[BOT.3] Add unit test for polling network stats in the coordinator am:...

import androidx.annotation.NonNull;

import androidx.annotation.Nullable;

import com.android.internal.annotations.VisibleForTesting;

/**

 *  This coordinator is responsible for providing BPF offload relevant functionality.

 *  - Get tethering stats.

 */

public class BpfCoordinator {

    private static final String TAG = BpfCoordinator.class.getSimpleName();

    // TODO: Make it customizable.

    private static final int DEFAULT_PERFORM_POLL_INTERVAL_MS = 5000;

    @VisibleForTesting

    static final int DEFAULT_PERFORM_POLL_INTERVAL_MS = 5000; // TODO: Make it customizable.

    private enum StatsType {

    @VisibleForTesting

    enum StatsType {

        STATS_PER_IFACE,

        STATS_PER_UID,

    }

        maybeSchedulePollingStats();

    };

    @VisibleForTesting

    static class Dependencies {

        int getPerformPollInterval() {

            // TODO: Consider make this configurable.

     * A BPF tethering stats provider to provide network statistics to the system.

     * Note that this class's data may only be accessed on the handler thread.

     */

    private class BpfTetherStatsProvider extends NetworkStatsProvider {

    @VisibleForTesting

    class BpfTetherStatsProvider extends NetworkStatsProvider {

        // The offloaded traffic statistics per interface that has not been reported since the

        // last call to pushTetherStats. Only the interfaces that were ever tethering upstreams

        // and has pending tether stats delta are included in this NetworkStats object.

            // no-op

        }

        private void pushTetherStats() {

        @VisibleForTesting

        void pushTetherStats() {

            try {

                // The token is not used for now. See b/153606961.

                notifyStatsUpdated(0 /* token */, mIfaceStats, mUidStats);

/*

 * Copyright (C) 2020 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.networkstack.tethering;

import static android.net.NetworkStats.DEFAULT_NETWORK_NO;

import static android.net.NetworkStats.METERED_NO;

import static android.net.NetworkStats.ROAMING_NO;

import static android.net.NetworkStats.SET_DEFAULT;

import static android.net.NetworkStats.TAG_NONE;

import static android.net.NetworkStats.UID_ALL;

import static android.net.NetworkStats.UID_TETHERING;

import static com.android.networkstack.tethering.BpfCoordinator

        .DEFAULT_PERFORM_POLL_INTERVAL_MS;

import static com.android.networkstack.tethering.BpfCoordinator.StatsType;

import static com.android.networkstack.tethering.BpfCoordinator.StatsType.STATS_PER_IFACE;

import static com.android.networkstack.tethering.BpfCoordinator.StatsType.STATS_PER_UID;

import static junit.framework.Assert.assertNotNull;

import static org.mockito.Matchers.anyString;

import static org.mockito.Mockito.clearInvocations;

import static org.mockito.Mockito.never;

import static org.mockito.Mockito.verify;

import static org.mockito.Mockito.when;

import android.annotation.NonNull;

import android.app.usage.NetworkStatsManager;

import android.net.INetd;

import android.net.NetworkStats;

import android.net.TetherStatsParcel;

import android.net.util.SharedLog;

import android.os.Handler;

import android.os.test.TestLooper;

import androidx.test.filters.SmallTest;

import androidx.test.runner.AndroidJUnit4;

import com.android.testutils.TestableNetworkStatsProviderCbBinder;

import org.junit.Before;

import org.junit.Test;

import org.junit.runner.RunWith;

import org.mockito.ArgumentCaptor;

import org.mockito.Mock;

import org.mockito.MockitoAnnotations;

import java.util.ArrayList;

@RunWith(AndroidJUnit4.class)

@SmallTest

public class BpfCoordinatorTest {

    @Mock private NetworkStatsManager mStatsManager;

    @Mock private INetd mNetd;

    // Late init since methods must be called by the thread that created this object.

    private TestableNetworkStatsProviderCbBinder mTetherStatsProviderCb;

    private BpfCoordinator.BpfTetherStatsProvider mTetherStatsProvider;

    private final ArgumentCaptor<ArrayList> mStringArrayCaptor =

            ArgumentCaptor.forClass(ArrayList.class);

    private final TestLooper mTestLooper = new TestLooper();

    private BpfCoordinator.Dependencies mDeps =

            new BpfCoordinator.Dependencies() {

            @Override

            int getPerformPollInterval() {

                return DEFAULT_PERFORM_POLL_INTERVAL_MS;

            }

    };

    @Before public void setUp() {

        MockitoAnnotations.initMocks(this);

    }

    private void waitForIdle() {

        mTestLooper.dispatchAll();

    }

    private void setupFunctioningNetdInterface() throws Exception {

        when(mNetd.tetherOffloadGetStats()).thenReturn(new TetherStatsParcel[0]);

    }

    @NonNull

    private BpfCoordinator makeBpfCoordinator() throws Exception {

        BpfCoordinator coordinator = new BpfCoordinator(

                new Handler(mTestLooper.getLooper()), mNetd, mStatsManager, new SharedLog("test"),

                mDeps);

        final ArgumentCaptor<BpfCoordinator.BpfTetherStatsProvider>

                tetherStatsProviderCaptor =

                ArgumentCaptor.forClass(BpfCoordinator.BpfTetherStatsProvider.class);

        verify(mStatsManager).registerNetworkStatsProvider(anyString(),

                tetherStatsProviderCaptor.capture());

        mTetherStatsProvider = tetherStatsProviderCaptor.getValue();

        assertNotNull(mTetherStatsProvider);

        mTetherStatsProviderCb = new TestableNetworkStatsProviderCbBinder();

        mTetherStatsProvider.setProviderCallbackBinder(mTetherStatsProviderCb);

        return coordinator;

