✨ feat(health): add RabbitMQ health check functionality

- implement healthSnapshot method to retrieve connection status of active RabbitClients
- create RabbitClientHealthSnapshot data class for health check results
- add RabbitMQMicroserviceHealthContributor for integration with microservice health checks

Author: twisti-dev

gradle.properties

@@ -1,4 +1,4 @@
 kotlin.code.style=official
 kotlin.stdlib.default.dependency=false
 org.gradle.parallel=true
-version=1.6.0
+version=1.6.1

gradle/libs.versions.toml

@@ -1,7 +1,9 @@
 [versions]
-amqp-client = "5.32.0" # Update netty version if needed
-netty = "4.2.15.Final" # Keep in sync with https://github.com/rabbitmq/rabbitmq-java-client/blob/main/pom.xml
+amqp-client = "5.34.0" # Update netty version if needed
+netty = "4.2.16.Final" # Keep in sync with https://github.com/rabbitmq/rabbitmq-java-client/blob/main/pom.xml
+surf-microservice = "2.+"
 
 [libraries]
 amqp-client = { module = "com.rabbitmq:amqp-client", version.ref = "amqp-client" }
-netty-bom = { group = "io.netty", name = "netty-bom", version.ref = "netty" }
+netty-bom = { group = "io.netty", name = "netty-bom", version.ref = "netty" }
+surf-microservice = { group = "dev.slne.surf.microservice", name = "surf-microservice-api-microservice", version.ref = "surf-microservice" }

surf-rabbitmq-common/build.gradle.kts

@@ -8,6 +8,8 @@ dependencies {
     api(projects.surfRabbitmqApi.surfRabbitmqCommonApi)
     api(libs.amqp.client)
 
+    compileOnly(libs.surf.microservice)
+
     api(platform(libs.netty.bom))
 
     // transport classes

surf-rabbitmq-common/src/main/kotlin/dev/slne/surf/rabbitmq/common/connection/RabbitConnectionProvider.kt

@@ -8,13 +8,15 @@ import com.rabbitmq.client.RecoverableConnection
 class RabbitConnectionProvider(
     private val factory: ConnectionFactory,
     val connectionName: String
-): AutoCloseable {
+) : AutoCloseable {
 
     private val lock = Any()
 
     @Volatile
     private var connection: RecoverableConnection? = null
 
+    val isOpen: Boolean get() = connection?.isOpen == true
+
     fun connection(): RecoverableConnection {
         val connection = this.connection
         if (connection != null && connection.isOpen) {

surf-rabbitmq-common/src/main/kotlin/dev/slne/surf/rabbitmq/common/connection/client/RabbitClient.kt

@@ -83,7 +83,6 @@ class RabbitClient private constructor(
         private val activeClients = ConcurrentHashMap<RabbitClient, ActiveClientInfo>()
 
         init {
-
             log.atInfo()
                 .log("Using ${transport.name} for RabbitMQ client")
 
@@ -174,6 +173,17 @@ class RabbitClient private constructor(
             return client
         }
 
+        fun healthSnapshot(): List<RabbitClientHealthSnapshot> {
+            return activeClients.entries
+                .map { (client, info) ->
+                    RabbitClientHealthSnapshot(
+                        connectionName = info.connectionName,
+                        connected = client.connectionProvider.isOpen
+                    )
+                }
+                .sortedBy(RabbitClientHealthSnapshot::connectionName)
+        }
+
         @Blocking
         fun closeSharedResources() {
             val stillActive = activeClients.values.toList()

surf-rabbitmq-common/src/main/kotlin/dev/slne/surf/rabbitmq/common/connection/client/RabbitClientHealthSnapshot.kt

@@ -0,0 +1,6 @@
+package dev.slne.surf.rabbitmq.common.connection.client
+
+data class RabbitClientHealthSnapshot(
+    val connectionName: String,
+    val connected: Boolean
+)

surf-rabbitmq-common/src/main/kotlin/dev/slne/surf/rabbitmq/common/health/RabbitMQMicroserviceHealthContributor.kt

@@ -0,0 +1,31 @@
+package dev.slne.surf.rabbitmq.common.health
+
+import com.google.auto.service.AutoService
+import dev.slne.surf.microservice.api.microservice.health.MicroserviceHealthCheckResult
+import dev.slne.surf.microservice.api.microservice.health.MicroserviceHealthContributor
+import dev.slne.surf.microservice.api.microservice.health.MicroserviceHealthStatus
+import dev.slne.surf.rabbitmq.common.connection.client.RabbitClient
+
+@AutoService(MicroserviceHealthContributor::class)
+class RabbitMQMicroserviceHealthContributor : MicroserviceHealthContributor {
+    override val name: String = "rabbitmq"
+
+    override suspend fun check(): List<MicroserviceHealthCheckResult> {
+        return RabbitClient.healthSnapshot().map { client ->
+            if (client.connected) {
+                MicroserviceHealthCheckResult(
+                    component = name,
+                    instance = client.connectionName,
+                    status = MicroserviceHealthStatus.HEALTHY
+                )
+            } else {
+                MicroserviceHealthCheckResult(
+                    component = name,
+                    instance = client.connectionName,
+                    status = MicroserviceHealthStatus.UNHEALTHY,
+                    message = "RabbitMQ connection is not open."
+                )
+            }
+        }
+    }
+}