max, min and merge operations for MetricSnapshot

2 files changed, 68 insertions, 1 deletions

diff --git a/kamon-core/src/test/scala/kamon/metrics/ActorMetricsSpec.scala b/kamon-core/src/test/scala/kamon/metrics/ActorMetricsSpec.scala
index 91fb3a69..03c1f323 100644
--- a/kamon-core/src/test/scala/kamon/metrics/ActorMetricsSpec.scala
+++ b/kamon-core/src/test/scala/kamon/metrics/ActorMetricsSpec.scala
@@ -39,7 +39,6 @@ class ActorMetricsSpec extends TestKitBase with WordSpecLike with Matchers {
       |}
     """.stripMargin))
 
-
   "the Kamon actor metrics" should {
     "track configured actors" in {
       Kamon(Metrics).subscribe(ActorMetrics, "user/test-tracked-actor", testActor)
diff --git a/kamon-core/src/test/scala/kamon/metrics/MetricSnapshotSpec.scala b/kamon-core/src/test/scala/kamon/metrics/MetricSnapshotSpec.scala
new file mode 100644
index 00000000..1c5a4b21
--- /dev/null
+++ b/kamon-core/src/test/scala/kamon/metrics/MetricSnapshotSpec.scala
@@ -0,0 +1,68 @@
+/*
+ * =========================================================================================
+ * Copyright © 2013 the kamon project <http://kamon.io/>
+ *
+ * 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 kamon.metrics
+
+import org.scalatest.{ Matchers, WordSpec }
+import kamon.metrics.MetricSnapshot.Measurement
+
+class MetricSnapshotSpec extends WordSpec with Matchers {
+
+  "a metric snapshot" should {
+    "support a max operation" in new SnapshotFixtures {
+      snapshotA.max should be(17)
+      snapshotB.max should be(10)
+    }
+
+    "support a min operation" in new SnapshotFixtures {
+      snapshotA.min should be(1)
+      snapshotB.min should be(2)
+    }
+
+    "be able to merge with other snapshot" in new SnapshotFixtures {
+      val merged = snapshotA.merge(snapshotB)
+
+      merged.min should be(1)
+      merged.max should be(17)
+      merged.numberOfMeasurements should be(200)
+      merged.measurementLevels.map(_.value) should contain inOrderOnly (1, 2, 4, 5, 7, 10, 17)
+    }
+
+    "be able to merge with empty snapshots" in new SnapshotFixtures {
+      snapshotA.merge(emptySnapshot) should be(snapshotA)
+    }
+
+  }
+
+  trait SnapshotFixtures {
+    val emptySnapshot = DefaultMetricSnapshot(0, Vector.empty)
+
+    val snapshotA = DefaultMetricSnapshot(100, Vector(
+      Measurement(1, 3),
+      Measurement(2, 15),
+      Measurement(5, 68),
+      Measurement(7, 13),
+      Measurement(17, 1)))
+
+    val snapshotB = DefaultMetricSnapshot(100, Vector(
+      Measurement(2, 6),
+      Measurement(4, 48),
+      Measurement(5, 39),
+      Measurement(10, 7)))
+
+  }
+
+}