mentioned above doesn't work. If the driver can't connect for the first time, then it can't connect for the 2nd, 3rd, and n-th time as well. That's why I reverted the PRs (see above).

Another approach that we could try: look into replacing the default integration driver (in test_driver/integration_test.dart):

import 'package:integration_test/integration_test_driver.dart';

Future<void> main() => integrationDriver();

with something ours that would have retry semantics.

See also:

• integrationDriver API reference

[bartekpacia]

See this issue:

• Connect to VM timeout when doing integration tests flutter/flutter#50898

[bartekpacia]

We've freed ourselves from flutter_driver thanks to #646.

[github-actions]

This issue has been automatically locked since there has not been any recent activity after it was closed. If you are still experiencing a similar problem, please file a new issue. Make sure to follow the template and provide all the information necessary to reproduce the issue.