fix: stop subscription race condition error on debug page

[warrensplayer]

Additional details

Summary
A race condition between two different subscriptions used on the Debug page was causing a GraphQL error to be shown to the user when viewing a running Cypress Cloud build. The error would have no effect on the results being shown on the page and resolve itself after the next polling cycle for the running build.

Issue
The error occurred because the RevelentRunSpecsDataSource allows the front end to pass different GraphQL fields to be returned for the relevantRunSpecChange subscription on the CloudRun type. These fields get combined into one query that is sent to Cypress Cloud.

The race condition was occurring when the following steps occurred:

• The subscription in DebugTestingProgress would run first and kick off the underlying poller in the data source and cause the first cloud query to start.
• When awaiting the return of this query, the subscription in useDebugRunSummary would be mounted and register itself to watch for emitted results. The second subscription asked for the createdAt field which is a non-nullable field as defined in the GraphQL type. The first subscription did not ask for this field.
• When the initial query returned, the value would be emitted and checked by the filter function which would only check to see if the run ids matched.
• Urql would try to resolve those initial values for the second subscription, it would show the error in the before video below due to the missing createdAt.
• Finally, the second polling cycle would run and now have both GraphQLResolveInfo objects, it would generate a GraphQL query that correctly satisfy both subscriptions.

Solution
The fix was to add an additional check to the filter function to also validate that the object being emitted had the fields asked for that particular subscription. The trade off for this solution is that the second subscription will not have accurate results for one additional polling cycle (currently 15 seconds).

Before

Screen.Recording.2023-06-26.at.9.47.26.AM.mov

After

after_trimmed.mov

Steps to test

• Visit debug page for a RUNNING build.
• No GraphQL error should be shown and page should update as expected

How has the user experience changed?

No error toast is shown when viewing a running build on the Debug page.

PR Tasks

• [-] Have tests been added/updated?
• Has a PR for user-facing changes been opened in cypress-documentation?
• Have API changes been updated in the type definitions?

[cypress]

15 flaky tests on run #48325 ↗︎

0

10227

1026

0

15

Details:

Fix linting for changelog
Project: cypress	Commit: 57df2b0de7
Status: Passed	Duration: 15:09 💡
Started: Jun 28, 2023 12:44 PM	Ended: Jun 28, 2023 12:59 PM

  create-from-component.cy.ts • 1 flaky test • app-e2e

View Output Video

Test		Artifacts
... > runs generated spec		Output Screenshots Video

  specs_list_latest_runs.cy.ts • 1 flaky test • app-e2e

View Output Video

Test		Artifacts
App/Cloud Integration - Latest runs and Average duration > when no runs are recorded > shows placeholders for all visible specs		Output Screenshots Video

  cypress-origin-communicator.cy.ts • 1 flaky test • app-e2e

View Output Video

Test		Artifacts
Cypress In Cypress Origin Communicator > cy.origin passivity with app interactions > passes upon test reload mid test execution		Output Screenshots Video

  subscriptions/configChange-subscription.cy.ts • 1 flaky test • app-e2e

View Output Video

Test		Artifacts
configChange subscription > on config page > responds to configChange event when viewport is changed		Output Screenshots Video

  e2e/origin/cookie_login.cy.ts • 1 flaky test • 5x-driver-electron

View Output Video

Test		Artifacts
... > past Max-Age, before Expires -> not logged in		Output Video

The first 5 flaky specs are shown, see all 10 specs in Cypress Cloud.

_{This comment has been generated by cypress-bot as a result of this project's GitHub integration settings.}

[lmiller1990]

Great, looks good - thanks for adding a test. I think I'd seen this before, but thought it was due to my local repo getting messed up when I changed branches, I should have looked into it more at that point.

Are you just debugging this by kicking off runs and using debug and trying different edge cases? I imagine this was a bit tricky to track down and debug.

Re: the code, I'm not sure the test description is ideal - there's a lot of complexity in the test, it might not be immediately obvious why (unless the user follows the git blame -- that might be enough, probably more informative than any test description can be).

Test description aside, this looks good.

[astone123]

This worked for me 👍🏻 thanks for fixing this!

[cypress-bot]

Released in 12.17.0.

This comment thread has been locked. If you are still experiencing this issue after upgrading to
Cypress v12.17.0, please open a new issue.