Open source the Android NetInfo module

Reviewed By: mkonicek

Differential Revision: D2703432

fb-gh-sync-id: 4a85844f1734ec433df543c89f0fdd56fe5db13c

ReactAndroid/src/main/java/com/facebook/react/modules/netinfo/ConnectivityModule.java

@@ -0,0 +1,154 @@
+// Copyright 2004-present Facebook. All Rights Reserved.
+
+package com.facebook.react.modules.netinfo;
+
+import javax.annotation.Nullable;
+
+import android.content.BroadcastReceiver;
+import android.content.Context;
+import android.content.Intent;
+import android.content.IntentFilter;
+import android.net.ConnectivityManager;
+import android.net.NetworkInfo;
+import android.support.v4.net.ConnectivityManagerCompat;
+
+import com.facebook.react.bridge.Callback;
+import com.facebook.react.bridge.ReactApplicationContext;
+import com.facebook.react.bridge.ReactContext;
+import com.facebook.react.bridge.ReactContextBaseJavaModule;
+import com.facebook.react.bridge.ReactMethod;
+import com.facebook.react.bridge.LifecycleEventListener;
+import com.facebook.react.bridge.WritableMap;
+import com.facebook.react.bridge.WritableNativeMap;
+
+import static com.facebook.react.modules.core.DeviceEventManagerModule.RCTDeviceEventEmitter;
+
+/**
+ * Module that monitors and provides information about the connectivity state of the device.
+ */
+public class ConnectivityModule extends ReactContextBaseJavaModule
+    implements LifecycleEventListener {
+
+  private static final String CONNECTION_TYPE_NONE = "NONE";
+  private static final String CONNECTION_TYPE_UNKNOWN = "UNKNOWN";
+
+  private final ConnectivityManager mConnectivityManager;
+  private final ConnectivityManagerCompat mConnectivityManagerCompat;
+
+  private String mConnectivity;
+  private @Nullable ConnectivityBroadcastReceiver mConnectivityBroadcastReceiver;
+
+  public ConnectivityModule(ReactApplicationContext reactContext) {
+    super(reactContext);
+    mConnectivityManager =
+        (ConnectivityManager) reactContext.getSystemService(Context.CONNECTIVITY_SERVICE);
+    mConnectivityManagerCompat = new ConnectivityManagerCompat();
+    mConnectivity = "";
+  }
+
+  @Override
+  public void onHostResume() {
+    maybeRegisterReceiver();
+    updateAndSendConnectionType();
+  }
+
+  @Override
+  public void onHostPause() {
+    maybeUnregisterReceiver();
+  }
+
+  @Override
+  public void onHostDestroy() {
+  }
+
+  @Override
+  public void initialize() {
+    getReactApplicationContext().addLifecycleEventListener(this);
+    maybeRegisterReceiver();
+    updateAndSendConnectionType();
+  }
+
+  @Override
+  public void onCatalystInstanceDestroy() {
+    maybeUnregisterReceiver();
+  }
+
+  @Override
+  public String getName() {
+    return "NetInfo";
+  }
+
+  @ReactMethod
+  public void getCurrentConnectivity(Callback successCallback, Callback errorCallback) {
+    successCallback.invoke(createConnectivityEventMap());
+  }
+
+  @ReactMethod
+  public void isConnectionMetered(Callback successCallback) {
+    successCallback.invoke(mConnectivityManagerCompat.isActiveNetworkMetered(mConnectivityManager));
+  }
+
+  private void maybeRegisterReceiver() {
+    if (mConnectivityBroadcastReceiver != null) {
+      return;
+    }
+    mConnectivityBroadcastReceiver = new ConnectivityBroadcastReceiver();
+    IntentFilter filter = new IntentFilter();
+    filter.addAction(ConnectivityManager.CONNECTIVITY_ACTION);
+    getReactApplicationContext().registerReceiver(mConnectivityBroadcastReceiver, filter);
+  }
+
+  private void maybeUnregisterReceiver() {
+    if (mConnectivityBroadcastReceiver == null) {
+      return;
+    }
+    getReactApplicationContext().unregisterReceiver(mConnectivityBroadcastReceiver);
+    mConnectivityBroadcastReceiver = null;
+    mConnectivity = "";
+  }
+
+  private void updateAndSendConnectionType() {
+    String currentConnectivity = getCurrentConnectionType();
+    // It is possible to get multiple broadcasts for the same connectivity change, so we only
+    // update and send an event when the connectivity has indeed changed.
+    if (!currentConnectivity.equalsIgnoreCase(mConnectivity)) {
+      mConnectivity = currentConnectivity;
+      sendConnectivityChangedEvent();
+    }
+  }
+
+  private String getCurrentConnectionType() {
+    NetworkInfo networkInfo = mConnectivityManager.getActiveNetworkInfo();
+    if (networkInfo == null || !networkInfo.isConnected()) {
+      return CONNECTION_TYPE_NONE;
+    } else if (ConnectivityManager.isNetworkTypeValid(networkInfo.getType())) {
+      return networkInfo.getTypeName().toUpperCase();
+    } else {
+      return CONNECTION_TYPE_UNKNOWN;
+    }
+  }
+  private void sendConnectivityChangedEvent() {
+    getReactApplicationContext().getJSModule(RCTDeviceEventEmitter.class)
+        .emit("networkStatusDidChange", createConnectivityEventMap());
+  }
+
+  private WritableMap createConnectivityEventMap() {
+    WritableMap event = new WritableNativeMap();
+    event.putString("network_info", mConnectivity);
+    return event;
+  }
+
+  /**
+   * Class that receives intents whenever the connection type changes.
+   * NB: It is possible on some devices to receive certain connection type changes multiple times.
+   */
+  private class ConnectivityBroadcastReceiver extends BroadcastReceiver {
+
+    @Override
+    public void onReceive(Context context, Intent intent) {
+      if (intent.getAction().equals(ConnectivityManager.CONNECTIVITY_ACTION)) {
+        updateAndSendConnectionType();
+      }
+    }
+  }
+}

ReactAndroid/src/main/java/com/facebook/react/shell/MainReactPackage.java

@@ -20,6 +20,7 @@ import com.facebook.react.bridge.ReactApplicationContext;
 import com.facebook.react.modules.fresco.FrescoModule;
 import com.facebook.react.modules.intent.IntentModule;
 import com.facebook.react.modules.location.LocationModule;
+import com.facebook.react.modules.netinfo.ConnectivityModule;
 import com.facebook.react.modules.network.NetworkingModule;
 import com.facebook.react.modules.storage.AsyncStorageModule;
 import com.facebook.react.modules.toast.ToastModule;
@@ -54,6 +55,7 @@ public class MainReactPackage implements ReactPackage {
       new IntentModule(reactContext),
       new LocationModule(reactContext),
       new NetworkingModule(reactContext),
+      new ConnectivityModule(reactContext),
       new WebSocketModule(reactContext),
       new ToastModule(reactContext));
   }