Add callback registration in ConnectivityService.

ConnectivityDiagnosticsManager will send callbacks to
ConnectivityService for registering and unregistering them with the
system. ConnectivityService needs to do the processing for persisting
(and deleting) these callbacks on the ConnectivityService Thread, so
messages are sent to the Connectivity Diagnostics  Handler, which runs
on the ConnectivityService Thread.

Bug: 146444622
Bug: 143187964
Bug: 147848028
Test: compiles
Test: atest FrameworksNetTests
Change-Id: Ia5c8f90a60c050504e8676de9564a7607a9b03bc

tests/net/java/android/net/ConnectivityDiagnosticsManagerTest.java

@@ -27,12 +27,18 @@ import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertNotEquals;
 import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
+import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.verifyNoMoreInteractions;
 
+import android.content.Context;
 import android.os.PersistableBundle;
 
+import org.junit.After;
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
@@ -52,15 +58,27 @@ public class ConnectivityDiagnosticsManagerTest {
 
     private static final Executor INLINE_EXECUTOR = x -> x.run();
 
+    @Mock private Context mContext;
+    @Mock private IConnectivityManager mService;
     @Mock private ConnectivityDiagnosticsCallback mCb;
 
     private ConnectivityDiagnosticsBinder mBinder;
+    private ConnectivityDiagnosticsManager mManager;
 
     @Before
     public void setUp() {
+        mContext = mock(Context.class);
+        mService = mock(IConnectivityManager.class);
         mCb = mock(ConnectivityDiagnosticsCallback.class);
 
         mBinder = new ConnectivityDiagnosticsBinder(mCb, INLINE_EXECUTOR);
+        mManager = new ConnectivityDiagnosticsManager(mContext, mService);
+    }
+
+    @After
+    public void tearDown() {
+        // clear ConnectivityDiagnosticsManager callbacks map
+        ConnectivityDiagnosticsManager.sCallbacks.clear();
     }
 
     private ConnectivityReport createSampleConnectivityReport() {
@@ -245,4 +263,53 @@ public class ConnectivityDiagnosticsManagerTest {
         // latch without waiting.
         verify(mCb).onNetworkConnectivityReported(eq(n), eq(connectivity));
     }
+
+    @Test
+    public void testRegisterConnectivityDiagnosticsCallback() throws Exception {
+        final NetworkRequest request = new NetworkRequest.Builder().build();
+
+        mManager.registerConnectivityDiagnosticsCallback(request, INLINE_EXECUTOR, mCb);
+
+        verify(mService).registerConnectivityDiagnosticsCallback(
+                any(ConnectivityDiagnosticsBinder.class), eq(request));
+        assertTrue(ConnectivityDiagnosticsManager.sCallbacks.containsKey(mCb));
+    }
+
+    @Test
+    public void testRegisterDuplicateConnectivityDiagnosticsCallback() throws Exception {
+        final NetworkRequest request = new NetworkRequest.Builder().build();
+
+        mManager.registerConnectivityDiagnosticsCallback(request, INLINE_EXECUTOR, mCb);
+
+        try {
+            mManager.registerConnectivityDiagnosticsCallback(request, INLINE_EXECUTOR, mCb);
+            fail("Duplicate callback registration should fail");
+        } catch (IllegalArgumentException expected) {
+        }
+    }
+
+    @Test
+    public void testUnregisterConnectivityDiagnosticsCallback() throws Exception {
+        final NetworkRequest request = new NetworkRequest.Builder().build();
+        mManager.registerConnectivityDiagnosticsCallback(request, INLINE_EXECUTOR, mCb);
+
+        mManager.unregisterConnectivityDiagnosticsCallback(mCb);
+
+        verify(mService).unregisterConnectivityDiagnosticsCallback(
+                any(ConnectivityDiagnosticsBinder.class));
+        assertFalse(ConnectivityDiagnosticsManager.sCallbacks.containsKey(mCb));
+
+        // verify that re-registering is successful
+        mManager.registerConnectivityDiagnosticsCallback(request, INLINE_EXECUTOR, mCb);
+        verify(mService, times(2)).registerConnectivityDiagnosticsCallback(
+                any(ConnectivityDiagnosticsBinder.class), eq(request));
+        assertTrue(ConnectivityDiagnosticsManager.sCallbacks.containsKey(mCb));
+    }
+
+    @Test
+    public void testUnregisterUnknownConnectivityDiagnosticsCallback() throws Exception {
+        mManager.unregisterConnectivityDiagnosticsCallback(mCb);
+
+        verifyNoMoreInteractions(mService);
+    }
 }