Merge "Support discovering services with a NetworkRequest" am: 7b8b3ccb8e
Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/1952113
Change-Id: I6ffad96f4e0e662be9b21607d12648f0b4d0aa81
diff --git a/framework-t/src/android/net/nsd/NsdManager.java b/framework-t/src/android/net/nsd/NsdManager.java
index ea69e09..512fbce 100644
--- a/framework-t/src/android/net/nsd/NsdManager.java
+++ b/framework-t/src/android/net/nsd/NsdManager.java
@@ -18,6 +18,7 @@
import android.annotation.NonNull;
import android.annotation.Nullable;
+import android.annotation.RequiresPermission;
import android.annotation.SdkConstant;
import android.annotation.SdkConstant.SdkConstantType;
import android.annotation.SystemService;
@@ -25,16 +26,22 @@
import android.compat.annotation.ChangeId;
import android.compat.annotation.EnabledSince;
import android.content.Context;
+import android.net.ConnectivityManager;
+import android.net.ConnectivityManager.NetworkCallback;
import android.net.Network;
+import android.net.NetworkRequest;
import android.os.Handler;
import android.os.HandlerThread;
import android.os.Looper;
import android.os.Message;
import android.os.RemoteException;
import android.text.TextUtils;
+import android.util.ArrayMap;
+import android.util.ArraySet;
import android.util.Log;
import android.util.SparseArray;
+import com.android.internal.annotations.GuardedBy;
import com.android.internal.annotations.VisibleForTesting;
import java.util.Objects;
@@ -281,9 +288,180 @@
private final SparseArray mListenerMap = new SparseArray();
private final SparseArray<NsdServiceInfo> mServiceMap = new SparseArray<>();
private final Object mMapLock = new Object();
+ // Map of listener key sent by client -> per-network discovery tracker
+ @GuardedBy("mPerNetworkDiscoveryMap")
+ private final ArrayMap<Integer, PerNetworkDiscoveryTracker>
+ mPerNetworkDiscoveryMap = new ArrayMap<>();
private final ServiceHandler mHandler;
+ private class PerNetworkDiscoveryTracker {
+ final String mServiceType;
+ final int mProtocolType;
+ final DiscoveryListener mBaseListener;
+ final ArrayMap<Network, DelegatingDiscoveryListener> mPerNetworkListeners =
+ new ArrayMap<>();
+
+ final NetworkCallback mNetworkCb = new NetworkCallback() {
+ @Override
+ public void onAvailable(@NonNull Network network) {
+ final DelegatingDiscoveryListener wrappedListener = new DelegatingDiscoveryListener(
+ network, mBaseListener);
+ mPerNetworkListeners.put(network, wrappedListener);
+ discoverServices(mServiceType, mProtocolType, network, wrappedListener);
+ }
+
+ @Override
+ public void onLost(@NonNull Network network) {
+ final DelegatingDiscoveryListener listener = mPerNetworkListeners.get(network);
+ if (listener == null) return;
+ listener.notifyAllServicesLost();
+ // Listener will be removed from map in discovery stopped callback
+ stopServiceDiscovery(listener);
+ }
+ };
+
+ // Accessed from mHandler
+ private boolean mStopRequested;
+
+ public void start(@NonNull NetworkRequest request) {
+ final ConnectivityManager cm = mContext.getSystemService(ConnectivityManager.class);
+ cm.registerNetworkCallback(request, mNetworkCb, mHandler);
+ mHandler.post(() -> mBaseListener.onDiscoveryStarted(mServiceType));
+ }
+
+ /**
+ * Stop discovery on all networks tracked by this class.
+ *
+ * This will request all underlying listeners to stop, and the last one to stop will call
+ * onDiscoveryStopped or onStopDiscoveryFailed.
+ *
+ * Must be called on the handler thread.
+ */
+ public void requestStop() {
+ mHandler.post(() -> {
+ mStopRequested = true;
+ final ConnectivityManager cm = mContext.getSystemService(ConnectivityManager.class);
+ cm.unregisterNetworkCallback(mNetworkCb);
+ if (mPerNetworkListeners.size() == 0) {
+ mBaseListener.onDiscoveryStopped(mServiceType);
+ return;
+ }
+ for (int i = 0; i < mPerNetworkListeners.size(); i++) {
+ final DelegatingDiscoveryListener listener = mPerNetworkListeners.valueAt(i);
+ stopServiceDiscovery(listener);
+ }
+ });
+ }
+
+ private PerNetworkDiscoveryTracker(String serviceType, int protocolType,
+ DiscoveryListener baseListener) {
+ mServiceType = serviceType;
+ mProtocolType = protocolType;
+ mBaseListener = baseListener;
+ }
+
+ /**
+ * Subset of NsdServiceInfo that is tracked to generate service lost notifications when a
+ * network is lost.
