InfoTab: Add caching for namespace details

[skoeva]

The InfoTab was making two sequential Azure CLI calls on every open, causing ~1 minute load times. This change replaces that with a single fetch backed by a module-level cache so subsequent opens are instant.

Fixes: #280

Summary

• Removed the redundant getManagedNamespaces list call - getManagedNamespacesDetails is now called directly
• Added a module-level detailsCache (stale-while-revalidate): cached data is shown immediately, a background fetch keeps it fresh
• Cache is invalidated after a successful save so stale data is never shown post-update
• Added handleRefresh for manual re-fetches and a revalidating state for background fetch indication
• Updated InfoTab.tsx to show a background spinner and a Refresh button
• Updated tests: removed obsolete getManagedNamespaces mock/cases, added coverage for cache hit, background revalidation, error suppression with cached data, and cache invalidation on save

Testing

• Run cd plugins/aks-desktop && npm test and ensure the tests pass

[Copilot]

Pull request overview

Improves the AKS Desktop Project Info tab load time by switching namespace-details fetching to a single Azure CLI call and adding a stale-while-revalidate, module-level cache so subsequent tab opens are fast while still revalidating in the background.

Changes:

• Removed the extra “list managed namespaces” Azure CLI call and fetches namespace details directly.
• Added a module-level cache with background revalidation + manual refresh + cache invalidation after save.
• Updated the InfoTab UI (background refresh indicator + Refresh button) and adjusted tests accordingly.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 6 comments.

File	Description
plugins/aks-desktop/src/components/InfoTab/hooks/useInfoTab.ts	Implements module-level caching, background revalidation, refresh handler, and cache invalidation on save.
plugins/aks-desktop/src/components/InfoTab/InfoTab.tsx	Adds UI affordances for background refresh status and a Refresh button.
plugins/aks-desktop/src/components/InfoTab/hooks/useInfoTab.test.ts	Updates hook tests for caching/revalidation behavior and removes obsolete mocks.

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[Copilot]

detailsCache is keyed only by ${clusterName}/${projectId}, but the Azure CLI call is also scoped by resourceGroup (and optionally subscriptionId). If two clusters share a name across subscriptions/resource groups, or a project ID repeats, the cache can serve details for the wrong Azure resource. Consider incorporating resourceGroup and subscriptionId into the cache key (and keep the comment above the cache in sync).

Suggested change

	const cacheKey = clusterName && projectId ? `${clusterName}/${projectId}` : null;
	const cacheKey =
	clusterName && projectId && resourceGroup && subscription
	? `${subscription}/${resourceGroup}/${clusterName}/${projectId}`
	: null;

[Copilot]

The module-level cache is exported as a mutable Map “for testing only”, which makes it part of the public module surface area in production and allows unintended writes from other imports. Prefer keeping the Map private and exporting a small test helper (e.g., clearDetailsCache() / getDetailsCacheForTests()), similar to other caches in the repo.

Suggested change

	// Exported for testing purposes only.
	export const detailsCache = new Map<string, NamespaceDetails>();
	// Kept private; use the exported helpers below for tests.
	const detailsCache = new Map<string, NamespaceDetails>();
	// Test helpers: narrow surface for accessing the module-level cache.
	export function clearDetailsCacheForTests(): void {
	detailsCache.clear();
	}
	export function getDetailsCacheForTests(): ReadonlyMap<string, NamespaceDetails> {
	return detailsCache;
	}

[Copilot]

When resourceGroup is temporarily unavailable (e.g., first render before Namespace.useGet resolves), this effect clears namespaceDetails to null even if cached data was available, causing the UI to briefly show cached content and then blank out. Consider not clearing namespaceDetails when cached data exists; instead, skip the CLI fetch until resourceGroup is known while continuing to display cached data.

Suggested change

	setLoading(false);
	setError(null);
	setNamespaceDetails(null);
	// We don't have enough information to fetch yet. Avoid clearing
	// any existing namespaceDetails so cached data can continue to show.
	setLoading(false);
	setError(null);

[Copilot]

handleRefresh deletes the cache entry before triggering a refetch. This makes the subsequent fetch behave like a cold start (sets loading instead of revalidating), which will hide the form and show the full-page spinner rather than keeping existing data visible while refreshing. Consider keeping the existing cached/state data and using refreshTick to force a revalidation fetch (or treating refresh as revalidation even if the cache is cleared).

Suggested change

	if (cacheKey) detailsCache.delete(cacheKey);
	setRefreshTick(n => n + 1);
	}, [cacheKey]);
	// Trigger a revalidation fetch while keeping existing cached/state data,
	// so the UI stays on the form and shows a background refresh instead of a cold-start spinner.
	setRefreshTick(n => n + 1);
	}, []);

[Copilot]

This new i18n key (Refreshing data in background) is not present in the repo locale files, so users will see the raw English key (and localization consistency checks may fail). Add it to plugins/aks-desktop/locales/*/translation.json (or switch to an existing key if one already conveys the same meaning).

Suggested change

	<Tooltip title={t('Refreshing data in background')}>
	<Tooltip title="Refreshing data in background">

[Copilot]

This test waits on revalidating to become false after calling handleRefresh, but handleRefresh currently clears the cache which makes the next fetch use the loading path (so revalidating may remain false throughout). That means the test may assert toHaveBeenCalledTimes(2) before the second effect-driven fetch actually runs. Prefer waiting for mockGetManagedNamespaceDetails to reach 2 calls (or for loading to return to false) to make the test deterministic.

Suggested change

	await waitFor(() => expect(result.current.revalidating).toBe(false));
	expect(mockGetManagedNamespaceDetails).toHaveBeenCalledTimes(2);
	await waitFor(() =>
	expect(mockGetManagedNamespaceDetails).toHaveBeenCalledTimes(2)
	);