Clean up the GrpcBackedQueryUpdateMessage

-Rename payload to serializedPayload to be in line with the other gRPC
backed messages
-Change GrpcMetaData metaData to Supplier<MetaData>to be in line with
the other gRPC backed messages
-Provide private constructor to allow usage of withMetaData
-Implement withMetaData and andMetaData
-Provide test for the GrpcBackedQueryUpdateMessage

axon-server-connector/src/main/java/org/axonframework/axonserver/connector/query/subscription/GrpcBackedQueryUpdateMessage.java

@@ -5,7 +5,7 @@
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *     http://www.apache.org/licenses/LICENSE-2.0
+ *    http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -25,6 +25,7 @@
 import org.axonframework.serialization.Serializer;
 
 import java.util.Map;
+import java.util.function.Supplier;
 
 /**
  * Wrapper that allows clients to access a gRPC {@link QueryUpdate} as a {@link SubscriptionQueryUpdateMessage}.
@@ -36,8 +37,8 @@
 class GrpcBackedQueryUpdateMessage<U> implements SubscriptionQueryUpdateMessage<U> {
 
     private final QueryUpdate queryUpdate;
-    private final LazyDeserializingObject<U> payload;
-    private final GrpcMetaData metadata;
+    private final LazyDeserializingObject<U> serializedPayload;
+    private final Supplier<MetaData> metaDataSupplier;
 
     /**
      * Instantiate a {@link GrpcBackedQueryUpdateMessage} with the given {@code queryUpdate}, using the provided
@@ -49,8 +50,17 @@ class GrpcBackedQueryUpdateMessage<U> implements SubscriptionQueryUpdateMessage<
      */
     public GrpcBackedQueryUpdateMessage(QueryUpdate queryUpdate, Serializer serializer) {
         this.queryUpdate = queryUpdate;
-        this.payload = new LazyDeserializingObject<>(new GrpcSerializedObject(queryUpdate.getPayload()), serializer);
-        this.metadata = new GrpcMetaData(queryUpdate.getMetaDataMap(), serializer);
+        this.serializedPayload =
+                new LazyDeserializingObject<>(new GrpcSerializedObject(queryUpdate.getPayload()), serializer);
+        this.metaDataSupplier = new GrpcMetaData(queryUpdate.getMetaDataMap(), serializer);
+    }
+
+    private GrpcBackedQueryUpdateMessage(QueryUpdate queryUpdate,
+                                         LazyDeserializingObject<U> serializedPayload,
+                                         Supplier<MetaData> metaDataSupplier) {
+        this.queryUpdate = queryUpdate;
+        this.serializedPayload = serializedPayload;
+        this.metaDataSupplier = metaDataSupplier;
     }
 
     @Override
@@ -60,26 +70,26 @@ public String getIdentifier() {
 
     @Override
     public MetaData getMetaData() {
-        return metadata.get();
+        return metaDataSupplier.get();
     }
 
     @Override
     public U getPayload() {
-        return payload.getObject();
+        return serializedPayload.getObject();
     }
 
     @Override
     public Class<U> getPayloadType() {
-        return payload.getType();
+        return serializedPayload.getType();
     }
 
     @Override
-    public SubscriptionQueryUpdateMessage<U> withMetaData(Map<String, ?> metaData) {
-        throw new UnsupportedOperationException();
+    public GrpcBackedQueryUpdateMessage<U> withMetaData(Map<String, ?> metaData) {
+        return new GrpcBackedQueryUpdateMessage<>(queryUpdate, serializedPayload, () -> MetaData.from(metaData));
     }
 
     @Override
-    public SubscriptionQueryUpdateMessage<U> andMetaData(Map<String, ?> metaData) {
-        throw new UnsupportedOperationException();
+    public GrpcBackedQueryUpdateMessage<U> andMetaData(Map<String, ?> metaData) {
+        return withMetaData(getMetaData().mergedWith(metaData));
     }
 }

axon-server-connector/src/test/java/org/axonframework/axonserver/connector/query/subscription/GrpcBackedQueryUpdateMessageTest.java

