Merge pull request #136 from Tradeshift/vizog-metric_name

Add additional tags for MaterializerActor

ts-reaktive-actors/src/main/java/com/tradeshift/reaktive/materialize/MaterializerActor.java

@@ -61,7 +61,7 @@ public abstract class MaterializerActor<E> extends AbstractPersistentActor {
     protected final LoggingAdapter log = Logging.getLogger(getContext().getSystem(), this);
     private final MaterializerMetrics metrics = new MaterializerMetrics(
         // Turn CamelCase to camel-case.
-        getClass().getSimpleName().replaceAll("([a-z])([A-Z]+)", "$1-$2").toLowerCase());
+        getClass().getSimpleName().replaceAll("([a-z])([A-Z]+)", "$1-$2").toLowerCase(), getAdditionalMetricTags());
     private final FiniteDuration rollback;
     private final FiniteDuration updateAccuracy;
     private final FiniteDuration restartDelay;
@@ -434,6 +434,14 @@ private CompletionStage<Done> persistSequential(int workerIndex, Seq<E> seq) {
      */
     public abstract Instant timestampOf(E envelope);
 
+    /**
+     * @return the custom tags which will be attached to materializer metrics reported by Kamon.
+     * By default, only the class name is attached as a tag in Kamon metrics and there are no custom tags.
+     */
+    protected Map<String, String> getAdditionalMetricTags() {
+        return HashMap.empty();
+    }
+
     /**
      * Message that can be sent to this actor to start a secondary re-import of certain UUIDs.
      * The main import stream will keep running while the re-import is underway.

ts-reaktive-actors/src/main/java/com/tradeshift/reaktive/materialize/MaterializerMetrics.java

@@ -1,8 +1,6 @@
 package com.tradeshift.reaktive.materialize;
 
-import java.util.Map;
-
-import io.vavr.collection.HashMap;
+import io.vavr.collection.Map;
 import kamon.Kamon;
 import kamon.metric.Counter;
 import kamon.metric.CounterMetric;
@@ -13,7 +11,7 @@
 import kamon.metric.MeasurementUnit;
 
 public class MaterializerMetrics {
-    private final HashMap<String, String> baseTags;
+    private final Map<String, String> baseTags;
     private final CounterMetric events;
     private final Counter restarts;
     private final Gauge reimportRemaining;
@@ -26,9 +24,9 @@ public class MaterializerMetrics {
     /** The duration, milliseconds, of materializing a single event */
     private final HistogramMetric materializationDuration;
 
-    public MaterializerMetrics(String name) {
-        baseTags = HashMap.of("journal-materializer", name);
-        Map<String, String> tags = baseTags.toJavaMap();
+    public MaterializerMetrics(String name, Map<String, String> additionalTags) {
+        baseTags = additionalTags.put("journal-materializer", name);
+        java.util.Map<String, String> tags = baseTags.toJavaMap();
         this.events = Kamon.counter("journal-materializer.events");
         this.restarts = Kamon.counter("journal-materializer.restarts").refine(tags);
         this.reimportRemaining = Kamon.gauge("journal-materializer.reimport-remaining", MeasurementUnit.time().milliseconds()).refine(tags);