Add metrics for active connections count

* Fix and refactor gauges tests in MicrometerMetricsTests
  as they were not executing
* Fix client disconnection handler in NettyTcpServer
* Add metrics gauge and counters required to measure active connections

Change-Id: I5620d398525c6859679cd5a49dc55a9fefd8b592
Signed-off-by: Jakub Dudycz <jakub.dudycz@nokia.com>
Issue-ID: DCAEGEN2-1041

2 files changed, 17 insertions, 12 deletions

diff --git a/sources/hv-collector-ct/src/test/kotlin/org/onap/dcae/collectors/veshv/tests/component/MetricsSpecification.kt b/sources/hv-collector-ct/src/test/kotlin/org/onap/dcae/collectors/veshv/tests/component/MetricsSpecification.kt
index 572cc796..f457aeaf 100644
--- a/sources/hv-collector-ct/src/test/kotlin/org/onap/dcae/collectors/veshv/tests/component/MetricsSpecification.kt
+++ b/sources/hv-collector-ct/src/test/kotlin/org/onap/dcae/collectors/veshv/tests/component/MetricsSpecification.kt
@@ -175,7 +175,6 @@ object MetricsSpecification : Spek({
     }
 
     describe("clients rejected metrics") {
-
         given("rejection causes") {
             mapOf(
                     ClientRejectionCause.PAYLOAD_SIZE_EXCEEDED_IN_MESSAGE to
@@ -192,7 +191,7 @@ object MetricsSpecification : Spek({
                         assertThat(metrics.clientRejectionCause.size)
                                 .describedAs("metrics were notified with only one rejection cause")
                                 .isOne()
-                        assertThat(metrics.clientRejectionCause.get(cause))
+                        assertThat(metrics.clientRejectionCause[cause])
                                 .describedAs("metrics were notified only once with correct client rejection cause")
                                 .isOne()
                     }
diff --git a/sources/hv-collector-ct/src/test/kotlin/org/onap/dcae/collectors/veshv/tests/fakes/metrics.kt b/sources/hv-collector-ct/src/test/kotlin/org/onap/dcae/collectors/veshv/tests/fakes/metrics.kt
index a27d167a..8573d86f 100644
--- a/sources/hv-collector-ct/src/test/kotlin/org/onap/dcae/collectors/veshv/tests/fakes/metrics.kt
+++ b/sources/hv-collector-ct/src/test/kotlin/org/onap/dcae/collectors/veshv/tests/fakes/metrics.kt
@@ -21,12 +21,11 @@ package org.onap.dcae.collectors.veshv.tests.fakes
 
 import org.onap.dcae.collectors.veshv.boundary.Metrics
 import org.onap.dcae.collectors.veshv.domain.WireFrameMessage
+import org.onap.dcae.collectors.veshv.model.ClientRejectionCause
 import org.onap.dcae.collectors.veshv.model.MessageDropCause
 import org.onap.dcae.collectors.veshv.model.RoutedMessage
 import java.time.Duration
 import java.time.Instant
-import org.onap.dcae.collectors.veshv.model.ClientRejectionCause
-import java.util.concurrent.ConcurrentHashMap
 import kotlin.test.fail
 
 /**
@@ -35,14 +34,15 @@ import kotlin.test.fail
  */
 class FakeMetrics : Metrics {
 
-    var bytesReceived: Int = 0 ; private set
-    var messageBytesReceived: Int = 0 ; private set
-    var messagesDroppedCount: Int = 0 ; private set
-    var lastProcessingTimeMicros: Double = -1.0 ; private set
-    private val messagesDroppedCause: MutableMap<MessageDropCause, Int> = ConcurrentHashMap()
-    var messagesSentCount: Int = 0 ; private set
-    val messagesSentToTopic: MutableMap<String, Int> = ConcurrentHashMap()
-    var clientRejectionCause = mutableMapOf<ClientRejectionCause, Int>() ; private set
+    var bytesReceived: Int = 0; private set
+    var messageBytesReceived: Int = 0; private set
+    var messagesDroppedCount: Int = 0; private set
+    var lastProcessingTimeMicros: Double = -1.0; private set
+    var messagesSentCount: Int = 0; private set
+    var clientRejectionCause = mutableMapOf<ClientRejectionCause, Int>(); private set
+
+    private val messagesSentToTopic = mutableMapOf<String, Int>()
+    private val messagesDroppedCause = mutableMapOf<MessageDropCause, Int>()
 
     override fun notifyBytesReceived(size: Int) {
         bytesReceived += size
@@ -69,6 +69,12 @@ class FakeMetrics : Metrics {
         clientRejectionCause.compute(cause) { k, _ -> clientRejectionCause[k]?.inc() ?: 1 }
     }
 
+    override fun notifyClientDisconnected() {
+    }
+
+    override fun notifyClientConnected() {
+    }
+
     fun messagesOnTopic(topic: String) =
             messagesSentToTopic[topic] ?: fail("No messages were sent to topic $topic")