Add an experiment to allow a phased transition from the old GCM API to the current FCM API

service/src/main/java/org/whispersystems/textsecuregcm/WhisperServerService.java

@@ -144,6 +144,7 @@ import org.whispersystems.textsecuregcm.providers.RedisClusterHealthCheck;
 import org.whispersystems.textsecuregcm.push.APNSender;
 import org.whispersystems.textsecuregcm.push.ApnFallbackManager;
 import org.whispersystems.textsecuregcm.push.ClientPresenceManager;
+import org.whispersystems.textsecuregcm.push.FcmSender;
 import org.whispersystems.textsecuregcm.push.GCMSender;
 import org.whispersystems.textsecuregcm.push.MessageSender;
 import org.whispersystems.textsecuregcm.push.ProvisioningManager;
@@ -447,7 +448,8 @@ public class WhisperServerService extends Application<WhisperServerConfiguration
     DispatchManager            dispatchManager            = new DispatchManager(pubSubClientFactory, Optional.empty());
     PubSubManager              pubSubManager              = new PubSubManager(pubsubClient, dispatchManager);
     APNSender                  apnSender                  = new APNSender(apnSenderExecutor, accountsManager, config.getApnConfiguration());
-    GCMSender                  gcmSender                  = new GCMSender(gcmSenderExecutor, accountsManager, config.getGcmConfiguration().getApiKey());
+    FcmSender                  fcmSender                  = new FcmSender(gcmSenderExecutor, accountsManager, config.getFcmConfiguration().credentials());
+    GCMSender                  gcmSender                  = new GCMSender(gcmSenderExecutor, accountsManager, config.getGcmConfiguration().getApiKey(), experimentEnrollmentManager, fcmSender);
     RateLimiters               rateLimiters               = new RateLimiters(config.getLimitsConfiguration(), rateLimitersCluster);
     DynamicRateLimiters        dynamicRateLimiters        = new DynamicRateLimiters(rateLimitersCluster, dynamicConfigurationManager);
     ProvisioningManager        provisioningManager        = new ProvisioningManager(pubSubManager);

service/src/main/java/org/whispersystems/textsecuregcm/push/GCMSender.java

@@ -23,6 +23,7 @@ import org.slf4j.LoggerFactory;
 import org.whispersystems.gcm.server.Message;
 import org.whispersystems.gcm.server.Result;
 import org.whispersystems.gcm.server.Sender;
+import org.whispersystems.textsecuregcm.experiment.ExperimentEnrollmentManager;
 import org.whispersystems.textsecuregcm.storage.Account;
 import org.whispersystems.textsecuregcm.storage.AccountsManager;
 import org.whispersystems.textsecuregcm.storage.Device;
@@ -54,20 +55,32 @@ public class GCMSender {
   private final Sender            signalSender;
   private final ExecutorService   executor;
 
-  public GCMSender(ExecutorService executor, AccountsManager accountsManager, String signalKey) {
+  private final ExperimentEnrollmentManager experimentEnrollmentManager;
-    this(executor, accountsManager, new Sender(signalKey, SystemMapper.getMapper(), 6));
+  private final FcmSender fcmSender;
+
+  public GCMSender(ExecutorService executor, AccountsManager accountsManager, String signalKey, ExperimentEnrollmentManager experimentEnrollmentManager, FcmSender fcmSender) {
+    this(executor, accountsManager, new Sender(signalKey, SystemMapper.getMapper(), 6), experimentEnrollmentManager, fcmSender);
 
     CircuitBreakerUtil.registerMetrics(metricRegistry, signalSender.getRetry(), Sender.class);
   }
 
