Customizable Transformers

README.md

@@ -64,6 +64,53 @@ NewRelicReporter reporter = NewRelicReporter.build(metricRegistry, metricBatchSe
         .commonAttributes(commonAttributes)
         .build();
 
+reporter.start(15, TimeUnit.SECONDS);
+```
+## Customizing Reported Metrics
+If you would like to customize the way metric names or attributes are reported to New Relic, you will want to supply
+customizers to the `NewRelicReporterBuilder`.
+
+Consider metrics with tags encoded in their names, formatted like so: `"metricName[tag:value,othertag:othervalue]"`,
+you might set up a reporter to report the metric name as `metricName` and add merge of the key/value pairs in `name`
+with the `commonAttributes`. 
+
+```
+MetricRegistry metricRegistry = new MetricRegistry(); // If you're already using dropwizard-metrics you may already have one of these.
+...
+String apiKey = "<YOUR_SECRET_API_KEY>";
+MetricBatchSender metricBatchSender = MetricBatchSenderFactory
+                .fromHttpImplementation(OkHttpPoster::new)
+                .createBatchSender(apiKey);
+
+Attributes commonAttributes = new Attributes()
+            .put("host", InetAddress.getLocalHost().getHostName())
+            .put("appName", "Your Application Name Here")
+            .put("other", "any other common attributes you wish");
+
+MetricAttributeCustomizer mergeAttributesFromTaggedMetricName =
+    (name, metric, attributes) -> {
+      Attributes tagsAsAttributes = new Attributes();
+
+      // get a stream of each tag:value pair within the square brackets of name and add
+      // each pair to the tagsAsAttributes Attributes object
+      Stream.of(name.substring(name.indexOf('['), name.indexOf(']')).split(","))
+          .forEach(
+              str -> {
+                String[] keyValuePair = str.split(":");
+
+                tagsAsAttributes.put(keyValuePair[0], keyValuePair[1]);
+              });
+
+      return tagsAsAttributes.putAll(attributes);
+    };
+
+NewRelicReporter reporter = NewRelicReporter.build(metricRegistry, metricBatchSender)
+        .commonAttributes(commonAttributes)
+        // customizer to strip encoded tags from metric name
+        .metricNameCustomizer(name -> name.substring(0, name.indexOf('[')))
+        .metricAttributeCustomizer(mergeAttributesFromTaggedMetricName)
+        .build();
+
 reporter.start(15, TimeUnit.SECONDS);
 ```
 

src/main/java/com/codahale/metrics/newrelic/NewRelicReporterBuilder.java

@@ -16,6 +16,8 @@
 import com.codahale.metrics.newrelic.transformer.HistogramTransformer;
 import com.codahale.metrics.newrelic.transformer.MeterTransformer;
 import com.codahale.metrics.newrelic.transformer.TimerTransformer;
+import com.codahale.metrics.newrelic.transformer.customizer.MetricAttributesCustomizer;
+import com.codahale.metrics.newrelic.transformer.customizer.MetricNameCustomizer;
 import com.codahale.metrics.newrelic.util.TimeTracker;
 import com.newrelic.telemetry.Attributes;
 import com.newrelic.telemetry.TelemetryClient;
@@ -35,6 +37,8 @@ public class NewRelicReporterBuilder {
   private TimeUnit durationUnit = TimeUnit.MILLISECONDS;
   private Attributes commonAttributes = new Attributes();
   private Set<MetricAttribute> disabledMetricAttributes = Collections.emptySet();
+  private MetricNameCustomizer nameCustomizer = MetricNameCustomizer.DEFAULT;
+  private MetricAttributesCustomizer attributeCustomizer = MetricAttributesCustomizer.DEFAULT;
 
   public static NewRelicReporterBuilder forRegistry(
       MetricRegistry registry, MetricBatchSender metricBatchSender) {
@@ -77,6 +81,17 @@ public NewRelicReporterBuilder disabledMetricAttributes(
