[Discover]Fix infinite loop cause discover hang

[Hailong-am]

Description

Fix an infinite loop cause discover hang.

OpenSearch-Dashboards/src/plugins/discover/public/application/view_components/utils/use_index_pattern.ts

Lines 47 to 66 in cedba8e

	const handleIndexPattern = async () => {
	if (isQueryEnhancementEnabled && query?.dataset) {
	const pattern = await data.indexPatterns.get(query.dataset.id);
	if (isMounted && pattern) {
	setIndexPattern(pattern);
	}
	} else if (!isQueryEnhancementEnabled) {
	if (!indexPatternIdFromState) {
	const indexPatternList = await data.indexPatterns.getCache();
	const newId = getIndexPatternId(
	'',
	indexPatternList || [],
	uiSettings.get('defaultIndex')
	);
	if (isMounted) {
	store!.dispatch(updateIndexPattern(newId));
	handleIndexPattern();
	}
	} else {

From the url below, we can see indexPattern is empty string. Based on the logic above,
http://localhost:5601/app/data-explorer/discover#?_a=(discover:(columns:!(_source),isDirty:!f,sort:!()),metadata:(indexPattern:'',view:discover))&_g=(filters:!(),refreshInterval:(pause:!t,value:0),time:(from:now-15m,to:now))

If newId is empty, indexPatternIdFromState will be empty string, when line 64 handleIndexPattern(); execute, it will go to same condition path and have infinite loop.

Issues Resolved

#7626

Screenshot

Testing the changes

Changelog

• fix: [Discover]Fix infinite loop cause discover hang

Check List

• All tests pass
  • yarn test:jest
  • yarn test:jest_integration
• New functionality includes testing.
• New functionality has been documented.
• Update CHANGELOG.md
• Commits are signed per the DCO using --signoff

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 1 line in your changes missing coverage. Please review.

Project coverage is 60.58%. Comparing base (dfc7def) to head (e81204f).
Report is 72 commits behind head on main.

Files with missing lines	Patch %	Lines
...ication/view_components/utils/use_index_pattern.ts	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #8082      +/-   ##
==========================================
- Coverage   60.58%   60.58%   -0.01%     
==========================================
  Files        3738     3738              
  Lines       88670    88670              
  Branches    13782    13782              
==========================================
- Hits        53725    53723       -2     
- Misses      31661    31662       +1     
- Partials     3284     3285       +1     

Flag	Coverage Δ
Linux_1	28.76% <0.00%> (ø)
Linux_2	56.27% <ø> (ø)
Linux_3	37.51% <0.00%> (-0.01%)	⬇️
Linux_4	29.61% <ø> (ø)
Windows_1	28.77% <0.00%> (ø)
Windows_2	56.22% <ø> (ø)
Windows_3	37.51% <0.00%> (ø)
Windows_4	29.61% <ø> (ø)

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