@@ -0,0 +1,178 @@
+/*
+ * Copyright (c) 2010-2019. Axon Framework
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.axonframework.axonserver.connector.query.subscription;
+
+import io.axoniq.axonserver.grpc.query.QueryUpdate;
+import org.axonframework.axonserver.connector.AxonServerConfiguration;
+import org.axonframework.messaging.MetaData;
+import org.axonframework.queryhandling.GenericSubscriptionQueryUpdateMessage;
+import org.axonframework.queryhandling.SubscriptionQueryUpdateMessage;
+import org.axonframework.serialization.Serializer;
+import org.axonframework.serialization.xml.XStreamSerializer;
+import org.junit.*;
+
+import java.util.Objects;
+
+import static org.junit.Assert.*;
+
+public class GrpcBackedQueryUpdateMessageTest {
+
+    private static final TestQueryUpdate TEST_QUERY_UPDATE = new TestQueryUpdate("aggregateId", 42);
+    private static final String SUBSCRIPTION_ID = "subscription-id";
+
+    private final Serializer serializer = XStreamSerializer.defaultSerializer();
+    private final SubscriptionMessageSerializer subscriptionMessageSerializer =
+            new SubscriptionMessageSerializer(serializer, serializer, new AxonServerConfiguration());
+
+    @Test
+    public void testGetIdentifierReturnsTheSameIdentifierAsSpecifiedInTheQueryUpdate() {
+        SubscriptionQueryUpdateMessage<Object> testSubscriptionQueryUpdateMessage =
+                GenericSubscriptionQueryUpdateMessage.asUpdateMessage(TEST_QUERY_UPDATE);
+        QueryUpdate testQueryUpdate =
+                subscriptionMessageSerializer.serialize(testSubscriptionQueryUpdateMessage, SUBSCRIPTION_ID)
+                                             .getSubscriptionQueryResponse()
+                                             .getUpdate();
+        GrpcBackedQueryUpdateMessage<TestQueryUpdate> testSubject =
+                new GrpcBackedQueryUpdateMessage<>(testQueryUpdate, serializer);
+
+        assertEquals(testQueryUpdate.getMessageIdentifier(), testSubject.getIdentifier());
+    }
+
+    @Test
+    public void testGetMetaDataReturnsTheSameMapAsWasInsertedInTheQueryUpdate() {
+        MetaData expectedMetaData = MetaData.with("some-key", "some-value");
+        SubscriptionQueryUpdateMessage<Object> testSubscriptionQueryUpdateMessage =
+                GenericSubscriptionQueryUpdateMessage.asUpdateMessage(TEST_QUERY_UPDATE).withMetaData(expectedMetaData);
+        QueryUpdate testQueryUpdate =
+                subscriptionMessageSerializer.serialize(testSubscriptionQueryUpdateMessage, SUBSCRIPTION_ID)
+                                             .getSubscriptionQueryResponse()
+                                             .getUpdate();
+        GrpcBackedQueryUpdateMessage<TestQueryUpdate> testSubject =
+                new GrpcBackedQueryUpdateMessage<>(testQueryUpdate, serializer);
+
+        assertEquals(expectedMetaData, testSubject.getMetaData());
+    }
+
+    @Test
+    public void testGetPayloadReturnsAnIdenticalObjectAsInsertedThroughTheQueryUpdate() {
+        TestQueryUpdate expectedQueryUpdate = TEST_QUERY_UPDATE;
+        SubscriptionQueryUpdateMessage<Object> testSubscriptionQueryUpdateMessage =
+                GenericSubscriptionQueryUpdateMessage.asUpdateMessage(expectedQueryUpdate);
+        QueryUpdate testQueryUpdate =
+                subscriptionMessageSerializer.serialize(testSubscriptionQueryUpdateMessage, SUBSCRIPTION_ID)
+                                             .getSubscriptionQueryResponse()
+                                             .getUpdate();
+        GrpcBackedQueryUpdateMessage<TestQueryUpdate> testSubject =
+                new GrpcBackedQueryUpdateMessage<>(testQueryUpdate, serializer);
+
+        assertEquals(expectedQueryUpdate, testSubject.getPayload());
+    }
+
+    @Test
+    public void testGetPayloadTypeReturnsTheTypeOfTheInsertedQueryUpdate() {
+        SubscriptionQueryUpdateMessage<Object> testSubscriptionQueryUpdateMessage =
+                GenericSubscriptionQueryUpdateMessage.asUpdateMessage(TEST_QUERY_UPDATE);
+        QueryUpdate testQueryUpdate =
