Add metric for content-length header distribution

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

@@ -94,6 +94,7 @@ import org.whispersystems.textsecuregcm.currency.CurrencyConversionManager;
 import org.whispersystems.textsecuregcm.currency.FixerClient;
 import org.whispersystems.textsecuregcm.currency.FtxClient;
 import org.whispersystems.textsecuregcm.experiment.ExperimentEnrollmentManager;
+import org.whispersystems.textsecuregcm.filters.ContentLengthFilter;
 import org.whispersystems.textsecuregcm.filters.RemoteDeprecationFilter;
 import org.whispersystems.textsecuregcm.filters.TimestampResponseFilter;
 import org.whispersystems.textsecuregcm.limits.PreKeyRateLimiter;
@@ -545,6 +546,7 @@ public class WhisperServerService extends Application<WhisperServerConfiguration
     environment.servlets().addFilter("RemoteDeprecationFilter", new RemoteDeprecationFilter(dynamicConfigurationManager))
         .addMappingForUrlPatterns(EnumSet.of(DispatcherType.REQUEST), false, "/*");
 
+    environment.jersey().register(new ContentLengthFilter(TrafficSource.HTTP));
     environment.jersey().register(MultiRecipientMessageProvider.class);
     environment.jersey().register(new MetricsApplicationEventListener(TrafficSource.HTTP));
     environment.jersey().register(new PolymorphicAuthDynamicFeature<>(ImmutableMap.of(Account.class, accountAuthFilter,
@@ -556,7 +558,10 @@ public class WhisperServerService extends Application<WhisperServerConfiguration
     ///
     WebSocketEnvironment<Account> webSocketEnvironment = new WebSocketEnvironment<>(environment, config.getWebSocketConfiguration(), 90000);
     webSocketEnvironment.setAuthenticator(new WebSocketAccountAuthenticator(accountAuthenticator));
-    webSocketEnvironment.setConnectListener(new AuthenticatedConnectListener(receiptSender, messagesManager, messageSender, apnFallbackManager, clientPresenceManager, retrySchedulingExecutor));
+    webSocketEnvironment.setConnectListener(
+        new AuthenticatedConnectListener(receiptSender, messagesManager, messageSender, apnFallbackManager,
+            clientPresenceManager, retrySchedulingExecutor));
+    webSocketEnvironment.jersey().register(new ContentLengthFilter(TrafficSource.WEBSOCKET));
     webSocketEnvironment.jersey().register(MultiRecipientMessageProvider.class);
     webSocketEnvironment.jersey().register(new MetricsApplicationEventListener(TrafficSource.WEBSOCKET));
     webSocketEnvironment.jersey().register(new KeepAliveController(clientPresenceManager));

service/src/main/java/org/whispersystems/textsecuregcm/filters/ContentLengthFilter.java

@@ -0,0 +1,37 @@
+/*
+ * Copyright 2021 Signal Messenger, LLC
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+package org.whispersystems.textsecuregcm.filters;
+
+import static com.codahale.metrics.MetricRegistry.name;
+
+import io.micrometer.core.instrument.Metrics;
+import java.io.IOException;
+import javax.ws.rs.container.ContainerRequestContext;
+import javax.ws.rs.container.ContainerRequestFilter;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.whispersystems.textsecuregcm.metrics.TrafficSource;
+
+public class ContentLengthFilter implements ContainerRequestFilter {
+
+  private static final String CONTENT_LENGTH_DISTRIBUTION_NAME = name(ContentLengthFilter.class, "contentLength");
+
+  private static final Logger logger = LoggerFactory.getLogger(ContentLengthFilter.class);
+  private final TrafficSource trafficSource;
+
+  public ContentLengthFilter(final TrafficSource trafficeSource) {
+    this.trafficSource = trafficeSource;
+  }
+
+  @Override
+  public void filter(final ContainerRequestContext requestContext) throws IOException {
+    try {
+      Metrics.summary(CONTENT_LENGTH_DISTRIBUTION_NAME, "trafficSource", trafficSource.name().toLowerCase()).record(requestContext.getLength());
+    } catch (final Exception e) {
+      logger.warn("Error recording content length", e);
+    }
+  }
+}

service/src/test/java/org/whispersystems/textsecuregcm/filters/ContentLengthFilterTest.java

@@ -0,0 +1,32 @@
+/*
+ * Copyright 2021 Signal Messenger, LLC
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+package org.whispersystems.textsecuregcm.filters;
+
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+
+import javax.ws.rs.container.ContainerRequestContext;
+import org.junit.jupiter.api.Test;
+import org.whispersystems.textsecuregcm.metrics.TrafficSource;
+
+class ContentLengthFilterTest {
+
+  @Test
+  void testFilter() throws Exception {
+
+    final ContentLengthFilter contentLengthFilter = new ContentLengthFilter(TrafficSource.WEBSOCKET);
+
+    final ContainerRequestContext requestContext = mock(ContainerRequestContext.class);
+
+    when(requestContext.getLength()).thenReturn(-1);
+    when(requestContext.getLength()).thenReturn(Integer.MAX_VALUE);
+    when(requestContext.getLength()).thenThrow(RuntimeException.class);
+
+    contentLengthFilter.filter(requestContext);
+    contentLengthFilter.filter(requestContext);
+    contentLengthFilter.filter(requestContext);
+  }
+}