   @VisibleForTesting
-  public GCMSender(ExecutorService executor, AccountsManager accountsManager, Sender sender) {
+  public GCMSender(ExecutorService executor, AccountsManager accountsManager, Sender sender, ExperimentEnrollmentManager experimentEnrollmentManager, FcmSender fcmSender) {
     this.accountsManager = accountsManager;
     this.signalSender    = sender;
     this.executor        = executor;
+    this.experimentEnrollmentManager = experimentEnrollmentManager;
+    this.fcmSender = fcmSender;
   }
 
   public void sendMessage(GcmMessage message) {
+    final boolean useFcmSender = message.getUuid()
+        .map(uuid -> experimentEnrollmentManager.isEnrolled(uuid, "fcmSender"))
+        .orElse(false);
+
+    if (useFcmSender) {
+      fcmSender.sendMessage(message);
+    } else {
       Message.Builder builder = Message.newBuilder()
           .withDestination(message.getGcmId())
           .withPriority("high");
@@ -75,10 +88,17 @@ public class GCMSender {
       String key;
 
       switch (message.getType()) {
-      case NOTIFICATION:         key = "notification";         break;
+        case NOTIFICATION:
-      case CHALLENGE:            key = "challenge";            break;
+          key = "notification";
-      case RATE_LIMIT_CHALLENGE: key = "rateLimitChallenge"; break;
+          break;
-      default:                   throw new AssertionError();
+        case CHALLENGE:
+          key = "challenge";
+          break;
+        case RATE_LIMIT_CHALLENGE:
+          key = "rateLimitChallenge";
+          break;
+        default:
+          throw new AssertionError();
       }
 
       Message request = builder.withDataPart(key, message.getData().orElse("")).build();
@@ -104,6 +124,7 @@ public class GCMSender {
         return null;
       });
     }
+  }
 
   private void handleBadRegistration(GcmMessage message) {
     Optional<Account> account = getAccountForEvent(message);

service/src/test/java/org/whispersystems/textsecuregcm/tests/push/GCMSenderTest.java

@@ -19,6 +19,8 @@ import org.junit.jupiter.api.Test;
 import org.whispersystems.gcm.server.Message;
 import org.whispersystems.gcm.server.Result;
 import org.whispersystems.gcm.server.Sender;
+import org.whispersystems.textsecuregcm.experiment.ExperimentEnrollmentManager;
+import org.whispersystems.textsecuregcm.push.FcmSender;
 import org.whispersystems.textsecuregcm.push.GCMSender;
 import org.whispersystems.textsecuregcm.push.GcmMessage;
 import org.whispersystems.textsecuregcm.storage.Account;
@@ -45,7 +47,7 @@ class GCMSenderTest {
     AccountsHelper.setupMockUpdate(accountsManager);
 
     GcmMessage message = new GcmMessage("foo", UUID.randomUUID(), 1, GcmMessage.Type.NOTIFICATION, Optional.empty());
-    GCMSender gcmSender = new GCMSender(executorService, accountsManager, sender);
+    GCMSender gcmSender = new GCMSender(executorService, accountsManager, sender, mock(ExperimentEnrollmentManager.class), mock(FcmSender.class));
 
     CompletableFuture<Result> successFuture = CompletableFuture.completedFuture(successResult);
 
@@ -81,7 +83,7 @@ class GCMSenderTest {
     when(invalidResult.isSuccess()).thenReturn(true);
 
     GcmMessage message = new GcmMessage(gcmId, destinationUuid, 1, GcmMessage.Type.NOTIFICATION, Optional.empty());
-    GCMSender gcmSender = new GCMSender(executorService, accountsManager, sender);
+    GCMSender gcmSender = new GCMSender(executorService, accountsManager, sender, mock(ExperimentEnrollmentManager.class), mock(FcmSender.class));
 
     CompletableFuture<Result> invalidFuture = CompletableFuture.completedFuture(invalidResult);
 
@@ -122,7 +124,7 @@ class GCMSenderTest {
     when(canonicalResult.getCanonicalRegistrationId()).thenReturn(canonicalId);
 
     GcmMessage message = new GcmMessage(gcmId, destinationUuid, 1, GcmMessage.Type.NOTIFICATION, Optional.empty());
-    GCMSender gcmSender = new GCMSender(executorService, accountsManager, sender);
+    GCMSender gcmSender = new GCMSender(executorService, accountsManager, sender, mock(ExperimentEnrollmentManager.class), mock(FcmSender.class));
 
     CompletableFuture<Result> invalidFuture = CompletableFuture.completedFuture(canonicalResult);