     return this;
   }
 
+  public NewRelicReporterBuilder metricNameCustomizer(MetricNameCustomizer nameCustomizer) {
+    this.nameCustomizer = nameCustomizer;
+    return this;
+  }
+
+  public NewRelicReporterBuilder metricAttributeCustomizer(
+      MetricAttributesCustomizer attributeCustomizer) {
+    this.attributeCustomizer = attributeCustomizer;
+    return this;
+  }
+
   public NewRelicReporter build() {
     long rateFactor = rateUnit.toSeconds(1);
     double durationFactor = durationUnit.toNanos(1);
@@ -85,12 +100,21 @@ public NewRelicReporter build() {
 
     TimeTracker timeTracker = new TimeTracker(Clock.defaultClock());
     MeterTransformer meterTransformer =
-        MeterTransformer.build(timeTracker, rateFactor, metricAttributePredicate);
+        MeterTransformer.build(
+            timeTracker, rateFactor, metricAttributePredicate, nameCustomizer, attributeCustomizer);
     TimerTransformer timerTransformer =
-        TimerTransformer.build(timeTracker, rateFactor, durationFactor, metricAttributePredicate);
-    GaugeTransformer gaugeTransformer = new GaugeTransformer();
-    CounterTransformer counterTransformer = new CounterTransformer();
-    HistogramTransformer histogramTransformer = HistogramTransformer.build(timeTracker);
+        TimerTransformer.build(
+            timeTracker,
+            rateFactor,
+            durationFactor,
+            metricAttributePredicate,
+            nameCustomizer,
+            attributeCustomizer);
+    GaugeTransformer gaugeTransformer = new GaugeTransformer(nameCustomizer, attributeCustomizer);
+    CounterTransformer counterTransformer =
+        new CounterTransformer(nameCustomizer, attributeCustomizer);
+    HistogramTransformer histogramTransformer =
+        HistogramTransformer.build(timeTracker, nameCustomizer, attributeCustomizer);
 
     return new NewRelicReporter(
         timeTracker,

src/main/java/com/codahale/metrics/newrelic/transformer/CounterTransformer.java

@@ -11,26 +11,49 @@
 
 import com.codahale.metrics.Clock;
 import com.codahale.metrics.Counter;
+import com.codahale.metrics.newrelic.transformer.customizer.MetricAttributesCustomizer;
+import com.codahale.metrics.newrelic.transformer.customizer.MetricNameCustomizer;
 import com.newrelic.telemetry.Attributes;
 import com.newrelic.telemetry.metrics.Gauge;
 import com.newrelic.telemetry.metrics.Metric;
 import java.util.Collection;
+import java.util.Objects;
 
 public class CounterTransformer implements DropWizardMetricTransformer<Counter> {
 
   private final Clock clock;
+  private final MetricNameCustomizer nameCustomizer;
+  private final MetricAttributesCustomizer attributeCustomizer;
 
   public CounterTransformer() {
     this(Clock.defaultClock());
   }
 
+  public CounterTransformer(
+      MetricNameCustomizer nameCustomizer, MetricAttributesCustomizer attributeCustomizer) {
+    this(Clock.defaultClock(), nameCustomizer, attributeCustomizer);
+  }
+
   // exists for testing
   CounterTransformer(Clock clock) {
+    this(clock, MetricNameCustomizer.DEFAULT, MetricAttributesCustomizer.DEFAULT);
+  }
+
+  CounterTransformer(
+      Clock clock,
+      MetricNameCustomizer nameCustomizer,
+      MetricAttributesCustomizer attributeCustomizer) {
     this.clock = clock;
+    this.nameCustomizer = Objects.requireNonNull(nameCustomizer);
+    this.attributeCustomizer = Objects.requireNonNull(attributeCustomizer);
   }
 
   @Override
   public Collection<Metric> transform(String name, Counter counter) {
-    return singleton(new Gauge(name, counter.getCount(), clock.getTime(), new Attributes()));
