Bug/form data caching

[olemartinorg]

Description

One-liner fix with some more baggage.. This sets gcTime: 0 on all form data queries, not just the stateless ones. Debugging this made me scratch my head more than usual, but what I observed was:

• The model was fetched early (as soon as it became visible in the instance data) by FormDataReaders (so, because it was being references in a text resource). Thus, some data was added to the query cache.
• When calling process/next, the content in the data model was expanded in a TaskEnd hook on the backend.
• When entering Task_2 on the frontend, even though we called invalidateFormDataQueries(), the stale query result from before re-appeared in the query cache and was used to bootstrap the new FormDataWrite with old data.

I spent some time building a whole new cache-busting mechanism using the lastChanged property from the instance data, but that didn't do anything - it took me a while to notice we already cleared the form data query cache.

Also, for some reason this all works fine if Task_1 has a component that references the data model, so the bug depended on FormDataReaders being the one to fetch the data model for some reason.

Related Issue(s)

• closes Ekstra modeller blir ikke lastet opp til data task ved task start. #3634

Verification/QA

• Manual functionality testing
  • I have tested these changes manually
  • Creator of the original issue (or service owner) has been contacted for manual testing (or will be contacted when released in alpha)
  • No testing done/necessary
• Automated tests
  • Unit test(s) have been added/updated
  • Cypress E2E test(s) have been added/updated
  • No automatic tests are needed here (no functional changes/additions)
  • I want someone to help me make some tests
• UU/WCAG (follow these guidelines until we have our own)
  • I have tested with a screen reader/keyboard navigation/automated wcag validator
  • No testing done/necessary (no DOM/visual changes)
  • I want someone to help me perform accessibility testing
• User documentation @ altinn-studio-docs
  • Has been added/updated
  • No functionality has been changed/added, so no documentation is needed
  • I will do that later/have created an issue
• Support in Altinn Studio
  • Issue(s) created for support in Studio
  • This change/feature does not require any changes to Altinn Studio
• Sprint board
  • The original issue (or this PR itself) has been added to the Team Apps project and to the current sprint board
  • I don't have permissions to do that, please help me out
• Labels
  • I have added a kind/* and backport* label to this PR for proper release notes grouping
  • I don't have permissions to add labels, please help me out

Summary by CodeRabbit

• Bug Fixes

  • Improved handling of cached data across form navigation to prevent stale query results.

• Tests

  • Added end-to-end test to verify data model caching works correctly across task transitions.
  • Updated existing test validation assertions.

_{✏️ Tip: You can customize this high-level summary in your review settings.}

[coderabbitai]

📝 Walkthrough

Walkthrough

This change addresses issue #3634 by simplifying form data query caching behavior. A stateless app conditional path is removed from useFormDataQuery, unifying cache handling to consistently apply gcTime: 0 and refetchInterval: false across all application states. New and updated tests verify that multiple data models load correctly without stale data interference.

Changes

Cohort / File(s)	Summary
Form Data Query Logic src/features/formData/useFormDataQuery.tsx	Removed conditional branching based on isStatelessApp flag. Early return path eliminated; cache configuration now unified with gcTime: 0 and refetchInterval: false applied uniformly. Function signatures unchanged.
Multiple Data Models Tests test/e2e/integration/multiple-datamodels-test/fetching.ts	New regression test for issue #3634. Verifies multiple data models load and remain correct across task navigation, data binding inspection, response delay scenarios, and form submission without validation errors.
Multiple Data Models Tests test/e2e/integration/multiple-datamodels-test/readonly.ts	Updated heading assertion after task navigation from case-insensitive match to exact text match.

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~22 minutes

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title 'Bug/form data caching' is directly related to the main change: fixing form data caching behavior by setting gcTime: 0 on all form data queries to prevent stale cached data.
Description check	✅ Passed	The PR description is comprehensive and well-structured, covering the bug explanation, root cause analysis, solution approach, related issue link, and detailed verification checklist with relevant items checked.
Linked Issues check	✅ Passed	The PR fully addresses issue #3634 by fixing the root cause where form data models were not loaded at task start due to stale cached query results. The one-line fix (gcTime: 0) prevents cache persistence, and E2E tests verify the fix resolves the scenario described in the issue.
Out of Scope Changes check	✅ Passed	All changes are scoped to the form data caching issue: the core fix in useFormDataQuery.tsx, a new E2E test reproducing issue #3634, and a minor test assertion update in readonly.ts related to the same regression context.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ Finishing touches

• 📝 Generate docstrings

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Post copyable unit tests in a comment
• Commit unit tests in branch bug/form-data-caching

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[github-actions]

✅ Automatic backport successful!

A backport PR has been automatically created for the release/v4.25 release branch.

The release branch release/v4.25 already existed and was updated.

The cherry-pick was clean with no conflicts. Please review the backport PR when it appears.