[Feature Sync] Remove expired service
The service will be removed after TTL. The client can enable this
feature by setting MdnsSearchOptions#Builder#\
setRemoveExpiredService(true).
Bug: 254155029
Test: atest FrameworksNetTests
Change-Id: I7feac748eb2f239316492e95626433b136e63392
diff --git a/service/mdns/com/android/server/connectivity/mdns/MdnsConfigs.java b/service/mdns/com/android/server/connectivity/mdns/MdnsConfigs.java
index 922037b..35a685d 100644
--- a/service/mdns/com/android/server/connectivity/mdns/MdnsConfigs.java
+++ b/service/mdns/com/android/server/connectivity/mdns/MdnsConfigs.java
@@ -89,4 +89,12 @@
public static boolean preferIpv6() {
return false;
}
+
+ public static boolean removeServiceAfterTtlExpires() {
+ return false;
+ }
+
+ public static boolean allowSearchOptionsToRemoveExpiredService() {
+ return false;
+ }
}
\ No newline at end of file
diff --git a/service/mdns/com/android/server/connectivity/mdns/MdnsSearchOptions.java b/service/mdns/com/android/server/connectivity/mdns/MdnsSearchOptions.java
index 6e90d2c..195bc8e 100644
--- a/service/mdns/com/android/server/connectivity/mdns/MdnsSearchOptions.java
+++ b/service/mdns/com/android/server/connectivity/mdns/MdnsSearchOptions.java
@@ -43,7 +43,7 @@
@Override
public MdnsSearchOptions createFromParcel(Parcel source) {
return new MdnsSearchOptions(source.createStringArrayList(),
- source.readBoolean());
+ source.readBoolean(), source.readBoolean());
}
@Override
@@ -55,14 +55,16 @@
private final List<String> subtypes;
private final boolean isPassiveMode;
+ private final boolean removeExpiredService;
/** Parcelable constructs for a {@link MdnsServiceInfo}. */
- MdnsSearchOptions(List<String> subtypes, boolean isPassiveMode) {
+ MdnsSearchOptions(List<String> subtypes, boolean isPassiveMode, boolean removeExpiredService) {
this.subtypes = new ArrayList<>();
if (subtypes != null) {
this.subtypes.addAll(subtypes);
}
this.isPassiveMode = isPassiveMode;
+ this.removeExpiredService = removeExpiredService;
}
/** Returns a {@link Builder} for {@link MdnsSearchOptions}. */
@@ -91,6 +93,11 @@
return isPassiveMode;
}
+ /** Returns {@code true} if service will be removed after its TTL expires. */
+ public boolean removeExpiredService() {
+ return removeExpiredService;
+ }
+
@Override
public int describeContents() {
return 0;
@@ -100,12 +107,14 @@
public void writeToParcel(Parcel out, int flags) {
out.writeStringList(subtypes);
out.writeBoolean(isPassiveMode);
+ out.writeBoolean(removeExpiredService);
}
/** A builder to create {@link MdnsSearchOptions}. */
public static final class Builder {
private final Set<String> subtypes;
private boolean isPassiveMode = true;
+ private boolean removeExpiredService;
private Builder() {
subtypes = new ArraySet<>();
@@ -136,8 +145,7 @@
/**
* Sets if the passive mode scan should be used. The passive mode scans less frequently in
- * order
- * to conserve battery and produce less network traffic.
+ * order to conserve battery and produce less network traffic.
*
* @param isPassiveMode If set to {@code true}, passive mode will be used. If set to {@code
* false}, active mode will be used.
@@ -147,9 +155,20 @@
return this;
}
+ /**
+ * Sets if the service should be removed after TTL.