    }

    @NonNull

    private static NetworkStats.Entry buildTestEntry(@NonNull StatsType how,

            @NonNull String iface, long rxBytes, long rxPackets, long txBytes, long txPackets) {

        return new NetworkStats.Entry(iface, how == STATS_PER_IFACE ? UID_ALL : UID_TETHERING,

                SET_DEFAULT, TAG_NONE, METERED_NO, ROAMING_NO, DEFAULT_NETWORK_NO, rxBytes,

                rxPackets, txBytes, txPackets, 0L);

    }

    @NonNull

    private static TetherStatsParcel buildTestTetherStatsParcel(@NonNull Integer ifIndex,

            long rxBytes, long rxPackets, long txBytes, long txPackets) {

        final TetherStatsParcel parcel = new TetherStatsParcel();

        parcel.ifIndex = ifIndex;

        parcel.rxBytes = rxBytes;

        parcel.rxPackets = rxPackets;

        parcel.txBytes = txBytes;

        parcel.txPackets = txPackets;

        return parcel;

    }

    private void setTetherOffloadStatsList(TetherStatsParcel[] tetherStatsList) throws Exception {

        when(mNetd.tetherOffloadGetStats()).thenReturn(tetherStatsList);

        mTestLooper.moveTimeForward(DEFAULT_PERFORM_POLL_INTERVAL_MS);

        waitForIdle();

    }

    @Test

    public void testGetForwardedStats() throws Exception {

        setupFunctioningNetdInterface();

        final BpfCoordinator coordinator = makeBpfCoordinator();

        coordinator.start();

        final String wlanIface = "wlan0";

        final Integer wlanIfIndex = 100;

        final String mobileIface = "rmnet_data0";

        final Integer mobileIfIndex = 101;

        // Add interface name to lookup table. In realistic case, the upstream interface name will

        // be added by IpServer when IpServer has received with a new IPv6 upstream update event.

        coordinator.addUpstreamNameToLookupTable(wlanIfIndex, wlanIface);

        coordinator.addUpstreamNameToLookupTable(mobileIfIndex, mobileIface);

        // [1] Both interface stats are changed.

        // Setup the tether stats of wlan and mobile interface. Note that move forward the time of

        // the looper to make sure the new tether stats has been updated by polling update thread.

        setTetherOffloadStatsList(new TetherStatsParcel[] {

                buildTestTetherStatsParcel(wlanIfIndex, 1000, 100, 2000, 200),

                buildTestTetherStatsParcel(mobileIfIndex, 3000, 300, 4000, 400)});

        final NetworkStats expectedIfaceStats = new NetworkStats(0L, 2)

                .addEntry(buildTestEntry(STATS_PER_IFACE, wlanIface, 1000, 100, 2000, 200))

                .addEntry(buildTestEntry(STATS_PER_IFACE, mobileIface, 3000, 300, 4000, 400));

        final NetworkStats expectedUidStats = new NetworkStats(0L, 2)

                .addEntry(buildTestEntry(STATS_PER_UID, wlanIface, 1000, 100, 2000, 200))

                .addEntry(buildTestEntry(STATS_PER_UID, mobileIface, 3000, 300, 4000, 400));

        // Force pushing stats update to verify the stats reported.

        // TODO: Perhaps make #expectNotifyStatsUpdated to use test TetherStatsParcel object for

        // verifying the notification.

        mTetherStatsProvider.pushTetherStats();

        mTetherStatsProviderCb.expectNotifyStatsUpdated(expectedIfaceStats, expectedUidStats);

        // [2] Only one interface stats is changed.

        // The tether stats of mobile interface is accumulated and The tether stats of wlan

        // interface is the same.

        setTetherOffloadStatsList(new TetherStatsParcel[] {

                buildTestTetherStatsParcel(wlanIfIndex, 1000, 100, 2000, 200),

                buildTestTetherStatsParcel(mobileIfIndex, 3010, 320, 4030, 440)});

        final NetworkStats expectedIfaceStatsDiff = new NetworkStats(0L, 2)

                .addEntry(buildTestEntry(STATS_PER_IFACE, wlanIface, 0, 0, 0, 0))

                .addEntry(buildTestEntry(STATS_PER_IFACE, mobileIface, 10, 20, 30, 40));

        final NetworkStats expectedUidStatsDiff = new NetworkStats(0L, 2)

                .addEntry(buildTestEntry(STATS_PER_UID, wlanIface, 0, 0, 0, 0))

                .addEntry(buildTestEntry(STATS_PER_UID, mobileIface, 10, 20, 30, 40));

        // Force pushing stats update to verify that only diff of stats is reported.

        mTetherStatsProvider.pushTetherStats();

        mTetherStatsProviderCb.expectNotifyStatsUpdated(expectedIfaceStatsDiff,

                expectedUidStatsDiff);

        // [3] Stop coordinator.

        // Shutdown the coordinator and clear the invocation history, especially the

        // tetherOffloadGetStats() calls.

        coordinator.stop();

        clearInvocations(mNetd);

        // Verify the polling update thread stopped.

        mTestLooper.moveTimeForward(DEFAULT_PERFORM_POLL_INTERVAL_MS);

        waitForIdle();

        verify(mNetd, never()).tetherOffloadGetStats();

    }

}