Add support for reporting metrics to signalfx (#129)

service/src/main/java/org/whispersystems/textsecuregcm/metrics/SignalSignalfxReporterFactory.java

@@ -0,0 +1,33 @@
+package org.whispersystems.textsecuregcm.metrics;
+
+import com.amazonaws.util.EC2MetadataUtils;
+import com.codahale.metrics.MetricRegistry;
+import com.codahale.metrics.ScheduledReporter;
+import com.fasterxml.jackson.annotation.JsonProperty;
+import com.fasterxml.jackson.annotation.JsonTypeName;
+import com.signalfx.codahale.reporter.SignalFxReporter;
+import com.signalfx.metrics.auth.StaticAuthToken;
+import io.dropwizard.metrics.BaseReporterFactory;
+
+import javax.validation.constraints.NotEmpty;
+
+@JsonTypeName("signalsignalfx")
+public class SignalSignalfxReporterFactory extends BaseReporterFactory {
+
+  @JsonProperty
+  @NotEmpty
+  private String authToken = null;
+
+  @JsonProperty
+  @NotEmpty
+  private String environment = null;
+
+  public ScheduledReporter build(MetricRegistry registry) {
+    return new SignalFxReporter.Builder(registry, new StaticAuthToken(authToken), EC2MetadataUtils.getInstanceId())
+            .addDimension("environment", environment)
+            .setFilter(getFilter())
+            .setDurationUnit(getDurationUnit())
+            .setRateUnit(getRateUnit())
+            .build();
+  }
+}