+                subscriptionMessageSerializer.serialize(testSubscriptionQueryUpdateMessage, SUBSCRIPTION_ID)
+                                             .getSubscriptionQueryResponse()
+                                             .getUpdate();
+        GrpcBackedQueryUpdateMessage<TestQueryUpdate> testSubject =
+                new GrpcBackedQueryUpdateMessage<>(testQueryUpdate, serializer);
+
+        assertEquals(TestQueryUpdate.class, testSubject.getPayloadType());
+    }
+
+    @Test
+    public void testWithMetaDataCompletelyReplacesTheInitialMetaDataMap() {
+        MetaData testMetaData = MetaData.with("some-key", "some-value");
+        SubscriptionQueryUpdateMessage<Object> testSubscriptionQueryUpdateMessage =
+                GenericSubscriptionQueryUpdateMessage.asUpdateMessage(TEST_QUERY_UPDATE).withMetaData(testMetaData);
+        QueryUpdate testQueryUpdate =
+                subscriptionMessageSerializer.serialize(testSubscriptionQueryUpdateMessage, SUBSCRIPTION_ID)
+                                             .getSubscriptionQueryResponse()
+                                             .getUpdate();
+        GrpcBackedQueryUpdateMessage<TestQueryUpdate> testSubject =
+                new GrpcBackedQueryUpdateMessage<>(testQueryUpdate, serializer);
+
+        MetaData replacementMetaData = MetaData.with("some-other-key", "some-other-value");
+
+        testSubject = testSubject.withMetaData(replacementMetaData);
+        MetaData resultMetaData = testSubject.getMetaData();
+        assertFalse(resultMetaData.containsKey(testMetaData.keySet().iterator().next()));
+        assertEquals(replacementMetaData, resultMetaData);
+    }
+
+    @Test
+    public void testAndMetaDataAppendsToTheExistingMetaData() {
+        MetaData testMetaData = MetaData.with("some-key", "some-value");
+        SubscriptionQueryUpdateMessage<Object> testSubscriptionQueryUpdateMessage =
+                GenericSubscriptionQueryUpdateMessage.asUpdateMessage(TEST_QUERY_UPDATE).withMetaData(testMetaData);
+        QueryUpdate testQueryUpdate =
+                subscriptionMessageSerializer.serialize(testSubscriptionQueryUpdateMessage, SUBSCRIPTION_ID)
+                                             .getSubscriptionQueryResponse()
+                                             .getUpdate();
+        GrpcBackedQueryUpdateMessage<TestQueryUpdate> testSubject =
+                new GrpcBackedQueryUpdateMessage<>(testQueryUpdate, serializer);
+
+        MetaData additionalMetaData = MetaData.with("some-other-key", "some-other-value");
+
+        testSubject = testSubject.andMetaData(additionalMetaData);
+        MetaData resultMetaData = testSubject.getMetaData();
+
+        assertTrue(resultMetaData.containsKey(testMetaData.keySet().iterator().next()));
+        assertTrue(resultMetaData.containsKey(additionalMetaData.keySet().iterator().next()));
+    }
+
+    private static class TestQueryUpdate {
+
+        private final String queryModelId;
+        private final int someFilterValue;
+
+        private TestQueryUpdate(String queryModelId, int someFilterValue) {
+            this.queryModelId = queryModelId;
+            this.someFilterValue = someFilterValue;
+        }
+
+        @SuppressWarnings("unused")
+        public String getQueryModelId() {
+            return queryModelId;
+        }
+
+        @SuppressWarnings("unused")
+        public int getSomeFilterValue() {
+            return someFilterValue;
+        }
+
+        @Override
+        public boolean equals(Object o) {
+            if (this == o) {
+                return true;
+            }
+            if (o == null || getClass() != o.getClass()) {
+                return false;
+            }
+            TestQueryUpdate that = (TestQueryUpdate) o;
+            return someFilterValue == that.someFilterValue &&
+                    Objects.equals(queryModelId, that.queryModelId);
+        }
+
+        @Override
+        public int hashCode() {
+            return Objects.hash(queryModelId, someFilterValue);
+        }
+    }
+}