Add network change monitoring

instrumentation/src/main/java/io/opentelemetry/android/OpenTelemetryRumBuilder.java

@@ -13,6 +13,7 @@
 import io.opentelemetry.android.instrumentation.activity.VisibleScreenTracker;
 import io.opentelemetry.android.instrumentation.network.CurrentNetworkProvider;
 import io.opentelemetry.android.instrumentation.network.NetworkAttributesSpanAppender;
+import io.opentelemetry.android.instrumentation.network.NetworkChangeMonitor;
 import io.opentelemetry.android.instrumentation.startup.InitializationEvents;
 import io.opentelemetry.android.instrumentation.startup.SdkInitializationEvents;
 import io.opentelemetry.api.baggage.propagation.W3CBaggagePropagator;
@@ -36,6 +37,7 @@
 import java.util.function.BiFunction;
 import java.util.function.Consumer;
 import java.util.function.Function;
+import javax.annotation.Nullable;
 
 /**
  * A builder of {@link OpenTelemetryRum}. It enabled configuring the OpenTelemetry SDK and disabling
@@ -65,6 +67,7 @@ public final class OpenTelemetryRumBuilder {
             (a) -> a;
 
     private Resource resource;
+    @Nullable private CurrentNetworkProvider currentNetworkProvider = null;
     private InitializationEvents initializationEvents = InitializationEvents.NO_OP;
 
     private static TextMapPropagator buildDefaultPropagator() {
@@ -91,6 +94,18 @@ public OpenTelemetryRumBuilder setResource(Resource resource) {
         return this;
     }
 
+    /**
+     * Call this to pass an existing CurrentNetworkProvider instance to share with the underlying
+     * OpenTelemetry Rum instrumentation.
+     *
+     * @return {@code this}
+     */
+    public OpenTelemetryRumBuilder setCurrentNetworkProvider(
+            CurrentNetworkProvider currentNetworkProvider) {
+        this.currentNetworkProvider = currentNetworkProvider;
+        return this;
+    }
+
     /**
      * Merges a new {@link Resource} with any existing {@link Resource} in this builder. The
      * resulting {@link Resource} will be attached to all telemetry emitted by the {@link
@@ -265,8 +280,7 @@ private void applyConfiguration() {
         // Network specific attributes
         if (config.shouldIncludeNetworkAttributes()) {
             // Add span processor that appends network attributes.
-            CurrentNetworkProvider currentNetworkProvider =
-                    CurrentNetworkProvider.createAndStart(application);
+            CurrentNetworkProvider currentNetworkProvider = getOrCreateCurrentNetworkProvider();
             addTracerProviderCustomizer(
                     (tracerProviderBuilder, app) -> {
                         SpanProcessor networkAttributesSpanAppender =
@@ -277,6 +291,16 @@ private void applyConfiguration() {
             initializationEvents.currentNetworkProviderInitialized();
         }
 
+        // Add network change monitor if enabled (default = = true)
+        if (config.isNetworkChangeMonitoringEnabled()) {
+            addInstrumentation(
+                    app -> {
+                        NetworkChangeMonitor.create(getOrCreateCurrentNetworkProvider())
+                                .installOn(app);
+                        initializationEvents.networkMonitorInitialized();
+                    });
+        }
+
         // Add span processor that appends screen attribute(s)
         if (config.shouldIncludeScreenAttributes()) {
             addTracerProviderCustomizer(
@@ -288,6 +312,13 @@ private void applyConfiguration() {
         }
     }
 
+    private CurrentNetworkProvider getOrCreateCurrentNetworkProvider() {
+        if (currentNetworkProvider == null) {
+            this.currentNetworkProvider = CurrentNetworkProvider.createAndStart(application);
+        }
+        return currentNetworkProvider;
+    }
+
     private SdkTracerProvider buildTracerProvider(SessionId sessionId, Application application) {
         SdkTracerProviderBuilder tracerProviderBuilder =
                 SdkTracerProvider.builder()

instrumentation/src/main/java/io/opentelemetry/android/config/OtelRumConfig.java

@@ -23,6 +23,7 @@ public class OtelRumConfig {
     private boolean includeScreenAttributes = true;
     private DiskBufferingConfiguration diskBufferingConfiguration =
             DiskBufferingConfiguration.builder().build();
+    private boolean networkChangeMonitoringEnabled = true;
 
     /**
      * Configures the set of global attributes to emit with every span and event. Any existing
@@ -103,4 +104,12 @@ public void setDiskBufferingConfiguration(
             DiskBufferingConfiguration diskBufferingConfiguration) {
         this.diskBufferingConfiguration = diskBufferingConfiguration;
     }
+
+    public void disableNetworkChangeMonitoring() {
+        this.networkChangeMonitoringEnabled = false;
+    }
+
+    public boolean isNetworkChangeMonitoringEnabled() {
+        return this.networkChangeMonitoringEnabled;
+    }
 }

instrumentation/src/main/java/io/opentelemetry/android/instrumentation/startup/InitializationEvents.java

@@ -15,6 +15,8 @@ public interface InitializationEvents {
 
     void currentNetworkProviderInitialized();
 
+    void networkMonitorInitialized();
+
     InitializationEvents NO_OP =
             new InitializationEvents() {
                 @Override
@@ -25,5 +27,8 @@ public void recordConfiguration(OtelRumConfig config) {}
 
                 @Override
                 public void currentNetworkProviderInitialized() {}
+
+                @Override
+                public void networkMonitorInitialized() {}
             };
 }

instrumentation/src/main/java/io/opentelemetry/android/instrumentation/startup/SdkInitializationEvents.java

@@ -23,4 +23,9 @@ public void recordConfiguration(OtelRumConfig config) {
     public void currentNetworkProviderInitialized() {
         // TODO: Build me
     }
+
+    @Override
+    public void networkMonitorInitialized() {
+        // TOOD: Build me "networkMonitorInitialized"
+    }
 }

instrumentation/src/test/java/io/opentelemetry/android/OpenTelemetryRumBuilderTest.java

@@ -34,6 +34,7 @@
 import java.time.Duration;
 import java.util.List;
 import java.util.function.Function;
+import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.ArgumentCaptor;
@@ -49,11 +50,17 @@ class OpenTelemetryRumBuilderTest {
     final InMemorySpanExporter spanExporter = InMemorySpanExporter.create();
 
     @Mock Application application;
+    @Mock android.content.Context applicationContext;
     @Mock Activity activity;
     @Mock ApplicationStateListener listener;
 
     @Captor ArgumentCaptor<Application.ActivityLifecycleCallbacks> activityCallbacksCaptor;
 
+    @BeforeEach
+    void setup() {
+        when(application.getApplicationContext()).thenReturn(applicationContext);
+    }
+
     @Test
     void shouldRegisterApplicationStateWatcher() {
         makeBuilder().build();