Force FGS notifications to show for a minimum timeandroid-9.0.0_r51

It's possible for a service to do a start/stop foreground and cause a
couple of things to happen:

NotificationManagerService will enqueue a EnqueueNotificationRunnable,
post a PostNotificationRunnable (for the startForeground), and then also
enqueue a CancelNotificationRunnable. There is some racy behavior here
in that the cancel runnable can get triggered in between enqueue and
post runnables. If the cancel happens first, then
NotificationListenerServices will never get the message.

This behavior is technically allowed, however for foreground services we
want to ensure that there is a minmum amount of time that notification
listeners are aware of the foreground service so that (for instance) the
FGS notification can be shown.

This CL does two things to mitigate this problem:

1. Introduce checking in the CancelNotificationRunnable such that it
will not cancel until after PostNotificationRunnable has finished
executing.

2. Introduce a NotificationLifetimeExtender method that will allow a
lifetime extender to manage the lifetime of a notification that has been
enqueued but not inflated yet.

Bug: 119041698
Test: atest NotificationManagerServiceTest
Test: atest ForegroundServiceLifetimeExtenderTest
Change-Id: I0680034ed9315aa2c05282524d48faaed066ebd0
Merged-In: I0680034ed9315aa2c05282524d48faaed066ebd0
(cherry picked from commit 3b8c4743f630dcd370bfc5dc9683b551983fbe28)

7 files changed, 377 insertions, 3 deletions

diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/ForegroundServiceLifetimeExtender.java b/packages/SystemUI/src/com/android/systemui/statusbar/ForegroundServiceLifetimeExtender.java
new file mode 100644
index 000000000000..c1a06a2efc49
--- /dev/null
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/ForegroundServiceLifetimeExtender.java
@@ -0,0 +1,89 @@
+/*
+ * Copyright (C) 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.systemui.statusbar;
+
+import android.annotation.NonNull;
+import android.app.Notification;
+import android.os.Handler;
+import android.os.Looper;
+import android.util.ArraySet;
+
+import com.android.internal.annotations.VisibleForTesting;
+import com.android.systemui.statusbar.NotificationData;
+
+/**
+ * Extends the lifetime of foreground notification services such that they show for at least
+ * five seconds
+ */
+public class ForegroundServiceLifetimeExtender implements NotificationLifetimeExtender {
+
+    private static final String TAG = "FGSLifetimeExtender";
+    @VisibleForTesting
+    static final int MIN_FGS_TIME_MS = 5000;
+
+    private NotificationSafeToRemoveCallback mNotificationSafeToRemoveCallback;
+    private ArraySet<NotificationData.Entry> mManagedEntries = new ArraySet<>();
+    private Handler mHandler = new Handler(Looper.getMainLooper());
+
+    ForegroundServiceLifetimeExtender() {
+    }
+
+    @Override
+    public void setCallback(@NonNull NotificationSafeToRemoveCallback callback) {
+        mNotificationSafeToRemoveCallback = callback;
+    }
+
+    @Override
+    public boolean shouldExtendLifetime(@NonNull NotificationData.Entry entry) {
+        if ((entry.notification.getNotification().flags
+                & Notification.FLAG_FOREGROUND_SERVICE) == 0) {
+            return false;
+        }
+
+        long currentTime = System.currentTimeMillis();
+        return currentTime - entry.notification.getPostTime() < MIN_FGS_TIME_MS;
+    }
+
+    @Override
+    public boolean shouldExtendLifetimeForPendingNotification(
+            @NonNull NotificationData.Entry entry) {
+        return shouldExtendLifetime(entry);
+    }
+
+    @Override
+    public void setShouldManageLifetime(
+            @NonNull NotificationData.Entry entry, boolean shouldManage) {
+        if (!shouldManage) {
+            mManagedEntries.remove(entry);
+            return;
+        }
+
+        mManagedEntries.add(entry);
+
+        Runnable r = () -> {
+            if (mManagedEntries.contains(entry)) {
+                mManagedEntries.remove(entry);
+                if (mNotificationSafeToRemoveCallback != null) {
+                    mNotificationSafeToRemoveCallback.onSafeToRemove(entry.key);
+                }
+            }
+        };
+        long delayAmt = MIN_FGS_TIME_MS
+                - (System.currentTimeMillis() - entry.notification.getPostTime());
+        mHandler.postDelayed(r, delayAmt);
+    }
+}
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/NotificationEntryManager.java b/packages/SystemUI/src/com/android/systemui/statusbar/NotificationEntryManager.java
index 06f26c9cbc7c..148be512c5b7 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/NotificationEntryManager.java
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/NotificationEntryManager.java
@@ -38,6 +38,7 @@ import android.service.notification.NotificationStats;
 import android.service.notification.StatusBarNotification;
 import android.text.TextUtils;
 import android.util.ArraySet;
+import android.util.ArrayMap;
 import android.util.EventLog;
 import android.util.Log;
 import android.view.View;
@@ -71,6 +72,7 @@ import java.io.PrintWriter;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;
+import java.util.Map;
 