+    String customizedName = nameCustomizer.customizeMetricName(name);
+    Attributes customizedAttributes =
+        attributeCustomizer.customizeMetricAttributes(name, counter, new Attributes());
+    return singleton(
+        new Gauge(customizedName, counter.getCount(), clock.getTime(), customizedAttributes));
   }
 }

src/main/java/com/codahale/metrics/newrelic/transformer/GaugeTransformer.java

@@ -12,43 +12,69 @@
 
 import com.codahale.metrics.Clock;
 import com.codahale.metrics.Gauge;
+import com.codahale.metrics.newrelic.transformer.customizer.MetricAttributesCustomizer;
+import com.codahale.metrics.newrelic.transformer.customizer.MetricNameCustomizer;
 import com.newrelic.telemetry.Attributes;
 import com.newrelic.telemetry.metrics.Metric;
 import java.util.Collection;
+import java.util.Objects;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 public class GaugeTransformer implements DropWizardMetricTransformer<Gauge> {
 
   private static final Logger LOG = LoggerFactory.getLogger(GaugeTransformer.class);
   private final Clock clock;
+  private final MetricNameCustomizer nameCustomizer;
+  private final MetricAttributesCustomizer attributeCustomizer;
 
   public GaugeTransformer() {
-    this(Clock.defaultClock());
+    this(MetricNameCustomizer.DEFAULT, MetricAttributesCustomizer.DEFAULT);
+  }
+
+  public GaugeTransformer(
+      MetricNameCustomizer nameCustomizer, MetricAttributesCustomizer attributeCustomizer) {
+    this(Clock.defaultClock(), nameCustomizer, attributeCustomizer);
   }
 
   // exists for testing
   public GaugeTransformer(Clock clock) {
+    this(clock, MetricNameCustomizer.DEFAULT, MetricAttributesCustomizer.DEFAULT);
+  }
+
+  public GaugeTransformer(
+      Clock clock,
+      MetricNameCustomizer nameCustomizer,
+      MetricAttributesCustomizer attributeCustomizer) {
     this.clock = clock;
+    this.nameCustomizer = Objects.requireNonNull(nameCustomizer);
+    this.attributeCustomizer = Objects.requireNonNull(attributeCustomizer);
   }
 
   @Override
   public Collection<Metric> transform(String name, Gauge gauge) {
+    String customizedName = nameCustomizer.customizeMetricName(name);
+    Attributes customizedAttributes =
+        attributeCustomizer.customizeMetricAttributes(name, gauge, new Attributes());
     long timestamp = clock.getTime();
     Object gaugeValue = gauge.getValue();
     if (gaugeValue == null) {
-      LOG.debug("Ignoring gauge with null value. Gauge name: {}", name);
+      LOG.debug(
+          "Ignoring gauge with null value. Gauge name: {}, Gauge attributes: {}",
+          customizedName,
+          customizedAttributes);
       return emptySet();
     }
     if (gaugeValue instanceof Number) {
       Metric metric =
           new com.newrelic.telemetry.metrics.Gauge(
-              name, ((Number) gaugeValue).doubleValue(), timestamp, new Attributes());
+              customizedName, ((Number) gaugeValue).doubleValue(), timestamp, customizedAttributes);
       return singleton(metric);
     }
     LOG.debug(
-        "Ignoring gauge [name: {}] with value of type {} (non-numeric gauges are unsupported)",
-        name,
+        "Ignoring gauge [name: {}, Attributes: {}] with value of type {} (non-numeric gauges are unsupported)",
+        customizedName,
+        customizedAttributes,
         gaugeValue.getClass().getName());
     return emptySet();
   }

src/main/java/com/codahale/metrics/newrelic/transformer/HistogramTransformer.java

@@ -11,12 +11,15 @@
 import static java.util.stream.Stream.concat;
 
 import com.codahale.metrics.Histogram;
