Function verifyCacheExpiration

internal/cache/content_cache_test.go:93–150

The test will fetch 4 items into the cache, named "a", "b", "c", "d", each 4000 bytes in size verify that the cache is evicting correct items based on the sweep settings. nolint:thelper

(t *testing.T, sweepSettings cache.SweepSettings, wantEvicted []blob.ID)

//
//nolint:thelper
func verifyCacheExpiration(t *testing.T, sweepSettings cache.SweepSettings, wantEvicted []blob.ID) {
	cacheData := blobtesting.DataMap{}

	// on Windows, the time does not always move forward (sometimes clock.Now() returns exactly the same value for consecutive invocations)
	// this matters here so we return a fake clock.Now() function that always moves forward.
	var currentTimeMutex sync.Mutex

	currentTime := clock.Now()

	movingTimeFunc := func() time.Time {
		currentTimeMutex.Lock()
		defer currentTimeMutex.Unlock()

		currentTime = currentTime.Add(1 * time.Millisecond)

		return currentTime
	}

	cacheStorage := testutil.EnsureType[cache.Storage](t, blobtesting.NewMapStorage(cacheData, nil, movingTimeFunc))
	underlyingStorage := newUnderlyingStorageForContentCacheTesting(t)

	ctx := testlogging.Context(t)
	cc, err := cache.NewContentCache(ctx, underlyingStorage, cache.Options{
		Storage: cacheStorage,
		Sweep:   sweepSettings,
		TimeNow: movingTimeFunc,
	}, nil)

	require.NoError(t, err)

	defer cc.Close(ctx)

	var tmp gather.WriteBuffer
	defer tmp.Close()

	const underlyingBlobID = "content-4k"

	err = cc.GetContent(ctx, "a", underlyingBlobID, 0, -1, &tmp) // 4k
	require.NoError(t, err)
	err = cc.GetContent(ctx, "b", underlyingBlobID, 0, -1, &tmp) // 4k
	require.NoError(t, err)
	err = cc.GetContent(ctx, "c", underlyingBlobID, 0, -1, &tmp) // 4k
	require.NoError(t, err)
	err = cc.GetContent(ctx, "d", underlyingBlobID, 0, -1, &tmp) // 4k
	require.NoError(t, err)

	// delete underlying storage blob to identify cache items that have been evicted
	// all other items will be fetched from the cache.
	require.NoError(t, underlyingStorage.DeleteBlob(ctx, underlyingBlobID))

	for _, blobID := range []blob.ID{"a", "b", "c", "d"} {
		if slices.Contains(wantEvicted, blobID) {
			require.ErrorIs(t, cc.GetContent(ctx, string(blobID), underlyingBlobID, 0, -1, &tmp), blob.ErrBlobNotFound, "expected item not found %v", blobID)
		} else {
			require.NoError(t, cc.GetContent(ctx, string(blobID), underlyingBlobID, 0, -1, &tmp), "expected item to be found %v", blobID)
		}
	}
}