 /**
  * NotificationEntryManager is responsible for the adding, removing, and updating of notifications.
@@ -116,6 +118,12 @@ public class NotificationEntryManager implements Dumpable, NotificationInflater.
     private final SmartReplyController mSmartReplyController =
             Dependency.get(SmartReplyController.class);
 
+    // A lifetime extender that watches for foreground service notifications
+    private final NotificationLifetimeExtender mFGSExtender =
+            new ForegroundServiceLifetimeExtender();
+    private final Map<NotificationData.Entry, NotificationLifetimeExtender> mRetainedNotifications =
+            new ArrayMap<>();
+
     protected IStatusBarService mBarService;
     protected NotificationPresenter mPresenter;
     protected Callback mCallback;
@@ -227,6 +235,16 @@ public class NotificationEntryManager implements Dumpable, NotificationInflater.
                 pw.println(entry.notification);
             }
         }
+        pw.println("  Lifetime-extended notifications:");
+        if (mRetainedNotifications.isEmpty()) {
+            pw.println("    None");
+        } else {
+            for (Map.Entry<NotificationData.Entry, NotificationLifetimeExtender> entry
+                    : mRetainedNotifications.entrySet()) {
+                pw.println("    " + entry.getKey().notification + " retained by "
+                        + entry.getValue().getClass().getName());
+            }
+        }
         pw.print("  mUseHeadsUp=");
         pw.println(mUseHeadsUp);
         pw.print("  mKeysKeptForRemoteInput: ");
@@ -241,6 +259,7 @@ public class NotificationEntryManager implements Dumpable, NotificationInflater.
         mMessagingUtil = new NotificationMessagingUtil(context);
         mSystemServicesProxy = SystemServicesProxy.getInstance(mContext);
         mGroupManager.setPendingEntries(mPendingNotifications);
+        mFGSExtender.setCallback(key -> removeNotification(key, mLatestRankingMap));
     }
 
     public void setUpWithPresenter(NotificationPresenter presenter,
@@ -289,6 +308,12 @@ public class NotificationEntryManager implements Dumpable, NotificationInflater.
         mOnAppOpsClickListener = mGutsManager::openGuts;
     }
 
+    @VisibleForTesting
+    protected Map<NotificationData.Entry, NotificationLifetimeExtender>
+    getRetainedNotificationMap() {
+        return mRetainedNotifications;
+    }
+
     public NotificationData getNotificationData() {
         return mNotificationData;
     }
@@ -474,8 +499,17 @@ public class NotificationEntryManager implements Dumpable, NotificationInflater.
 
