Limit number of previews held in AppWidgetService (e95aef8b) · Commits · e / os / android_frameworks_base

core/java/com/android/internal/config/sysui/SystemUiDeviceConfigFlags.java

+6 −0

Original line number	Diff line number	Diff line
		@@ -573,6 +573,12 @@ public final class SystemUiDeviceConfigFlags {
		public static final String GENERATED_PREVIEW_API_MAX_CALLS_PER_INTERVAL =
		"generated_preview_api_max_calls_per_interval";

		/*
		* (int) The max number of providers for which to keep generated previews.
		*/
		public static final String GENERATED_PREVIEW_API_MAX_PROVIDERS =
		"generated_preview_api_max_providers";

		private SystemUiDeviceConfigFlags() {
		}
		}

services/appwidget/java/com/android/server/appwidget/AppWidgetServiceImpl.java

+38 −14

Original line number	Diff line number	Diff line
		@@ -213,6 +213,8 @@ class AppWidgetServiceImpl extends IAppWidgetService.Stub implements WidgetBacku
		Duration.ofHours(1).toMillis();
		// Default max API calls per reset interval for generated preview API rate limiting.
		private static final int DEFAULT_GENERATED_PREVIEW_MAX_CALLS_PER_INTERVAL = 2;
		// Default max number of providers for which to keep previews.
		private static final int DEFAULT_GENERATED_PREVIEW_MAX_PROVIDERS = 50;
		// XML attribute for widget ids that are pending deletion.
		// See {@link Provider#pendingDeletedWidgetIds}.
		private static final String PENDING_DELETED_IDS_ATTR = "pending_deleted_ids";
		@@ -358,10 +360,13 @@ class AppWidgetServiceImpl extends IAppWidgetService.Stub implements WidgetBacku
		SystemUiDeviceConfigFlags.GENERATED_PREVIEW_API_RESET_INTERVAL_MS,
		DEFAULT_GENERATED_PREVIEW_RESET_INTERVAL_MS);
		final int generatedPreviewMaxCallsPerInterval = DeviceConfig.getInt(NAMESPACE_SYSTEMUI,
		SystemUiDeviceConfigFlags.GENERATED_PREVIEW_API_RESET_INTERVAL_MS,
		SystemUiDeviceConfigFlags.GENERATED_PREVIEW_API_MAX_CALLS_PER_INTERVAL,
		DEFAULT_GENERATED_PREVIEW_MAX_CALLS_PER_INTERVAL);
		final int generatedPreviewsMaxProviders = DeviceConfig.getInt(NAMESPACE_SYSTEMUI,
		SystemUiDeviceConfigFlags.GENERATED_PREVIEW_API_MAX_PROVIDERS,
		DEFAULT_GENERATED_PREVIEW_MAX_PROVIDERS);
		mGeneratedPreviewsApiCounter = new ApiCounter(generatedPreviewResetInterval,
		generatedPreviewMaxCallsPerInterval);
		generatedPreviewMaxCallsPerInterval, generatedPreviewsMaxProviders);
		DeviceConfig.addOnPropertiesChangedListener(NAMESPACE_SYSTEMUI,
		new HandlerExecutor(mCallbackHandler), this::handleSystemUiDeviceConfigChange);

		@@ -4660,6 +4665,13 @@ class AppWidgetServiceImpl extends IAppWidgetService.Stub implements WidgetBacku
		/* defaultValue= */ mGeneratedPreviewsApiCounter.getMaxCallsPerInterval());
		mGeneratedPreviewsApiCounter.setMaxCallsPerInterval(maxCallsPerInterval);
		}
		if (changed.contains(
		SystemUiDeviceConfigFlags.GENERATED_PREVIEW_API_MAX_PROVIDERS)) {
		int maxProviders = properties.getInt(
		SystemUiDeviceConfigFlags.GENERATED_PREVIEW_API_MAX_PROVIDERS,
		/* defaultValue= */ mGeneratedPreviewsApiCounter.getMaxProviders());
		mGeneratedPreviewsApiCounter.setMaxProviders(maxProviders);
		}
		}
		}

		@@ -5444,17 +5456,22 @@ class AppWidgetServiceImpl extends IAppWidgetService.Stub implements WidgetBacku
		private long mResetIntervalMs;
		// The max number of API calls per interval.
		private int mMaxCallsPerInterval;
		// The max number of providers to keep call records for. Any call to tryApiCall for new
		// providers will return false after this limit.
		private int mMaxProviders;