+ *
+ * @param removeExpiredService If set to {@code true}, the service will be removed after TTL
+ */
+ public Builder setRemoveExpiredService(boolean removeExpiredService) {
+ this.removeExpiredService = removeExpiredService;
+ return this;
+ }
+
/** Builds a {@link MdnsSearchOptions} with the arguments supplied to this builder. */
public MdnsSearchOptions build() {
- return new MdnsSearchOptions(new ArrayList<>(subtypes), isPassiveMode);
+ return new MdnsSearchOptions(
+ new ArrayList<>(subtypes), isPassiveMode, removeExpiredService);
}
}
}
\ No newline at end of file
diff --git a/service/mdns/com/android/server/connectivity/mdns/MdnsServiceTypeClient.java b/service/mdns/com/android/server/connectivity/mdns/MdnsServiceTypeClient.java
index e335de9..4fbc809 100644
--- a/service/mdns/com/android/server/connectivity/mdns/MdnsServiceTypeClient.java
+++ b/service/mdns/com/android/server/connectivity/mdns/MdnsServiceTypeClient.java
@@ -16,7 +16,11 @@
package com.android.server.connectivity.mdns;
+import static java.util.concurrent.TimeUnit.MILLISECONDS;
+
import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.os.SystemClock;
import android.text.TextUtils;
import android.util.ArraySet;
import android.util.Pair;
@@ -28,12 +32,12 @@
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
+import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.Future;
import java.util.concurrent.ScheduledExecutorService;
-import java.util.concurrent.TimeUnit;
/**
* Instance of this class sends and receives mDNS packets of a given service type and invoke
@@ -53,6 +57,12 @@
private final Object lock = new Object();
private final Set<MdnsServiceBrowserListener> listeners = new ArraySet<>();
private final Map<String, MdnsResponse> instanceNameToResponse = new HashMap<>();
+ private final boolean removeServiceAfterTtlExpires =
+ MdnsConfigs.removeServiceAfterTtlExpires();
+ private final boolean allowSearchOptionsToRemoveExpiredService =
+ MdnsConfigs.allowSearchOptionsToRemoveExpiredService();
+
+ @Nullable private MdnsSearchOptions searchOptions;
// The session ID increases when startSendAndReceive() is called where we schedule a
// QueryTask for
@@ -115,6 +125,7 @@
@NonNull MdnsServiceBrowserListener listener,
@NonNull MdnsSearchOptions searchOptions) {
synchronized (lock) {
+ this.searchOptions = searchOptions;
if (!listeners.contains(listener)) {
listeners.add(listener);
for (MdnsResponse existingResponse : instanceNameToResponse.values()) {
@@ -164,10 +175,23 @@
}
public synchronized void processResponse(@NonNull MdnsResponse response) {
- if (response.isGoodbye()) {
- onGoodbyeReceived(response.getServiceInstanceName());
+ if (shouldRemoveServiceAfterTtlExpires()) {
+ // Because {@link QueryTask} and {@link processResponse} are running in different
+ // threads. We need to synchronize {@link lock} to protect
+ // {@link instanceNameToResponse} won’t be modified at the same time.
+ synchronized (lock) {
+ if (response.isGoodbye()) {
+ onGoodbyeReceived(response.getServiceInstanceName());
+ } else {
+ onResponseReceived(response);
+ }
+ }
} else {
- onResponseReceived(response);
+ if (response.isGoodbye()) {
+ onGoodbyeReceived(response.getServiceInstanceName());
+ } else {
+ onResponseReceived(response);
+ }
}
}
@@ -212,6 +236,15 @@
}
}
+ private boolean shouldRemoveServiceAfterTtlExpires() {
+ if (removeServiceAfterTtlExpires) {
+ return true;
+ }
+ return allowSearchOptionsToRemoveExpiredService
+ && searchOptions != null
+ && searchOptions.removeExpiredService();
+ }
+
@VisibleForTesting
MdnsPacketWriter createMdnsPacketWriter() {
return new MdnsPacketWriter(DEFAULT_MTU);
@@ -359,11 +392,27 @@
listener.onDiscoveryQuerySent(result.second, result.first);
}
}
+ if (shouldRemoveServiceAfterTtlExpires()) {
+ Iterator<MdnsResponse> iter = instanceNameToResponse.values().iterator();
+ while (iter.hasNext()) {
+ MdnsResponse existingResponse = iter.next();
+ if (existingResponse.isComplete()
+ && existingResponse
+ .getServiceRecord()
+ .getRemainingTTL(SystemClock.elapsedRealtime())
+ == 0) {
+ iter.remove();
+ for (MdnsServiceBrowserListener listener : listeners) {
+ listener.onServiceRemoved(
+ existingResponse.getServiceInstanceName());
+ }
+ }
+ }
+ }
QueryTaskConfig config = this.config.getConfigForNextRun();
requestTaskFuture =
executor.schedule(
- new QueryTask(config), config.timeToRunNextTaskInMs,
- TimeUnit.MILLISECONDS);
+ new QueryTask(config), config.timeToRunNextTaskInMs, MILLISECONDS);
}
}
}