fix: Handle firing delete events twice

ExpediaGroup · Nov 2, 2023 · 46f3e77 · 46f3e77
1 parent 6647bc7
commit 46f3e77
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Showing 2 changed files with 38 additions and 1 deletion.
diff --git a/...n/java/com/expediagroup/streamplatform/streamregistry/state/DefaultEntityViewUpdater.java b/...n/java/com/expediagroup/streamplatform/streamregistry/state/DefaultEntityViewUpdater.java
@@ -90,7 +90,7 @@ private <K extends Entity.Key<S>, S extends Specification> Entity<K, S> update(S
   }
 
   private <K extends Entity.Key<S>, S extends Specification> Entity<K, S> delete(SpecificationDeletionEvent<K, S> event) {
-    val oldEntity = (Entity<K, S>) getExistingEntity(event.getKey());
+    val oldEntity = (Entity<K, S>) getPossiblyDeletedEntity(event.getKey());
     entities.put(event.getKey(), deleted(oldEntity));
     log.debug("Deleted entity for {}", event.getKey());
     return oldEntity;
@@ -108,6 +108,24 @@ private <K extends Entity.Key<S>, S extends Specification> Entity<K, S> delete(S
     return oldEntity;
   }
 
+  /**
+   * There is a chance the entity will have already been deleted.
+   */
+  private Entity<?, ?> getPossiblyDeletedEntity(Entity.Key<?> key) {
+    val stateValue = Optional.ofNullable(entities.get(key));
+    stateValue.ifPresent(it -> {
+        if (it.deleted) {
+          log.debug("Found deleted entity for key={}", key);
+        } else {
+          log.debug("Found entity for key={}", key);
+        }
+      }
+    );
+    return stateValue
+      .map(it -> it.entity)
+      .orElse(null);
+  }
+
   private Entity<?, ?> getExistingEntity(Entity.Key<?> key) {
     return Optional.ofNullable(entities.get(key))
       .filter(it -> !it.deleted)

diff --git a/...test/java/com/expediagroup/streamplatform/streamregistry/state/EntityViewUpdaterTest.java b/...test/java/com/expediagroup/streamplatform/streamregistry/state/EntityViewUpdaterTest.java
@@ -138,6 +138,25 @@ public void deleteSpecificationEvent() {
     assertThat(entities, hasEntry(key, deleted(entity.withStatus(oldStatus))));
   }
 
+  @Test
+  public void doubleDeleteSpecificationEvent() {
+    val previousEntity = underTest.update(specificationEvent);
+
+    assertThat(previousEntity, is(nullValue()));
+    assertThat(entities, is(aMapWithSize(1)));
+    assertThat(entities, hasEntry(key, existing(entity.withStatus(oldStatus))));
+
+    val deletedEntity = underTest.update(specificationDeletionEvent);
+    assertThat(deletedEntity, is(entity.withStatus(oldStatus)));
+    assertThat(entities, is(aMapWithSize(1)));
+    assertThat(entities, hasEntry(key, deleted(entity.withStatus(oldStatus))));
+
+    val doubleDeletedEntity = underTest.update(specificationDeletionEvent);
+    assertThat(doubleDeletedEntity, is(entity.withStatus(oldStatus)));
+    assertThat(entities, is(aMapWithSize(1)));
+    assertThat(entities, hasEntry(key, deleted(entity.withStatus(oldStatus))));
+  }
+
   @Test
   public void deleteStatusEvent() {
     entities.put(key, existing(oldEntity));