		// Returns the current time (monotonic). By default this is SystemClock.elapsedRealtime.
		private LongSupplier mMonotonicClock;

		ApiCounter(long resetIntervalMs, int maxCallsPerInterval) {
		this(resetIntervalMs, maxCallsPerInterval, SystemClock::elapsedRealtime);
		ApiCounter(long resetIntervalMs, int maxCallsPerInterval, int maxProviders) {
		this(resetIntervalMs, maxCallsPerInterval, maxProviders, SystemClock::elapsedRealtime);
		}

		ApiCounter(long resetIntervalMs, int maxCallsPerInterval,
		ApiCounter(long resetIntervalMs, int maxCallsPerInterval, int maxProviders,
		LongSupplier monotonicClock) {
		mResetIntervalMs = resetIntervalMs;
		mMaxCallsPerInterval = maxCallsPerInterval;
		mMaxProviders = maxProviders;
		mMonotonicClock = monotonicClock;
		}

		@@ -5474,12 +5491,27 @@ class AppWidgetServiceImpl extends IAppWidgetService.Stub implements WidgetBacku
		return mMaxCallsPerInterval;
		}

		public void setMaxProviders(int maxProviders) {
		mMaxProviders = maxProviders;
		}

		public int getMaxProviders() {
		return mMaxProviders;
		}

		/**
		* Returns true if the API call for the provider should be allowed, false if it should be
		* rate-limited.
		*/
		public boolean tryApiCall(@NonNull ProviderId provider) {
		final ApiCallRecord record = getOrCreateRecord(provider);
		if (!mCallCount.containsKey(provider)) {
		if (mCallCount.size() >= mMaxProviders) {
		return false;
		}
		mCallCount.put(provider, new ApiCallRecord());
		}
		ApiCallRecord record = mCallCount.get(provider);

		final long now = mMonotonicClock.getAsLong();
		final long timeSinceLastResetMs = now - record.lastResetTimeMs;
		// If the last reset was beyond the reset interval, reset now.
		@@ -5500,14 +5532,6 @@ class AppWidgetServiceImpl extends IAppWidgetService.Stub implements WidgetBacku
		public void remove(@NonNull ProviderId id) {
		mCallCount.remove(id);
		}

		@NonNull
		private ApiCallRecord getOrCreateRecord(@NonNull ProviderId provider) {
		if (!mCallCount.containsKey(provider)) {
		mCallCount.put(provider, new ApiCallRecord());
		}
		return mCallCount.get(provider);
		}
		}

		private class LoadedWidgetState {

services/tests/servicestests/src/com/android/server/appwidget/ApiCounterTest.kt

+20 −1

Original line number	Diff line number	Diff line
		@@ -25,6 +25,7 @@ class ApiCounterTest {
		private companion object {
		const val RESET_INTERVAL_MS = 10L
		const val MAX_CALLS_PER_INTERVAL = 2
		const val MAX_PROVIDERS = 10
		}

		private var currentTime = 0L
		@@ -34,7 +35,9 @@ class ApiCounterTest {
		/* uid= */ 123,
		ComponentName("com.android.server.appwidget", "FakeProviderClass")
		)
		private val counter = ApiCounter(RESET_INTERVAL_MS, MAX_CALLS_PER_INTERVAL) { currentTime }
		private val counter = ApiCounter(RESET_INTERVAL_MS, MAX_CALLS_PER_INTERVAL, MAX_PROVIDERS) {
		currentTime
		}

		@Test
		fun tryApiCall() {
		@@ -58,4 +61,20 @@ class ApiCounterTest {
		counter.remove(id)
		assertThat(counter.tryApiCall(id)).isTrue()
		}

		@Test
		fun maxProviders() {
		for (i in 0 until MAX_PROVIDERS) {
		for (j in 0 until MAX_CALLS_PER_INTERVAL) {
		assertThat(counter.tryApiCall(providerId(i))).isTrue()
		}
		}
		assertThat(counter.tryApiCall(providerId(MAX_PROVIDERS))).isFalse()
		// remove will allow another provider to be added
		counter.remove(providerId(0))
		assertThat(counter.tryApiCall(providerId(MAX_PROVIDERS))).isTrue()
		}

		private fun providerId(i: Int) =
		AppWidgetServiceImpl.ProviderId(/* uid= */ i, id.componentName)
		}