+ *
+ * Service lost notifications only contain service name, type and network, so only track
+ * that information (Network is known from the listener). This also implements
+ * equals/hashCode for usage in maps.
+ */
+ private class TrackedNsdInfo {
+ private final String mServiceName;
+ private final String mServiceType;
+ TrackedNsdInfo(NsdServiceInfo info) {
+ mServiceName = info.getServiceName();
+ mServiceType = info.getServiceType();
+ }
+
+ @Override
+ public int hashCode() {
+ return Objects.hash(mServiceName, mServiceType);
+ }
+
+ @Override
+ public boolean equals(Object obj) {
+ if (!(obj instanceof TrackedNsdInfo)) return false;
+ final TrackedNsdInfo other = (TrackedNsdInfo) obj;
+ return Objects.equals(mServiceName, other.mServiceName)
+ && Objects.equals(mServiceType, other.mServiceType);
+ }
+ }
+
+ private class DelegatingDiscoveryListener implements DiscoveryListener {
+ private final Network mNetwork;
+ private final DiscoveryListener mWrapped;
+ private final ArraySet<TrackedNsdInfo> mFoundInfo = new ArraySet<>();
+
+ private DelegatingDiscoveryListener(Network network, DiscoveryListener listener) {
+ mNetwork = network;
+ mWrapped = listener;
+ }
+
+ void notifyAllServicesLost() {
+ for (int i = 0; i < mFoundInfo.size(); i++) {
+ final TrackedNsdInfo trackedInfo = mFoundInfo.valueAt(i);
+ final NsdServiceInfo serviceInfo = new NsdServiceInfo(
+ trackedInfo.mServiceName, trackedInfo.mServiceType);
+ serviceInfo.setNetwork(mNetwork);
+ mWrapped.onServiceLost(serviceInfo);
+ }
+ }
+
+ @Override
+ public void onStartDiscoveryFailed(String serviceType, int errorCode) {
+ // The delegated listener is used when NsdManager takes care of starting/stopping
+ // discovery on multiple networks. Failure to start on one network is not a global
+ // failure to be reported up, as other networks may succeed: just log.
+ Log.e(TAG, "Failed to start discovery for " + serviceType + " on " + mNetwork
+ + " with code " + errorCode);
+ mPerNetworkListeners.remove(mNetwork);
+ }
+
+ @Override
+ public void onDiscoveryStarted(String serviceType) {
+ // Wrapped listener was called upon registration, it is not called for discovery
+ // on each network
+ }
+
+ @Override
+ public void onStopDiscoveryFailed(String serviceType, int errorCode) {
+ Log.e(TAG, "Failed to stop discovery for " + serviceType + " on " + mNetwork
+ + " with code " + errorCode);
+ mPerNetworkListeners.remove(mNetwork);
+ if (mStopRequested && mPerNetworkListeners.size() == 0) {
+ // Do not report onStopDiscoveryFailed when some underlying listeners failed:
+ // this does not mean that all listeners did, and onStopDiscoveryFailed is not
+ // actionable anyway. Just report that discovery stopped.
+ mWrapped.onDiscoveryStopped(serviceType);
+ }
+ }
+
+ @Override
+ public void onDiscoveryStopped(String serviceType) {
+ mPerNetworkListeners.remove(mNetwork);
+ if (mStopRequested && mPerNetworkListeners.size() == 0) {
+ mWrapped.onDiscoveryStopped(serviceType);
+ }
+ }
+
+ @Override
+ public void onServiceFound(NsdServiceInfo serviceInfo) {
+ mFoundInfo.add(new TrackedNsdInfo(serviceInfo));
+ mWrapped.onServiceFound(serviceInfo);
+ }
+
+ @Override
+ public void onServiceLost(NsdServiceInfo serviceInfo) {
+ mFoundInfo.remove(new TrackedNsdInfo(serviceInfo));
+ mWrapped.onServiceLost(serviceInfo);
+ }
+ }
+ }
+
/**
* Create a new Nsd instance. Applications use
* {@link android.content.Context#getSystemService Context.getSystemService()} to retrieve
@@ -641,7 +819,7 @@
* {@link Network}.
