fix: Fix counting "lost" bridges. (#869)

* fix: Fix counting "lost" bridges.

* test: Add a unit test for "lost bridges".

Author: bgrozev

src/main/kotlin/org/jitsi/jicofo/bridge/BridgeSelector.kt

@@ -75,6 +75,7 @@ class BridgeSelector @JvmOverloads constructor(
      * The number of bridges which disconnected without going into graceful shutdown first.
      */
     private val lostBridges = AtomicInteger()
+    fun lostBridges() = lostBridges.get()
 
     /**
      * Adds a bridge to this selector, or if a bridge with the given JID
@@ -110,7 +111,7 @@ class BridgeSelector @JvmOverloads constructor(
     fun removeJvbAddress(bridgeJid: Jid) {
         logger.info("Removing JVB: $bridgeJid")
         bridges.remove(bridgeJid)?.let {
-            if (it.isInGracefulShutdown) {
+            if (!it.isInGracefulShutdown) {
                 lostBridges.incrementAndGet()
             }
             eventEmitter.fireEvent { bridgeRemoved(it) }

src/test/java/mock/util/TestConference.java

@@ -74,7 +74,7 @@ private void createJvbAndConference(String serverName, EntityBareJid roomName)
         mockBridge.start();
 
         Bridge bridge = harness.jicofoServices.getBridgeSelector().addJvbAddress(bridgeJid);
-        BridgeTestKt.setStats(bridge, 0.0, "region", "version", true /* colibri2 */);
+        BridgeTestKt.setStats(bridge, 0.0, "region", "version", true /* colibri2 */, false);
 
         createConferenceRoom(roomName);
     }

src/test/kotlin/org/jitsi/jicofo/bridge/BridgeSelectorTest.kt

@@ -148,6 +148,23 @@ class BridgeSelectorTest : ShouldSpec() {
             val jvb2 = selector.addJvbAddress(jid2).apply { setStats(stress = 0.9) }
             selector.selectBridge() shouldBe jvb2
         }
+        context("Lost bridges stats") {
+            val selector = BridgeSelector(clock)
+            selector.lostBridges() shouldBe 0
+
+            val jvb1 = selector.addJvbAddress(jid1)
+            selector.lostBridges() shouldBe 0
+
+            should("Increment the lost bridges stat when a bridge goes away") {
+                selector.removeJvbAddress(jvb1.jid)
+                selector.lostBridges() shouldBe 1
+            }
+            should("Not increment the lost bridges stat when a bridge in graceful-shutdown goes away") {
+                jvb1.setStats(gracefulShutdown = true)
+                selector.removeJvbAddress(jvb1.jid)
+                selector.lostBridges() shouldBe 0
+            }
+        }
     }
 }
 

src/test/kotlin/org/jitsi/jicofo/bridge/BridgeTest.kt

@@ -126,7 +126,8 @@ fun Bridge.setStats(
     stress: Double? = null,
     region: String? = null,
     version: String? = null,
-    colibri2: Boolean = true
+    colibri2: Boolean = true,
+    gracefulShutdown: Boolean = false
 ) = setStats(
     ColibriStatsExtension().apply {
         stress?.let { addStat(ColibriStatsExtension.Stat("stress_level", it)) }
@@ -136,5 +137,6 @@ fun Bridge.setStats(
         }
         version?.let { addStat(ColibriStatsExtension.Stat("version", version)) }
         if (colibri2) addStat("colibri2", "true")
+        if (gracefulShutdown) addStat(ColibriStatsExtension.SHUTDOWN_IN_PROGRESS, "true")
     }
 )