Improve cloud event to json conversion (#1445)

Relies on SDK serialization/deserialization.

Adds small patch to be compliant with expected behaviour

Signed-off-by: fjtirado <ftirados@ibm.com>

Author: fjtirado

impl/json-utils/src/main/java/io/serverlessworkflow/impl/jackson/JacksonCloudEventUtils.java

@@ -15,14 +15,13 @@
  */
 package io.serverlessworkflow.impl.jackson;
 
-import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.databind.JsonNode;
 import com.fasterxml.jackson.databind.node.NullNode;
+import com.fasterxml.jackson.databind.node.ObjectNode;
+import com.fasterxml.jackson.databind.node.POJONode;
 import io.cloudevents.CloudEvent;
 import io.cloudevents.CloudEventData;
-import io.cloudevents.core.provider.EventFormatProvider;
 import io.cloudevents.jackson.JsonCloudEventData;
-import io.cloudevents.jackson.JsonFormat;
 import java.io.IOException;
 import java.io.UncheckedIOException;
 import java.time.OffsetDateTime;
@@ -35,14 +34,11 @@ public static JsonNode toJsonNode(CloudEvent event) {
     if (event == null) {
       return NullNode.instance;
     }
-    // Delegate entirely to the official CloudEvents SDK
-    byte[] serialized =
-        EventFormatProvider.getInstance().resolveFormat(JsonFormat.CONTENT_TYPE).serialize(event);
-    try {
-      return JsonUtils.mapper().readTree(serialized);
-    } catch (IOException e) {
-      throw new UncheckedIOException(e);
+    ObjectNode node = JsonUtils.mapper().convertValue(event, ObjectNode.class);
+    if (node.get("data") instanceof POJONode) {
+      node.set("data", toJsonNode(event.getData()));
     }
+    return node;
   }
 
   public static OffsetDateTime toOffset(Date date) {
@@ -66,14 +62,7 @@ public static CloudEvent toCloudEvent(JsonNode node) {
     if (node == null || node.isNull()) {
       return null;
     }
-    try {
-      byte[] ceBytes = JsonUtils.mapper().writeValueAsBytes(node);
-      return EventFormatProvider.getInstance()
-          .resolveFormat(JsonFormat.CONTENT_TYPE)
-          .deserialize(ceBytes);
-    } catch (JsonProcessingException e) {
-      throw new IllegalArgumentException("Failed to deserialize JsonNode to CloudEvent", e);
-    }
+    return JsonUtils.mapper().convertValue(node, CloudEvent.class);
   }
 
   public static CloudEventData toCloudEventData(JsonNode node) {

impl/json-utils/src/test/java/io/serverlessworkflow/impl/jackson/JacksonCloudEventUtilsTest.java

@@ -25,21 +25,44 @@
 import io.cloudevents.CloudEventData;
 import io.cloudevents.core.builder.CloudEventBuilder;
 import io.cloudevents.core.data.BytesCloudEventData;
+import io.cloudevents.jackson.JsonCloudEventData;
 import java.net.URI;
 import java.nio.charset.StandardCharsets;
 import org.junit.jupiter.api.Test;
 
 public class JacksonCloudEventUtilsTest {
 
   private CloudEvent createSampleEvent() {
+    return createEventBuilder()
+        .withData("{\"status\":\"NEEDS_REVISION\"}".getBytes(StandardCharsets.UTF_8))
+        .build();
+  }
+
+  private CloudEventBuilder createEventBuilder() {
     return CloudEventBuilder.v1()
         .withId("5dc4698e-5f98-470e-bb76-04218fe2dd0f")
         .withSource(URI.create("api:/newsletter"))
         .withType("org.acme.newsletter.review.done")
         .withDataContentType("application/json")
-        .withExtension("flowinstanceid", "01KMRBFA19GZYW3XY895Z4SNCK")
-        .withData("{\"status\":\"NEEDS_REVISION\"}".getBytes(StandardCharsets.UTF_8))
-        .build();
+        .withExtension("flowinstanceid", "01KMRBFA19GZYW3XY895Z4SNCK");
+  }
+
+  @Test
+  public void testCloudEventSerializationNullData() {
+    CloudEvent event = createEventBuilder().build();
+
+    JsonNode node = JacksonCloudEventUtils.toJsonNode(event);
+
+    assertNotNull(node);
+    assertTrue(node.has("specversion"), "Missing mandatory specversion attribute");
+    assertEquals("1.0", node.get("specversion").asText());
+
+    assertFalse(node.has("specVersion"), "Jackson POJO serializer mangled the envelope!");
+
+    assertEquals("5dc4698e-5f98-470e-bb76-04218fe2dd0f", node.get("id").asText());
+    assertEquals("01KMRBFA19GZYW3XY895Z4SNCK", node.get("flowinstanceid").asText());
+
+    assertFalse(node.has("data"));
   }
 
   @Test
@@ -61,6 +84,30 @@ public void testCloudEventSerialization() {
     assertEquals("NEEDS_REVISION", node.get("data").get("status").asText());
   }
 
+  @Test
+  public void testCloudEventSerializationJson() {
+    CloudEvent event =
+        createEventBuilder()
+            .withData(
+                JsonCloudEventData.wrap(
+                    JsonUtils.mapper().createObjectNode().put("status", "NEEDS_REVISION")))
+            .build();
+
+    JsonNode node = JacksonCloudEventUtils.toJsonNode(event);
+
+    assertNotNull(node);
+    assertTrue(node.has("specversion"), "Missing mandatory specversion attribute");
+    assertEquals("1.0", node.get("specversion").asText());
+
+    assertFalse(node.has("specVersion"), "Jackson POJO serializer mangled the envelope!");
+
+    assertEquals("5dc4698e-5f98-470e-bb76-04218fe2dd0f", node.get("id").asText());
+    assertEquals("01KMRBFA19GZYW3XY895Z4SNCK", node.get("flowinstanceid").asText());
+
+    assertTrue(node.has("data"));
+    assertEquals("NEEDS_REVISION", node.get("data").get("status").asText());
+  }
+
   @Test
   public void testCloudEventDeserialization() {
     CloudEvent originalEvent = createSampleEvent();