     @Override
     public void removeNotification(String key, NotificationListenerService.RankingMap ranking) {
-        boolean deferRemoval = false;
+        // First chance to extend the lifetime of a notification
+        NotificationData.Entry pendingEntry = mPendingNotifications.get(key);
+        if (pendingEntry != null) {
+            if (mFGSExtender.shouldExtendLifetimeForPendingNotification(pendingEntry)) {
+                extendLifetime(pendingEntry, mFGSExtender);
+                return;
+            }
+        }
+
         abortExistingInflation(key);
+        boolean deferRemoval = false;
         if (mHeadsUpManager.isHeadsUp(key)) {
             // A cancel() in response to a remote input shouldn't be delayed, as it makes the
             // sending look longer than it takes.
@@ -534,6 +568,11 @@ public class NotificationEntryManager implements Dumpable, NotificationInflater.
             }
         }
 
+        if (entry != null && mFGSExtender.shouldExtendLifetime(entry)) {
+            extendLifetime(entry, mFGSExtender);
+            return;
+        }
+
         // Actually removing notification so smart reply controller can forget about it.
         mSmartReplyController.stopSending(entry);
 
@@ -569,9 +608,30 @@ public class NotificationEntryManager implements Dumpable, NotificationInflater.
         handleGroupSummaryRemoved(key);
         StatusBarNotification old = removeNotificationViews(key, ranking);
 
+        // Make sure no lifetime extension is happening anymore
+        cancelLifetimeExtension(entry);
         mCallback.onNotificationRemoved(key, old);
     }
 
+    private void extendLifetime(
+            NotificationData.Entry entry, NotificationLifetimeExtender extender) {
+        // Cancel any other extender which might be holding on to this notification entry
+        NotificationLifetimeExtender activeExtender = mRetainedNotifications.get(entry);
+        if (activeExtender != null && activeExtender != extender) {
+            activeExtender.setShouldManageLifetime(entry, false);
+        }
+
+        mRetainedNotifications.put(entry, extender);
+        extender.setShouldManageLifetime(entry, true);
+    }
+
+    private void cancelLifetimeExtension(NotificationData.Entry entry) {
+        NotificationLifetimeExtender activeExtender = mRetainedNotifications.remove(entry);
+        if (activeExtender != null) {
+            activeExtender.setShouldManageLifetime(entry, false);
+        }
+    }
+
     public StatusBarNotification rebuildNotificationWithRemoteInput(NotificationData.Entry entry,
             CharSequence remoteInputText, boolean showSpinner) {
         StatusBarNotification sbn = entry.notification;
@@ -855,6 +915,9 @@ public class NotificationEntryManager implements Dumpable, NotificationInflater.
             Log.w(TAG, "Notification that was kept for guts was updated. " + key);
         }
 
+        // No need to keep the lifetime extension around if an update comes in
+        cancelLifetimeExtension(entry);
+
         Notification n = notification.getNotification();
         mNotificationData.updateRanking(ranking);
 
