Set

src/main/kotlin/no/iktdev/eventi/events/EventDispatcher.kt

@@ -8,7 +8,7 @@ import java.util.UUID
 class EventDispatcher(val eventStore: EventStore) {
 
     fun dispatch(referenceId: UUID, events: List<Event>) {
-        val derivedFromIds = events.mapNotNull { it.metadata.derivedFromId }.toSet()
+        val derivedFromIds = events.mapNotNull { it.metadata.derivedFromId }.flatten().toSet()
         val deletedEventIds = events.filterIsInstance<DeleteEvent>().map { it.deletedEventId }
         val candidates = events
             .filter { it.eventId !in derivedFromIds }

src/main/kotlin/no/iktdev/eventi/models/Event.kt

@@ -15,12 +15,12 @@ abstract class Event {
 
     fun producedFrom(task: Task): Event = self<Event>().apply {
         referenceId = task.referenceId
-        metadata = Metadata(derivedFromId = task.taskId)
+        metadata = Metadata().derivedFromEventId(task.taskId)
     }
 
-    fun derivedOf(event: Event) = self<Event>().apply {
+    fun derivedOf(vararg event: Event) = self<Event>().apply {
-        referenceId = event.referenceId
+        referenceId = event.first().referenceId
-        metadata = Metadata(derivedFromId = event.eventId)
+        metadata = Metadata().derivedFromEventId(*event.map { it.eventId }.toTypedArray())
     }
 
     fun newReferenceId() = self<Event>().apply {

src/main/kotlin/no/iktdev/eventi/models/Metadata.kt

@@ -3,7 +3,11 @@ package no.iktdev.eventi.models
 import java.time.LocalDateTime
 import java.util.UUID
 
-open class Metadata(
+class Metadata {
-    val created: LocalDateTime = LocalDateTime.now(),
+    val created: LocalDateTime = LocalDateTime.now()
-    val derivedFromId: UUID? = null
+    var derivedFromId: Set<UUID>? = null
-) {}
+        private set
+    fun derivedFromEventId(vararg id: UUID) = apply {
+        derivedFromId = id.toSet()
+    }
+}

src/main/kotlin/no/iktdev/eventi/models/Task.kt

@@ -20,7 +20,7 @@ abstract class Task {
 
     fun derivedOf(event: Event) = self<Task>().apply {
         referenceId = event.referenceId
-        metadata = Metadata(derivedFromId = event.eventId)
+        metadata = Metadata().derivedFromEventId(event.eventId)
     }
 }
 

src/test/kotlin/no/iktdev/eventi/EventDispatcherTest.kt

@@ -9,6 +9,7 @@ import no.iktdev.eventi.events.EventTypeRegistry
 import no.iktdev.eventi.models.DeleteEvent
 import no.iktdev.eventi.models.Event
 import no.iktdev.eventi.testUtil.wipe
+import org.assertj.core.api.Assertions.assertThat
 import org.junit.jupiter.api.Assertions.assertEquals
 import org.junit.jupiter.api.Assertions.assertFalse
 import org.junit.jupiter.api.Assertions.assertNotNull
@@ -52,7 +53,8 @@ class EventDispatcherTest: TestBase() {
         assertNotNull(produced)
 
         val event = produced!!.toEvent()
-        assertEquals(trigger.eventId, event!!.metadata.derivedFromId)
+        assertThat(event!!.metadata.derivedFromId).hasSize(1)
+        assertThat(event!!.metadata.derivedFromId).contains(trigger.eventId)
         assertTrue(event is DerivedEvent)
     }
 

src/test/kotlin/no/iktdev/eventi/tasks/AbstractTaskPollerTest.kt

@@ -1,11 +1,13 @@
 package no.iktdev.eventi.tasks
 
+import io.mockk.mockk
 import kotlinx.coroutines.CompletableDeferred
 import kotlinx.coroutines.ExperimentalCoroutinesApi
 import kotlinx.coroutines.test.advanceUntilIdle
 import kotlinx.coroutines.test.runTest
 import no.iktdev.eventi.InMemoryTaskStore
 import no.iktdev.eventi.TestBase
+import no.iktdev.eventi.events.EventListener
 import no.iktdev.eventi.events.EventTypeRegistry
 import no.iktdev.eventi.models.Event
 import no.iktdev.eventi.models.Task
@@ -58,8 +60,6 @@ class AbstractTaskPollerTest : TestBase() {
     open class EchoListener : TaskListener(TaskType.MIXED) {
         var result: Event? = null
 
-        override var reporter: TaskReporter? = null
-
         override fun getWorkerId() = this.javaClass.simpleName
 
         override fun supports(task: Task): Boolean {
@@ -98,7 +98,8 @@ class AbstractTaskPollerTest : TestBase() {
         advanceUntilIdle()
         val producedEvent = eventDeferred.await()
         assertThat(producedEvent).isNotNull
-        assertThat(producedEvent.metadata.derivedFromId).isEqualTo(task.taskId)
+        assertThat(producedEvent.metadata.derivedFromId).hasSize(1)
+        assertThat(producedEvent.metadata.derivedFromId).contains(task.taskId)
         assertThat((listener.result as EchoEvent).data).isEqualTo("Hello Potetmos")
     }