Add monitoring/metrics/contrib package to Nomulus release

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=150007228

javatests/google/registry/monitoring/metrics/contrib/EventMetricSubjectTest.java

@@ -0,0 +1,120 @@
+// Copyright 2017 The Nomulus Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package google.registry.monitoring.metrics.contrib;
+
+import static com.google.common.truth.Truth.assertThat;
+import static google.registry.monitoring.metrics.contrib.EventMetricSubject.assertThat;
+import static org.junit.Assert.fail;
+
+import com.google.common.collect.ImmutableSet;
+import google.registry.monitoring.metrics.EventMetric;
+import google.registry.monitoring.metrics.LabelDescriptor;
+import google.registry.monitoring.metrics.MetricRegistryImpl;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
+
+@RunWith(JUnit4.class)
+public class EventMetricSubjectTest {
+
+  private static final ImmutableSet<LabelDescriptor> LABEL_DESCRIPTORS =
+      ImmutableSet.of(
+          LabelDescriptor.create("species", "Sheep Species"),
+          LabelDescriptor.create("color", "Sheep Color"));
+
+  private static final EventMetric metric =
+      MetricRegistryImpl.getDefault()
+          .newEventMetric(
+              "/test/event/sheep",
+              "Sheep Latency",
+              "sheeplatency",
+              LABEL_DESCRIPTORS,
+              EventMetric.DEFAULT_FITTER);
+
+  @Before
+  public void before() {
+    metric.reset();
+    metric.record(2.5, "Domestic", "Green");
+    metric.record(10, "Bighorn", "Blue");
+  }
+
+  @Test
+  public void testWrongNumberOfLabels_fails() {
+    try {
+      assertThat(metric).hasAnyValueForLabels("Domestic");
+      fail("Expected assertion error");
+    } catch (AssertionError e) {
+      assertThat(e)
+          .hasMessageThat()
+          .isEqualTo(
+              "Not true that </test/event/sheep> has a value for labels <Domestic>."
+              + " It has labeled values <[Bighorn:Blue =>"
+              + " {[4.0..16.0)=1}, Domestic:Green => {[1.0..4.0)=1}]>");
+    }
+  }
+
+  @Test
+  public void testDoesNotHaveWrongNumberOfLabels_succeeds() {
+    assertThat(metric).doesNotHaveAnyValueForLabels("Domestic");
+  }
+
+  @Test
+  public void testHasAnyValueForLabels_success() {
+    assertThat(metric)
+        .hasAnyValueForLabels("Domestic", "Green")
+        .and()
+        .hasAnyValueForLabels("Bighorn", "Blue")
+        .and()
+        .hasNoOtherValues();
+  }
+
+  @Test
+  public void testDoesNotHaveValueForLabels_success() {
+    assertThat(metric).doesNotHaveAnyValueForLabels("Domestic", "Blue");
+  }
+
+  @Test
+  public void testDoesNotHaveValueForLabels_failure() {
+    try {
+      assertThat(metric).doesNotHaveAnyValueForLabels("Domestic", "Green");
+      fail("Expected assertion error");
+    } catch (AssertionError e) {
+      assertThat(e)
+          .hasMessageThat()
+          .isEqualTo(
+              "Not true that </test/event/sheep> has no value for labels <Domestic:Green>."
+              + " It has a value of <{[1.0..4.0)=1}>");
+    }
+  }
+
+  @Test
+  public void testUnexpectedValue_failure() {
+    try {
+      assertThat(metric)
+          .hasAnyValueForLabels("Domestic", "Green")
+          .and()
+          .hasNoOtherValues();
+      fail("Expected assertion error");
+    } catch (AssertionError e) {
+      assertThat(e)
+          .hasMessageThat()
+          .isEqualTo(
+              "Not true that </test/event/sheep> has <no other nondefault values>."
+              + " It has labeled values <[Bighorn:Blue =>"
+              + " {[4.0..16.0)=1}, Domestic:Green => {[1.0..4.0)=1}]>");
+    }
+  }
+}