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/NotificationLifetimeExtender.java b/packages/SystemUI/src/com/android/systemui/statusbar/NotificationLifetimeExtender.java
new file mode 100644
index 000000000000..96cfab7aeec9
--- /dev/null
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/NotificationLifetimeExtender.java
@@ -0,0 +1,65 @@
+package com.android.systemui.statusbar;
+
+import android.annotation.NonNull;
+
+import com.android.systemui.statusbar.NotificationData;
+
+/**
+ * Interface for anything that may need to keep notifications managed even after
+ * {@link NotificationListener} removes it.  The lifetime extender is in charge of performing the
+ * callback when the notification is then safe to remove.
+ */
+public interface NotificationLifetimeExtender {
+
+    /**
+     * Set the handler to callback to when the notification is safe to remove.
+     *
+     * @param callback the handler to callback
+     */
+    void setCallback(@NonNull NotificationSafeToRemoveCallback callback);
+
+    /**
+     * Determines whether or not the extender needs the notification kept after removal.
+     *
+     * @param entry the entry containing the notification to check
+     * @return true if the notification lifetime should be extended
+     */
+    boolean shouldExtendLifetime(@NonNull NotificationData.Entry entry);
+
+    /**
+     * It's possible that a notification was canceled before it ever became visible. This callback
+     * gives lifetime extenders a chance to make sure it shows up. For example if a foreground
+     * service is canceled too quickly but we still want to make sure a FGS notification shows.
+     * @param pendingEntry the canceled (but pending) entry
+     * @return true if the notification lifetime should be extended
+     */
+    default boolean shouldExtendLifetimeForPendingNotification(
+            @NonNull NotificationData.Entry pendingEntry) {
+        return false;
+    }
+
+    /**
+     * Sets whether or not the lifetime should be managed by the extender.  In practice, if
+     * shouldManage is true, this is where the extender starts managing the entry internally and is
+     * now responsible for calling {@link NotificationSafeToRemoveCallback#onSafeToRemove(String)}
+     * when the entry is safe to remove.  If shouldManage is false, the extender no longer needs to
+     * worry about it (either because we will be removing it anyway or the entry is no longer
+     * removed due to an update).
+     *
+     * @param entry the entry that needs an extended lifetime
+     * @param shouldManage true if the extender should manage the entry now, false otherwise
+     */
+    void setShouldManageLifetime(@NonNull NotificationData.Entry entry, boolean shouldManage);
+
+    /**
+     * The callback for when the notification is now safe to remove (i.e. its lifetime has ended).
+     */
+    interface NotificationSafeToRemoveCallback {
+        /**
+         * Called when the lifetime extender determines it's safe to remove.
+         *
+         * @param key key of the entry that is now safe to remove
+         */
+        void onSafeToRemove(String key);
+    }
+}
diff --git a/packages/SystemUI/tests/src/com/android/systemui/statusbar/ForegroundServiceLifetimeExtenderTest.java b/packages/SystemUI/tests/src/com/android/systemui/statusbar/ForegroundServiceLifetimeExtenderTest.java
