GH-39 Support lifecycle event handlers in annotated routing (Resolve #39

)
javalin · Feb 16, 2024 · f189af5 · f189af5
1 parent 0669eea
commit f189af5
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diff --git a/...cification/src/main/kotlin/io/javalin/community/routing/annotations/RoutingAnnotations.kt b/...cification/src/main/kotlin/io/javalin/community/routing/annotations/RoutingAnnotations.kt
@@ -1,5 +1,6 @@
 package io.javalin.community.routing.annotations
 
+import io.javalin.event.JavalinLifecycleEvent
 import io.javalin.http.HttpStatus
 import kotlin.annotation.AnnotationRetention.RUNTIME
 import kotlin.annotation.AnnotationTarget.CLASS
@@ -18,6 +19,10 @@ annotation class Endpoints(val value: String = "")
 @Target(FUNCTION)
 annotation class ExceptionHandler(val value: KClass<out Exception>)
 
+@Retention(RUNTIME)
+@Target(FUNCTION)
+annotation class LifecycleEventHandler(val lifecycleEvent: JavalinLifecycleEvent)
+
 @Retention(RUNTIME)
 @Target(FUNCTION)
 annotation class Get(val value: String = "", val async: Boolean = false)

diff --git a/...ng-annotated/src/main/kotlin/io/javalin/community/routing/annotations/AnnotatedRouting.kt b/...ng-annotated/src/main/kotlin/io/javalin/community/routing/annotations/AnnotatedRouting.kt
@@ -6,6 +6,13 @@ import io.javalin.community.routing.invokeAsSamWithReceiver
 import io.javalin.community.routing.registerRoute
 import io.javalin.community.routing.sortRoutes
 import io.javalin.config.JavalinConfig
+import io.javalin.event.JavalinLifecycleEvent
+import io.javalin.event.JavalinLifecycleEvent.SERVER_STARTED
+import io.javalin.event.JavalinLifecycleEvent.SERVER_STARTING
+import io.javalin.event.JavalinLifecycleEvent.SERVER_START_FAILED
+import io.javalin.event.JavalinLifecycleEvent.SERVER_STOPPED
+import io.javalin.event.JavalinLifecycleEvent.SERVER_STOPPING
+import io.javalin.event.JavalinLifecycleEvent.SERVER_STOP_FAILED
 import io.javalin.http.BadRequestResponse
 import io.javalin.http.Context
 import io.javalin.http.Handler
@@ -52,17 +59,32 @@ object AnnotatedRouting : RoutingApiInitializer<AnnotatedRoutingConfig> {
         setup.invokeAsSamWithReceiver(configuration)
 
         val loader = ReflectiveEndpointLoader(configuration.resultHandlers)
+        val registeredEventListeners = mutableMapOf<JavalinLifecycleEvent, AnnotatedEvent>()
         val registeredRoutes = mutableListOf<AnnotatedRoute>()
         val registeredExceptionHandlers = mutableListOf<AnnotatedException>()
 
         configuration.registeredRoutes.forEach {
+            val detectedEventListeners = loader.loadEventHandlers(it)
+            registeredEventListeners.putAll(detectedEventListeners)
+
             val detectedRoutes = loader.loadRoutesFromEndpoint(it)
             registeredRoutes.addAll(detectedRoutes)
 
             val detectedExceptionHandlers = loader.loadExceptionHandlers(it)
             registeredExceptionHandlers.addAll(detectedExceptionHandlers)
         }
 