+import com.codahale.metrics.newrelic.transformer.customizer.MetricAttributesCustomizer;
+import com.codahale.metrics.newrelic.transformer.customizer.MetricNameCustomizer;
 import com.codahale.metrics.newrelic.transformer.interfaces.CountingTransformer;
 import com.codahale.metrics.newrelic.transformer.interfaces.SamplingTransformer;
 import com.codahale.metrics.newrelic.util.TimeTracker;
 import com.newrelic.telemetry.Attributes;
 import com.newrelic.telemetry.metrics.Metric;
 import java.util.Collection;
+import java.util.Objects;
 import java.util.function.Supplier;
 
 public class HistogramTransformer implements DropWizardMetricTransformer<Histogram> {
@@ -25,30 +28,65 @@ public class HistogramTransformer implements DropWizardMetricTransformer<Histogr
 
   private final CountingTransformer countingTransformer;
   private final SamplingTransformer samplingTransformer;
+  private final MetricNameCustomizer nameCustomizer;
+  private final MetricAttributesCustomizer attributeCustomizer;
 
   public static HistogramTransformer build(TimeTracker timeTracker) {
+    return build(timeTracker, MetricNameCustomizer.DEFAULT, MetricAttributesCustomizer.DEFAULT);
+  }
+
+  public static HistogramTransformer build(
+      TimeTracker timeTracker,
+      MetricNameCustomizer nameCustomizer,
+      MetricAttributesCustomizer attributeCustomizer) {
     return new HistogramTransformer(
-        new CountingTransformer(timeTracker), new SamplingTransformer(timeTracker, 1L));
+        new CountingTransformer(timeTracker),
+        new SamplingTransformer(timeTracker, 1L),
+        nameCustomizer,
+        attributeCustomizer);
   }
 
   HistogramTransformer(
-      CountingTransformer countingTransformer, SamplingTransformer samplingTransformer) {
+      CountingTransformer countingTransformer,
+      SamplingTransformer samplingTransformer,
+      MetricNameCustomizer nameCustomizer,
+      MetricAttributesCustomizer attributeCustomizer) {
     this.countingTransformer = countingTransformer;
     this.samplingTransformer = samplingTransformer;
+    this.nameCustomizer = Objects.requireNonNull(nameCustomizer);
+    this.attributeCustomizer = Objects.requireNonNull(attributeCustomizer);
+  }
+
+  HistogramTransformer(
+      CountingTransformer countingTransformer, SamplingTransformer samplingTransformer) {
+    this(
+        countingTransformer,
+        samplingTransformer,
+        MetricNameCustomizer.DEFAULT,
+        MetricAttributesCustomizer.DEFAULT);
   }
 
   @Override
   public Collection<Metric> transform(String name, Histogram histogram) {
-    Collection<Metric> counts = countingTransformer.transform(name, histogram, ATTRIBUTES_SUPPLIER);
+    String customizedName = nameCustomizer.customizeMetricName(name);
+    Supplier<Attributes> customizedAttributeSupplier =
+        () ->
+            attributeCustomizer.customizeMetricAttributes(
+                name, histogram, ATTRIBUTES_SUPPLIER.get());
+
+    Collection<Metric> counts =
+        countingTransformer.transform(customizedName, histogram, customizedAttributeSupplier);
 
     return concat(
             counts.stream(),
-            samplingTransformer.transform(name, histogram, ATTRIBUTES_SUPPLIER).stream())
+            samplingTransformer
+                .transform(customizedName, histogram, customizedAttributeSupplier)
+                .stream())
         .collect(toSet());
   }
 
   @Override
   public void onHistogramRemoved(String name) {
-    countingTransformer.remove(name);
+    countingTransformer.remove(nameCustomizer.customizeMetricName(name));
   }
 }