1 files changed, 92 insertions, 0 deletions
diff --git a/kamon-core/src/main/scala/kamon/http/HttpServerMetrics.scala b/kamon-core/src/main/scala/kamon/http/HttpServerMetrics.scala
new file mode 100644
index 00000000..3773e7d8
--- /dev/null
+++ b/kamon-core/src/main/scala/kamon/http/HttpServerMetrics.scala
@@ -0,0 +1,92 @@
+package kamon.http
+
+import akka.actor.ActorSystem
+import com.typesafe.config.Config
+import kamon.metric.instrument.Counter
+import kamon.metric._
+
+import scala.collection.concurrent.TrieMap
+
+object HttpServerMetrics extends MetricGroupIdentity {
+  val name: String = "http-server-metrics-recorder"
+  val category = new MetricGroupCategory {
+    val name: String = "http-server"
+  }
+
+  type TraceName = String
+  type StatusCode = String
+
+  case class CountPerStatusCode(statusCode: String) extends MetricIdentity {
+    def name: String = statusCode
+  }
+
+  case class TraceCountPerStatus(traceName: TraceName, statusCode: StatusCode) extends MetricIdentity {
+    def name: String = traceName + "_" + statusCode
+  }
+
+  class HttpServerMetricsRecorder extends MetricGroupRecorder {
+
+    private val counters = TrieMap[StatusCode, Counter]()
+    private val countersPerTrace = TrieMap[TraceName, TrieMap[StatusCode, Counter]]()
+
+    def recordResponse(statusCode: StatusCode): Unit = recordResponse(statusCode, 1L)
+
+    def recordResponse(statusCode: StatusCode, count: Long): Unit =
+      counters.getOrElseUpdate(statusCode, Counter()).increment(count)
+
+    def recordResponse(traceName: TraceName, statusCode: StatusCode): Unit = recordResponse(traceName, statusCode, 1L)
+
+    def recordResponse(traceName: TraceName, statusCode: StatusCode, count: Long): Unit = {
+      recordResponse(statusCode, count)
+      countersPerTrace.getOrElseUpdate(traceName, TrieMap()).getOrElseUpdate(statusCode, Counter()).increment(count)
+    }
+
+    def collect(context: CollectionContext): HttpServerMetricsSnapshot = {
+      val countsPerStatusCode = counters.map {
+        case (statusCode, counter) ⇒ (statusCode, counter.collect(context))
+      }.toMap
+
+      val countsPerTraceAndStatus = countersPerTrace.map {
+        case (traceName, countsPerStatus) ⇒
+          (traceName, countsPerStatus.map { case (statusCode, counter) ⇒ (statusCode, counter.collect(context)) }.toMap)
+      }.toMap
+
+      HttpServerMetricsSnapshot(countsPerStatusCode, countsPerTraceAndStatus)
+    }
+
+    def cleanup: Unit = {}
+  }
+
+  case class HttpServerMetricsSnapshot(countsPerStatusCode: Map[StatusCode, Counter.Snapshot],
+      countsPerTraceAndStatusCode: Map[TraceName, Map[StatusCode, Counter.Snapshot]]) extends MetricGroupSnapshot {
+
+    type GroupSnapshotType = HttpServerMetricsSnapshot
+
+    def merge(that: HttpServerMetricsSnapshot, context: CollectionContext): HttpServerMetricsSnapshot = {
+      val combinedCountsPerStatus = combineMaps(countsPerStatusCode, that.countsPerStatusCode)((l, r) ⇒ l.merge(r, context))
+      val combinedCountsPerTraceAndStatus = combineMaps(countsPerTraceAndStatusCode, that.countsPerTraceAndStatusCode) {
+        (leftCounts, rightCounts) ⇒ combineMaps(leftCounts, rightCounts)((l, r) ⇒ l.merge(r, context))
+      }
+      HttpServerMetricsSnapshot(combinedCountsPerStatus, combinedCountsPerTraceAndStatus)
+    }
+
+    def metrics: Map[MetricIdentity, MetricSnapshot] = {
+      countsPerStatusCode.map {
+        case (statusCode, count) ⇒ (CountPerStatusCode(statusCode), count)
+      } ++ {
+        for (
+          (traceName, countsPerStatus) ← countsPerTraceAndStatusCode;
+          (statusCode, count) ← countsPerStatus
+        ) yield (TraceCountPerStatus(traceName, statusCode), count)
+      }
+    }
+  }
+
+  val Factory = new MetricGroupFactory {
+    type GroupRecorder = HttpServerMetricsRecorder
+
+    def create(config: Config, system: ActorSystem): HttpServerMetricsRecorder =
+      new HttpServerMetricsRecorder()
+  }
+
+}
+\ No newline at end of file