Added a framework for metrics
Added a metrics framework based on the codahale Metrics
package. ONOS can create a registry and maintain Metrics,
as well as dump out metrics values via a REST API. Unit
tests are include that test the REST APIs. Currently
supports Timers, Counters, Gauges, Meters, and Histograms.
Change-Id: I0f6ed87f889dc7037caf9aefc92e663702c6dda8
diff --git a/src/main/java/net/onrc/onos/core/metrics/MetricsResource.java b/src/main/java/net/onrc/onos/core/metrics/MetricsResource.java
new file mode 100644
index 0000000..64b7996
--- /dev/null
+++ b/src/main/java/net/onrc/onos/core/metrics/MetricsResource.java
@@ -0,0 +1,82 @@
+package net.onrc.onos.core.metrics;
+
+import com.codahale.metrics.Gauge;
+import com.codahale.metrics.MetricRegistry;
+import com.codahale.metrics.Timer;
+import com.codahale.metrics.Counter;
+import com.codahale.metrics.Meter;
+import com.codahale.metrics.Histogram;
+import org.restlet.representation.Representation;
+import org.restlet.resource.Get;
+import org.restlet.resource.ServerResource;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Map;
+
+/**
+ * REST APIs for Metrics objects.
+ */
+public class MetricsResource extends ServerResource {
+
+ /**
+ * REST API to get all of the system's metrics.
+ *
+ * @return a Representation object containing the metrics
+ */
+ @Get("json")
+ @SuppressWarnings("rawtypes")
+ public Representation retrieve() throws Exception {
+ final MetricRegistry registry = OnosMetrics.getMetricsRegistry();
+ final MetricsObjectResource result = new MetricsObjectResource();
+
+ final List<MetricsObjectResource.TimerObjectResource> timers =
+ new ArrayList<>();
+ final List<MetricsObjectResource.GaugeObjectResource> gauges =
+ new ArrayList<>();
+ final List<MetricsObjectResource.CounterObjectResource> counters =
+ new ArrayList<>();
+ final List<MetricsObjectResource.MeterObjectResource> meters =
+ new ArrayList<>();
+ final List<MetricsObjectResource.HistogramObjectResource> histograms =
+ new ArrayList<>();
+
+ for (final Map.Entry<String, Timer> timer :
+ registry.getTimers().entrySet()) {
+ timers.add(new MetricsObjectResource.TimerObjectResource(
+ timer.getKey(), timer.getValue()));
+ }
+ result.setTimers(timers);
+
+ for (final Map.Entry<String, Gauge> gauge :
+ registry.getGauges().entrySet()) {
+ gauges.add(new MetricsObjectResource.GaugeObjectResource(
+ gauge.getKey(), gauge.getValue()));
+ }
+ result.setGauges(gauges);
+
+ for (final Map.Entry<String, Counter> counter :
+ registry.getCounters().entrySet()) {
+ counters.add(new MetricsObjectResource.CounterObjectResource(
+ counter.getKey(), counter.getValue()));
+ }
+ result.setCounters(counters);
+
+ for (final Map.Entry<String, Meter> meter :
+ registry.getMeters().entrySet()) {
+ meters.add(new MetricsObjectResource.MeterObjectResource(
+ meter.getKey(), meter.getValue()));
+ }
+ result.setMeters(meters);
+
+ for (final Map.Entry<String, Histogram> histogram :
+ registry.getHistograms().entrySet()) {
+ histograms.add(new MetricsObjectResource.HistogramObjectResource(
+ histogram.getKey(), histogram.getValue()));
+ }
+ result.setHistograms(histograms);
+
+ return toRepresentation(result, null);
+ }
+
+}