new file mode 100644
index 000000000000..daf2f95b1f98
--- /dev/null
+++ b/packages/SystemUI/tests/src/com/android/systemui/statusbar/ForegroundServiceLifetimeExtenderTest.java
@@ -0,0 +1,88 @@
+/*
+ * Copyright (C) 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.systemui.statusbar;
+
+import static com.android.systemui.statusbar.ForegroundServiceLifetimeExtender.MIN_FGS_TIME_MS;
+
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+
+import android.app.Notification;
+import android.service.notification.NotificationListenerService.Ranking;
+import android.service.notification.StatusBarNotification;
+
+import android.support.test.filters.SmallTest;
+import android.support.test.runner.AndroidJUnit4;
+
+import com.android.systemui.R;
+import com.android.systemui.SysuiTestCase;
+import com.android.systemui.statusbar.NotificationData.Entry;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+@RunWith(AndroidJUnit4.class)
+@SmallTest
+public class ForegroundServiceLifetimeExtenderTest extends SysuiTestCase {
+    private ForegroundServiceLifetimeExtender mExtender = new ForegroundServiceLifetimeExtender();
+    private StatusBarNotification mSbn;
+    private NotificationData.Entry mEntry;
+    private Notification mNotif;
+
+    @Before
+    public void setup() {
+        mNotif = new Notification.Builder(mContext, "")
+                .setSmallIcon(R.drawable.ic_person)
+                .setContentTitle("Title")
+                .setContentText("Text")
+                .build();
+
+        mSbn = mock(StatusBarNotification.class);
+        when(mSbn.getNotification()).thenReturn(mNotif);
+
+        mEntry = new NotificationData.Entry(mSbn);
+    }
+
+    /**
+     * ForegroundServiceLifetimeExtenderTest
+     */
+    @Test
+    public void testShouldExtendLifetime_should_foreground() {
+        // Extend the lifetime of a FGS notification iff it has not been visible
+        // for the minimum time
+        mNotif.flags |= Notification.FLAG_FOREGROUND_SERVICE;
+        when(mSbn.getPostTime()).thenReturn(System.currentTimeMillis());
+        assertTrue(mExtender.shouldExtendLifetime(mEntry));
+    }
+
+    @Test
+    public void testShouldExtendLifetime_shouldNot_foreground() {
+        mNotif.flags |= Notification.FLAG_FOREGROUND_SERVICE;
+        when(mSbn.getPostTime()).thenReturn(System.currentTimeMillis() - MIN_FGS_TIME_MS - 1);
+        assertFalse(mExtender.shouldExtendLifetime(mEntry));
+    }
+
+    @Test
+    public void testShouldExtendLifetime_shouldNot_notForeground() {
+        mNotif.flags = 0;
+        when(mSbn.getPostTime()).thenReturn(System.currentTimeMillis() - MIN_FGS_TIME_MS - 1);
+        assertFalse(mExtender.shouldExtendLifetime(mEntry));
+    }
+}
\ No newline at end of file
diff --git a/packages/SystemUI/tests/src/com/android/systemui/statusbar/NotificationEntryManagerTest.java b/packages/SystemUI/tests/src/com/android/systemui/statusbar/NotificationEntryManagerTest.java
index afe16cf13b76..69db4b5fa86d 100644
--- a/packages/SystemUI/tests/src/com/android/systemui/statusbar/NotificationEntryManagerTest.java
+++ b/packages/SystemUI/tests/src/com/android/systemui/statusbar/NotificationEntryManagerTest.java
@@ -16,6 +16,8 @@
 
