Created a test mocking class for namespaced metric to be used to create metrics inside, for example, the queue reader client

Author: andsel

logstash-core/src/test/java/org/logstash/ext/JrubyMemoryReadClientExtTest.java

@@ -28,6 +28,8 @@
 import org.junit.Test;
 import org.logstash.RubyTestBase;
 import org.logstash.execution.QueueBatch;
+import org.logstash.instrument.metrics.AbstractNamespacedMetricExt;
+import org.logstash.instrument.metrics.MockNamespacedMetric;
 
 import static org.hamcrest.CoreMatchers.is;
 import static org.hamcrest.MatcherAssert.assertThat;
@@ -40,11 +42,14 @@ public final class JrubyMemoryReadClientExtTest extends RubyTestBase {
     @Test
     @SuppressWarnings("deprecation")
     public void testInflightBatchesTracking() throws InterruptedException, IOException {
-        final BlockingQueue<JrubyEventExtLibrary.RubyEvent> queue =
-            new ArrayBlockingQueue<>(10);
-        final JrubyMemoryReadClientExt client =
-            JrubyMemoryReadClientExt.create(queue, 5, 50);
+        final BlockingQueue<JrubyEventExtLibrary.RubyEvent> queue = new ArrayBlockingQueue<>(10);
+        final JrubyMemoryReadClientExt client = JrubyMemoryReadClientExt.create(queue, 5, 50);
+
         final ThreadContext context = client.getRuntime().getCurrentContext();
+
+        AbstractNamespacedMetricExt metric = MockNamespacedMetric.create();
+        client.setPipelineMetric(metric);
+
         final QueueBatch batch = client.readBatch();
         final RubyHash inflight = client.rubyGetInflightBatches(context);
         assertThat(inflight.size(), is(1));

logstash-core/src/test/java/org/logstash/instrument/metrics/MetricTypeTest.java

@@ -39,7 +39,7 @@ public class MetricTypeTest {
      * just duplicates the code, but should cause a developer to think twice if they are changing the public contract.
      */
     @Test
-    public void ensurePassivity(){
+    public void ensurePassivity() {
         Map<MetricType, String> nameMap = new HashMap<>(EnumSet.allOf(MetricType.class).size());
         nameMap.put(MetricType.COUNTER_LONG, "counter/long");
         nameMap.put(MetricType.COUNTER_DECIMAL, "counter/decimal");
@@ -51,6 +51,7 @@ public void ensurePassivity(){
         nameMap.put(MetricType.GAUGE_UNKNOWN, "gauge/unknown");
         nameMap.put(MetricType.GAUGE_RUBYHASH, "gauge/rubyhash");
         nameMap.put(MetricType.GAUGE_RUBYTIMESTAMP, "gauge/rubytimestamp");
+        nameMap.put(MetricType.HISTOGRAM_LONG, "histogram/long");
         nameMap.put(MetricType.FLOW_RATE, "flow/rate");
 
         //ensure we are testing all of the enumerations

logstash-core/src/test/java/org/logstash/instrument/metrics/MockNamespacedMetric.java

@@ -0,0 +1,108 @@
+package org.logstash.instrument.metrics;
+
+import org.jruby.Ruby;
+import org.jruby.RubyArray;
+import org.jruby.RubyClass;
+import org.jruby.RubySymbol;
+import org.jruby.runtime.Block;
+import org.jruby.runtime.ThreadContext;
+import org.jruby.runtime.builtin.IRubyObject;
+import org.logstash.RubyUtil;
+import org.logstash.instrument.metrics.counter.LongCounter;
+import org.logstash.instrument.metrics.histogram.HistogramMetric;
+import org.logstash.instrument.metrics.timer.TimerMetric;
+
+import java.util.Objects;
+
+/**
+ * Trivial implementation of AbstractNamespacedMetricExt where each abstract creation
+ * metric is implemented by instantiating a newly fresh metric object.
+ * */
+@SuppressWarnings({"rawtypes", "serializable"})
+public class MockNamespacedMetric extends AbstractNamespacedMetricExt {
+
+    private static final long serialVersionUID = -6507123659910450215L;
+
+    public static MockNamespacedMetric create() {
+        return new MockNamespacedMetric(RubyUtil.RUBY, RubyUtil.NAMESPACED_METRIC_CLASS);
+    }
+
+    MockNamespacedMetric(final Ruby runtime, final RubyClass metaClass) {
+        super(runtime, metaClass);
+    }
+
+    @Override
+    protected IRubyObject getGauge(ThreadContext context, IRubyObject key, IRubyObject value) {
+        return null;
+    }
+
+    @Override
+    protected RubyArray getNamespaceName(ThreadContext context) {
+        return null;
+    }
+
+    @Override
+    protected IRubyObject getCounter(ThreadContext context, IRubyObject key) {
+        Objects.requireNonNull(key);
+        requireRubySymbol(key, "key");
+        return RubyUtil.toRubyObject(new LongCounter(key.asJavaString()));
+    }
+
+    @Override
+    protected IRubyObject getTimer(ThreadContext context, IRubyObject key) {
+        Objects.requireNonNull(key);
+        requireRubySymbol(key, "key");
+//        return RubyUtil.toRubyObject(TimerMetric.create("test_timer"));
+        return RubyUtil.toRubyObject(TimerMetric.create(key.asJavaString()));
+    }
+
+    @Override
+    protected IRubyObject getHistogram(ThreadContext context, IRubyObject key) {
+        Objects.requireNonNull(key);
+        requireRubySymbol(key, "key");
+
+//        HistogramMetric metric = new HistogramMetric("test_batch_metric");
+        return RubyUtil.toRubyObject(new HistogramMetric(key.asJavaString()));
+    }
+
+    @Override
+    protected IRubyObject doTime(ThreadContext context, IRubyObject key, Block block) {
+        return null;
+    }
+
+    @Override
+    protected IRubyObject doReportTime(ThreadContext context, IRubyObject key, IRubyObject duration) {
+        return null;
+    }
+
+    @Override
+    protected IRubyObject doIncrement(ThreadContext context, IRubyObject[] args) {
+        return null;
+    }
+
+    @Override
+    protected IRubyObject doDecrement(ThreadContext context, IRubyObject[] args) {
+        return null;
+    }
+
+    @Override
+    public AbstractMetricExt getMetric() {
+        return NullMetricExt.create();
+    }
+
+    @Override
+    protected AbstractNamespacedMetricExt createNamespaced(ThreadContext context, IRubyObject name) {
+        return null;
+    }
+
+    @Override
+    protected IRubyObject getCollector(ThreadContext context) {
+        return null;
+    }
+
+    private static void requireRubySymbol(IRubyObject value, String paramName) {
+        if (!(value instanceof RubySymbol)) {
+            throw new IllegalArgumentException(paramName + " must be a RubySymbol instead was: " + value.getClass());
+        }
+    }
+}