Load waffle flags using React Query

[bradenmacdonald]

This PR moves waffle flags out of the redux state and loads them with React Query instead.

Features:

• the default flag values (e.g. useNewHomePage: true) will be instantly available to the application, but may change once the server responds with updated flags. If you need to not render something until you know its final value for sure, use the isLoading status.
• Likewise, within a course context, the system-wide waffle flags will be used by default until we've loaded any course-specific flags that may be set.
• A handy mockWaffleFlags() function is available for use in tests, though only one or two tests are actually using it.

TODO:

• Merge Refactor many test suites to use testUtils/initializeMocks #2067 and rebase this (update target branch)
• Add tests for the behavior described above, i.e. fallback/defaults

How to test:

Verify some waffle flags are working. For example:

1. Go to http://studio.local.openedx.io:8001/admin/waffle/flag/ and set legacy_studio.advanced_settings to True for Everyone. Now refresh, and the "Advanced Settings" menu in each course should go to the legacy Studio page. Then change it back to False (or remove it) and confirm "Advanced Settings" now stays in the MFE.
2. Verify that in courses and libraries, the contentstore.use_react_markdown_editor waffle flag controls whether or not the "Switch to markdown editor" button appears. Note that it only works in brand new problems, not editing existing ones.
   

[openedx-webhooks]

Thanks for the pull request, @bradenmacdonald!

This repository is currently maintained by @bradenmacdonald.

Once you've gone through the following steps feel free to tag them in a comment and let them know that your changes are ready for engineering review.

🔘 Get product approval

If you haven't already, check this list to see if your contribution needs to go through the product review process.

• If it does, you'll need to submit a product proposal for your contribution, and have it reviewed by the Product Working Group.
  • This process (including the steps you'll need to take) is documented here.
• If it doesn't, simply proceed with the next step.

🔘 Provide context

To help your reviewers and other members of the community understand the purpose and larger context of your changes, feel free to add as much of the following information to the PR description as you can:

• Dependencies

  This PR must be merged before / after / at the same time as ...

• Blockers

  This PR is waiting for OEP-1234 to be accepted.

• Timeline information

  This PR must be merged by XX date because ...

• Partner information

  This is for a course on edx.org.

• Supporting documentation
• Relevant Open edX discussion forum threads

🔘 Get a green build

If one or more checks are failing, continue working on your changes until this is no longer the case and your build turns green.

---

Where can I find more information?

If you'd like to get more details on all aspects of the review process for open source pull requests (OSPRs), check out the following resources:

• Overview of Review Process for Community Contributions
• Pull Request Status Guide
• Making changes to your pull request

When can I expect my changes to be merged?

Our goal is to get community contributions seen and reviewed as efficiently as possible.

However, the amount of time that it takes to review and merge a PR can vary significantly based on factors such as:

• The size and impact of the changes that it introduces
• The need for product review
• Maintenance status of the parent repository

💡 As a result it may take up to several weeks or months to complete a review and merge your PR.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 94.03%. Comparing base (9a2dac6) to head (96e7a02).
Report is 1 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #2068      +/-   ##
==========================================
+ Coverage   94.01%   94.03%   +0.01%     
==========================================
  Files        1162     1163       +1     
  Lines       24434    24441       +7     
  Branches     5187     5305     +118     
==========================================
+ Hits        22972    22982      +10     
+ Misses       1394     1382      -12     
- Partials       68       77       +9     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

[open-craft-grove]

Sandbox deployment successful 🚀
🎓 LMS
📝 Studio
ℹ️ Grove Config, Tutor Config, Tutor Requirements

[kdmccormick]

Looks great. Some non-blocking questions, one request for a longer comment.

I read the code and unit tests, and tested manually on the PR sandbox by adding contentstore.use_react_markdown_editor and confirming that it causes "Switch to Markdown editor" to show up for new problems. I tested with both:

• instance-level Waffle-on
• instance-level Waffle-off, and course-level Waffle-on

[kdmccormick]

Can you say more about these? They're not actually edx-platform defaults; rather, they're the default that we test with, right? Or do these defaults actually have significance on the app?

(I see you pulled these from an existing object in src/data/slice.js, so I'm not trying to nitpick this too much, just looking for clarity).

[bradenmacdonald]

Oh interesting. I assumed that these defaults matched the platform defaults. These are what the MFE will assume while it's waiting to load the actual values from the server. (If we don't want to assume anything, components that depend on waffle flags should block rendering until isLoading is false, but I think that's a worse experience.)

I would suggest that we follow this up with a PR to either change these defaults to match the platform defaults, or change the platform defaults to match these. But I think that should be isolated to a separate change, since this PR is trying to be an internal refactor that doesn't change behavior meaningfully.

[kdmccormick]

Yeah, I don't think you should fix these in this PR. Could you just amend your comment to say something like "frontend defaults if we fail to load flags from edx-platform -- may drift from edx-platform's actual defaults".

If you feel moved to, you could write an issue and link it here, but I'm not losing sleep over it. FWIW, my inclination here is actually "turn everything on by default in order to maximize test coverage" rather than "try to keep lockstep with edx-platform."

[bradenmacdonald]

I created a GitHub issue #2094 and put it into the comments.

[kdmccormick]

@bradenmacdonald Btw, can you confirm whether you're looking to backport this to Teak? I think it would be good to have the markdown editor working in libraries.

[bradenmacdonald]

@kdmccormick I could backport a more targeted PR to Teak. i.e. instead of this refactor ("don't pass it in to Editor from three places; check it in Editor"), I can just "pass it in to Editor from Library page too".

[kdmccormick]

@bradenmacdonald That would be great!

[open-craft-grove]

Sandbox deployment failed 💥
Please check the settings and requirements.
Retry deployment by pushing a new commit or updating the requirements/settings in the pull request's description.
📜 Failure Logs
ℹ️ Grove Config, Tutor Config, Tutor Requirements

[bradenmacdonald]

I could backport a more targeted PR to Teak. i.e. instead of this refactor ("don't pass it in to Editor from three places; check it in Editor"), I can just "pass it in to Editor from Library page too".

Backport: #2098

But I think it's blocked on #2099 and I'm not sure who will take that fix on, so for now it's just indefinitely on hold.