 package com.android.systemui.statusbar;
 
+import static com.android.systemui.statusbar.ForegroundServiceLifetimeExtender.MIN_FGS_TIME_MS;
+
 import static junit.framework.Assert.assertNotNull;
 import static junit.framework.Assert.assertNull;
 import static junit.framework.Assert.assertTrue;
@@ -54,11 +56,13 @@ import com.android.internal.statusbar.IStatusBarService;
 import com.android.systemui.ForegroundServiceController;
 import com.android.systemui.R;
 import com.android.systemui.SysuiTestCase;
+import com.android.systemui.statusbar.NotificationData.Entry;
 import com.android.systemui.statusbar.notification.VisualStabilityManager;
 import com.android.systemui.statusbar.phone.NotificationGroupManager;
 import com.android.systemui.statusbar.policy.DeviceProvisionedController;
 import com.android.systemui.statusbar.policy.HeadsUpManager;
 
+import java.util.Map;
 import junit.framework.Assert;
 
 import org.junit.Before;
@@ -427,4 +431,48 @@ public class NotificationEntryManagerTest extends SysuiTestCase {
         Assert.assertTrue(newSbn.getNotification().extras
                 .getBoolean(Notification.EXTRA_HIDE_SMART_REPLIES, false));
     }
+
+    @Test
+    public void testForegroundServiceNotificationKeptForFiveSeconds() {
+        // sbn posted "just now"
+        Notification n = new Notification.Builder(mContext, "")
+                .setSmallIcon(R.drawable.ic_person)
+                .setContentTitle("Title")
+                .setContentText("Text")
+                .build();
+        n.flags |= Notification.FLAG_FOREGROUND_SERVICE;
+        mSbn = new StatusBarNotification(TEST_PACKAGE_NAME, TEST_PACKAGE_NAME, 0, null, TEST_UID,
+                0, n, new UserHandle(ActivityManager.getCurrentUser()), null,
+                System.currentTimeMillis());
+        mEntry = new Entry(mSbn);
+        mEntryManager.getNotificationData().add(mEntry);
+        mEntryManager.removeNotification(mEntry.key, mRankingMap);
+
+        Map<NotificationData.Entry, NotificationLifetimeExtender> map =
+                mEntryManager.getRetainedNotificationMap();
+
+        Assert.assertTrue(map.containsKey(mEntry));
+    }
+
+    @Test
+    public void testForegroundServiceNotification_notRetainedIfShownForFiveSeconds() {
+        // sbn posted "more than 5 seconds ago"
+        Notification n = new Notification.Builder(mContext, "")
+                .setSmallIcon(R.drawable.ic_person)
+                .setContentTitle("Title")
+                .setContentText("Text")
+                .build();
+        n.flags |= Notification.FLAG_FOREGROUND_SERVICE;
+        mSbn = new StatusBarNotification(TEST_PACKAGE_NAME, TEST_PACKAGE_NAME, 0, null, TEST_UID,
+                0, n, new UserHandle(ActivityManager.getCurrentUser()), null,
+                System.currentTimeMillis() - MIN_FGS_TIME_MS - 1);
+        mEntry = new Entry(mSbn);
+        mEntryManager.getNotificationData().add(mEntry);
+        mEntryManager.removeNotification(mEntry.key, mRankingMap);
+
+        Map<NotificationData.Entry, NotificationLifetimeExtender> map =
+                mEntryManager.getRetainedNotificationMap();
+
+        Assert.assertFalse(map.containsKey(mEntry));
+    }
 }
diff --git a/services/core/java/com/android/server/notification/NotificationManagerService.java b/services/core/java/com/android/server/notification/NotificationManagerService.java
index dfcbf0524c5d..897877ad729f 100644
--- a/services/core/java/com/android/server/notification/NotificationManagerService.java
+++ b/services/core/java/com/android/server/notification/NotificationManagerService.java
@@ -5658,8 +5658,15 @@ public class NotificationManagerService extends SystemService {
                         userId, mustHaveFlags, mustNotHaveFlags, reason, listenerName);
 
                 synchronized (mNotificationLock) {
-                    // Look for the notification, searching both the posted and enqueued lists.
-                    NotificationRecord r = findNotificationLocked(pkg, tag, id, userId);
+                    // If the notification is currently enqueued, repost this runnable so it has a
+                    // chance to notify listeners
+                    if ((findNotificationByListLocked(
+                            mEnqueuedNotifications, pkg, tag, id, userId)) != null) {
+                        mHandler.post(this);
+                    }
+                    // Look for the notification in the posted list, since we already checked enq
+                    NotificationRecord r = findNotificationByListLocked(
+                            mNotificationList, pkg, tag, id, userId);
                     if (r != null) {
                         // The notification was found, check if it should be removed.
 
diff --git a/services/tests/uiservicestests/src/com/android/server/notification/NotificationManagerServiceTest.java b/services/tests/uiservicestests/src/com/android/server/notification/NotificationManagerServiceTest.java
index 3446c16cb32b..8b719de98f04 100644
--- a/services/tests/uiservicestests/src/com/android/server/notification/NotificationManagerServiceTest.java
+++ b/services/tests/uiservicestests/src/com/android/server/notification/NotificationManagerServiceTest.java
@@ -708,6 +708,20 @@ public class NotificationManagerServiceTest extends UiServiceTestCase {
     }
 
     @Test
+    public void testCancelImmediatelyAfterEnqueueNotifiesListeners_ForegroundServiceFlag()
+            throws Exception {
+        final StatusBarNotification sbn = generateNotificationRecord(null).sbn;
+        sbn.getNotification().flags =
+                Notification.FLAG_ONGOING_EVENT | FLAG_FOREGROUND_SERVICE;
+        mBinderService.enqueueNotificationWithTag(PKG, "opPkg", "tag",
+                sbn.getId(), sbn.getNotification(), sbn.getUserId());
+        mBinderService.cancelNotificationWithTag(PKG, "tag", sbn.getId(), sbn.getUserId());
+        waitForIdle();
+        verify(mListeners, times(1)).notifyPostedLocked(any(), any());
+        verify(mListeners, times(1)).notifyRemovedLocked(any(), anyInt(), any());
+    }
+
+    @Test
     public void testUserInitiatedClearAll_noLeak() throws Exception {
         final NotificationRecord n = generateNotificationRecord(
                 mTestNotificationChannel, 1, "group", true);