*/
public void discoverServices(String serviceType, int protocolType, DiscoveryListener listener) {
- discoverServices(serviceType, protocolType, null, listener);
+ discoverServices(serviceType, protocolType, (Network) null, listener);
}
/**
@@ -693,6 +871,67 @@
}
/**
+ * Initiate service discovery to browse for instances of a service type. Service discovery
+ * consumes network bandwidth and will continue until the application calls
+ * {@link #stopServiceDiscovery}.
+ *
+ * <p> The function call immediately returns after sending a request to start service
+ * discovery to the framework. The application is notified of a success to initiate
+ * discovery through the callback {@link DiscoveryListener#onDiscoveryStarted} or a failure
+ * through {@link DiscoveryListener#onStartDiscoveryFailed}.
+ *
+ * <p> Upon successful start, application is notified when a service is found with
+ * {@link DiscoveryListener#onServiceFound} or when a service is lost with
+ * {@link DiscoveryListener#onServiceLost}.
+ *
+ * <p> Upon failure to start, service discovery is not active and application does
+ * not need to invoke {@link #stopServiceDiscovery}
+ *
+ * <p> The application should call {@link #stopServiceDiscovery} when discovery of this
+ * service type is no longer required, and/or whenever the application is paused or
+ * stopped.
+ *
+ * <p> During discovery, new networks may connect or existing networks may disconnect - for
+ * example if wifi is reconnected. When a service was found on a network that disconnects,
+ * {@link DiscoveryListener#onServiceLost} will be called. If a new network connects that
+ * matches the {@link NetworkRequest}, {@link DiscoveryListener#onServiceFound} will be called
+ * for services found on that network. Applications that do not want to track networks
+ * themselves are encouraged to use this method instead of other overloads of
+ * {@code discoverServices}, as they will receive proper notifications when a service becomes
+ * available or unavailable due to network changes.
+ *
+ * @param serviceType The service type being discovered. Examples include "_http._tcp" for
+ * http services or "_ipp._tcp" for printers
+ * @param protocolType The service discovery protocol
+ * @param networkRequest Request specifying networks that should be considered when discovering
+ * @param listener The listener notifies of a successful discovery and is used
+ * to stop discovery on this serviceType through a call on {@link #stopServiceDiscovery}.
+ * Cannot be null. Cannot be in use for an active service discovery.
+ */
+ @RequiresPermission(android.Manifest.permission.ACCESS_NETWORK_STATE)
+ public void discoverServices(@NonNull String serviceType, int protocolType,
+ @NonNull NetworkRequest networkRequest, @NonNull DiscoveryListener listener) {
+ if (TextUtils.isEmpty(serviceType)) {
+ throw new IllegalArgumentException("Service type cannot be empty");
+ }
+ Objects.requireNonNull(networkRequest, "NetworkRequest cannot be null");
+ checkProtocol(protocolType);
+
+ NsdServiceInfo s = new NsdServiceInfo();
+ s.setServiceType(serviceType);
+
+ final int baseListenerKey = putListener(listener, s);
+
+ final PerNetworkDiscoveryTracker discoveryInfo = new PerNetworkDiscoveryTracker(
+ serviceType, protocolType, listener);
+
+ synchronized (mPerNetworkDiscoveryMap) {
+ mPerNetworkDiscoveryMap.put(baseListenerKey, discoveryInfo);
+ discoveryInfo.start(networkRequest);
+ }
+ }
+
+ /**
* Stop service discovery initiated with {@link #discoverServices}. An active service
* discovery is notified to the application with {@link DiscoveryListener#onDiscoveryStarted}
* and it stays active until the application invokes a stop service discovery. A successful
@@ -710,6 +949,14 @@
*/
public void stopServiceDiscovery(DiscoveryListener listener) {
int id = getListenerKey(listener);
+ // If this is a PerNetworkDiscovery request, handle it as such
+ synchronized (mPerNetworkDiscoveryMap) {
+ final PerNetworkDiscoveryTracker info = mPerNetworkDiscoveryMap.get(id);
+ if (info != null) {
+ info.requestStop();
+ return;
+ }
+ }
try {
mService.stopDiscovery(id);
} catch (RemoteException e) {