Improve rendering time of newly refactored "Setup Success" subtle notifications

[jimmymadon]

Feature Description

As per this comment thread, there is an increased lag when loading the newly refactored RRM Setup Success Subtle Notification compared to the legacy implementation. This could be because refactored Subtle Notifications are now not rendered immediately simultaneously in the React DOM. They are evaluated along with all other registered Error and Banner notifications and only after all the checkRequirements callbacks are run, then the topmost notification in the queue is rendered.

One additional way of solving this would be to introduce the concept of "ad-hoc" notifications which are registered and added to the queue instantaneously without the entire queue of notifications being (re)evaluated. Issue #9453 has been created to explore this possibility. Hence that issue will block this one to ensure we don't create multiple solutions unnecessarily.

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Acceptance criteria

• Setup success subtle notifications within the plugin should be rendered without any delay on page load after the setup of the feature they notify about is completed (i.e. the same effect before these notifications were refactored).

Implementation Brief

• [ ] Test, review and merge the PoC branch: https://github.com/google/site-kit-wp/compare/poc/notifications-perf
• The PoC branch:
  • [ ] Groups notifications based on their highest priorities. If the highest priorities resolve first, then they are rendered without waiting for the rest of the lower priority notifications in the queue.
  • [ ] Refactors queuing logic within the resolver into a control.

• [ ] We should console.warn() if an error is thrown by checkRequirements() to help identify bugs.

  https://github.com/google/site-kit-wp/blob/79b4417581b1cca3d718f7e55127681e6e05fc6f/assets/js/googlesitekit/notifications/datastore/notifications.js#L251

Test Coverage

QA Brief

Changelog entry

[eugene-manuilov]

Setup success subtle notifications within the plugin should be rendered without any delay on page load after the setup of the feature they notify about is completed.

@jimmymadon I don't think we should do it this way. I think we need to reconsider our main resolver to be split into area specific resolvers to make sure subtle notifications don't need to wait for other notification checks to be resolved.

[jimmymadon]

@eugene-manuilov Yes - sounds good to me. That was the original problem's solution - the only reason I mentioned the "ad-hoc" approach is because that is being investigated in #9453 as well.

Anyway, the AC here would not change though - as it is generic and just says that there should be no delay between us doing a setup and the notification being displayed.

[eugene-manuilov]

Yeah, makes sense. Thanks, @jimmymadon. AC ✔

[techanvil]

@aaemnnosttv @jimmymadon, I had the POC branch for this checked out while investigating another issue (https://github.com/google/site-kit-wp/issues/9261) and noticed a couple of issues that needed to be fixed. Evan I hope you don't mind, I've pushed the fix directly to the branch, see https://github.com/google/site-kit-wp/commit/5331d191d21105347febe19362d24c988c701ece.

The tests will of also need updating to reflect the change, but that's something that can no doubt be tackled during implementation.