Support DataDog Reporting.

pom.xml

@@ -114,6 +114,12 @@
             <artifactId>jetty-websocket</artifactId>
             <version>8.1.14.v20131031</version>
         </dependency>
+
+        <dependency>
+            <groupId>org.coursera</groupId>
+            <artifactId>metrics-datadog</artifactId>
+            <version>0.1.5</version>
+        </dependency>
     </dependencies>
 
     <build>

src/main/java/org/whispersystems/textsecuregcm/WhisperServerConfiguration.java

@@ -20,6 +20,7 @@ import com.fasterxml.jackson.annotation.JsonProperty;
 import com.yammer.dropwizard.config.Configuration;
 import com.yammer.dropwizard.db.DatabaseConfiguration;
 import org.whispersystems.textsecuregcm.configuration.ApnConfiguration;
+import org.whispersystems.textsecuregcm.configuration.DataDogConfiguration;
 import org.whispersystems.textsecuregcm.configuration.FederationConfiguration;
 import org.whispersystems.textsecuregcm.configuration.GcmConfiguration;
 import org.whispersystems.textsecuregcm.configuration.GraphiteConfiguration;
@@ -84,6 +85,10 @@ public class WhisperServerConfiguration extends Configuration {
   @JsonProperty
   private GraphiteConfiguration graphite = new GraphiteConfiguration();
 
+  @Valid
+  @JsonProperty
+  private DataDogConfiguration datadog = new DataDogConfiguration();
+
   @Valid
   @JsonProperty
   private WebsocketConfiguration websocket = new WebsocketConfiguration();
@@ -135,4 +140,8 @@ public class WhisperServerConfiguration extends Configuration {
   public GraphiteConfiguration getGraphiteConfiguration() {
     return graphite;
   }
+
+  public DataDogConfiguration getDataDogConfiguration() {
+    return datadog;
+  }
 }

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

@@ -24,6 +24,9 @@ import com.yammer.dropwizard.config.HttpConfiguration;
 import com.yammer.dropwizard.db.DatabaseConfiguration;
 import com.yammer.dropwizard.jdbi.DBIFactory;
 import com.yammer.dropwizard.migrations.MigrationsBundle;
+import com.yammer.metrics.core.Clock;
+import com.yammer.metrics.core.MetricPredicate;
+import com.yammer.metrics.reporting.DatadogReporter;
 import com.yammer.metrics.reporting.GraphiteReporter;
 import net.spy.memcached.MemcachedClient;
 import org.bouncycastle.jce.provider.BouncyCastleProvider;
@@ -164,6 +167,13 @@ public class WhisperServerService extends Service<WhisperServerConfiguration> {
                               config.getGraphiteConfiguration().getHost(),
                               config.getGraphiteConfiguration().getPort());
     }
+
+    if (config.getDataDogConfiguration().isEnabled()) {
+      new DatadogReporter.Builder().withApiKey(config.getDataDogConfiguration().getApiKey())
+                                   .withVmMetricsEnabled(true)
+                                   .build()
+                                   .start(15, TimeUnit.SECONDS);
+    }
   }
 
   private Optional<NexmoSmsSender> initializeNexmoSmsSender(NexmoConfiguration configuration) {

src/main/java/org/whispersystems/textsecuregcm/configuration/DataDogConfiguration.java

@@ -0,0 +1,20 @@
+package org.whispersystems.textsecuregcm.configuration;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+
+public class DataDogConfiguration {
+
+  @JsonProperty
+  private String apiKey;
+
+  @JsonProperty
+  private boolean enabled = false;
+
+  public String getApiKey() {
+    return apiKey;
+  }
+
+  public boolean isEnabled() {
+    return enabled && apiKey != null;
+  }
+}