+        registeredEventListeners.forEach { (key, event) ->
+            when (key) {
+                SERVER_STARTING -> cfg.events.serverStarting { event.invoke() }
+                SERVER_STARTED -> cfg.events.serverStarted { event.invoke() }
+                SERVER_START_FAILED -> cfg.events.serverStartFailed { event.invoke() }
+                SERVER_STOP_FAILED -> cfg.events.serverStopFailed { event.invoke() }
+                SERVER_STOPPING -> cfg.events.serverStopping { event.invoke() }
+                SERVER_STOPPED -> cfg.events.serverStopped { event.invoke() }
+            }
+        }
+
         registeredRoutes
             .sortRoutes()
             .groupBy { RouteIdentifier(it.method, it.path) }

diff --git a/...ated/src/main/kotlin/io/javalin/community/routing/annotations/ReflectiveEndpointLoader.kt b/...ated/src/main/kotlin/io/javalin/community/routing/annotations/ReflectiveEndpointLoader.kt
@@ -4,6 +4,7 @@ import io.javalin.community.routing.Route
 import io.javalin.community.routing.Route.BEFORE_MATCHED
 import io.javalin.community.routing.dsl.DefaultDslException
 import io.javalin.community.routing.dsl.DefaultDslRoute
+import io.javalin.event.JavalinLifecycleEvent
 import io.javalin.http.Context
 import io.javalin.http.HttpStatus
 import io.javalin.validation.Validation
@@ -14,6 +15,7 @@ import kotlin.reflect.KClass
 
 typealias AnnotatedRoute = DefaultDslRoute<Context, Unit>
 typealias AnnotatedException = DefaultDslException<Context, Exception, Unit>
+typealias AnnotatedEvent = () -> Unit
 
 internal class ReflectiveEndpointLoader(
     private val resultHandlers: Map<Class<*>, HandlerResultConsumer<*>>
@@ -122,6 +124,27 @@ internal class ReflectiveEndpointLoader(
         return dslExceptions
     }
 
+    fun loadEventHandlers(endpoint: Any): Map<JavalinLifecycleEvent, AnnotatedEvent> {
+        val endpointClass = endpoint::class.java
+        val dslEvents = mutableMapOf<JavalinLifecycleEvent, AnnotatedEvent>()
+
+        endpointClass.declaredMethods.forEach { method ->
+            val lifecycleEventHandler = method.getAnnotation<LifecycleEventHandler>() ?: return@forEach
+
+            require(method.trySetAccessible()) {
+                "Unable to access method $method in class $endpointClass"
+            }
+
+            dslEvents[lifecycleEventHandler.lifecycleEvent] =  object : AnnotatedEvent {
+                override fun invoke() {
+                    method.invoke(endpoint)
+                }
+            }
+        }
+
+        return dslEvents
+    }
+
     @Suppress("UNCHECKED_CAST")
     private fun findResultHandler(method: Method): HandlerResultConsumer<Any?> =
         resultHandlers.asSequence()

diff --git a/...-annotated/src/test/java/io/javalin/community/routing/annotations/AnnotatedRoutingTest.kt b/...-annotated/src/test/java/io/javalin/community/routing/annotations/AnnotatedRoutingTest.kt
@@ -3,6 +3,7 @@ package io.javalin.community.routing.annotations
 import io.javalin.Javalin
 import io.javalin.community.routing.Route
 import io.javalin.community.routing.annotations.AnnotatedRouting.Annotated
+import io.javalin.event.JavalinLifecycleEvent.SERVER_STARTED
 import io.javalin.http.Context
 import io.javalin.http.HandlerType
 import io.javalin.http.HttpStatus
@@ -294,6 +295,26 @@ class AnnotatedRoutingTest {
             assertThat(Unirest.get("${client.origin}/throwing").asString().body).isEqualTo("java.lang.IllegalStateException")
         }
 
+    @Test
+    fun `should handle lifecycle events`() {
+        val log = mutableListOf<String>()
+
+        JavalinTest.test(
+            Javalin.create {
+                it.router.mount(Annotated) { cfg ->
+                    cfg.registerEndpoints(object {
+                        @LifecycleEventHandler(SERVER_STARTED)
+                        fun onStart() {
+                            log.add("Started")
+                        }
+                    })
+                }
+            }
+        ) { _, _ ->
+            assertThat(log).containsExactly("Started")
+        }
+    }
+
     @Test
     fun `should throw for unsupported return types`() {
         assertThatThrownBy {