Added test for subscription source field (batch)

server/integration-tests/src/test/java/io/smallrye/graphql/tests/subscription/SubscriptionFieldBatchingTest.java

@@ -0,0 +1,121 @@
+package io.smallrye.graphql.tests.subscription;
+
+import static org.assertj.core.api.AssertionsForClassTypes.assertThat;
+
+import java.net.URL;
+import java.util.List;
+import java.util.stream.Collectors;
+
+import jakarta.json.Json;
+import jakarta.json.JsonObject;
+
+import org.eclipse.microprofile.graphql.GraphQLApi;
+import org.eclipse.microprofile.graphql.Source;
+import org.jboss.arquillian.container.test.api.Deployment;
+import org.jboss.arquillian.junit.Arquillian;
+import org.jboss.arquillian.test.api.ArquillianResource;
+import org.jboss.shrinkwrap.api.ShrinkWrap;
+import org.jboss.shrinkwrap.api.spec.WebArchive;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+import io.smallrye.graphql.api.Subscription;
+import io.smallrye.graphql.client.Response;
+import io.smallrye.graphql.client.dynamic.api.DynamicGraphQLClient;
+import io.smallrye.graphql.client.vertx.dynamic.VertxDynamicGraphQLClientBuilder;
+import io.smallrye.mutiny.Multi;
+
+@RunWith(Arquillian.class)
+public class SubscriptionFieldBatchingTest {
+    @Deployment
+    public static WebArchive deployment() {
+        return ShrinkWrap.create(WebArchive.class, "subscription-field-batching-test.war")
+                .addClasses(Bar.class, MyApi.class);
+    }
+
+    @ArquillianResource
+    URL testingURL;
+
+    @GraphQLApi
+    public static class MyApi {
+
+        public List<Integer> sourceBatchField(@Source List<Bar> bars) {
+            if (bars.size() != 1) {
+                throw new IllegalStateException("Expected a batch size of 1");
+            }
+            return bars
+                    .stream()
+                    .map(Bar::getField1)
+                    // 111 -> 1, 222 -> 2, 333 -> 3
+                    .map(field1 -> Integer.divideUnsigned(field1, 100))
+                    .collect(Collectors.toList());
+        }
+
+        @Subscription
+        public Multi<Bar> subscriptionOperation() {
+            return Multi.createFrom().items(new Bar(111, "bar1"), new Bar(222, "bar2"), new Bar(333, "bar3"));
+        }
+    }
+
+    public static class Bar {
+        private int field1;
+        private String field2;
+
+        public Bar() {
+        }
+
+        public Bar(int field1, String field2) {
+            this.field1 = field1;
+            this.field2 = field2;
+        }
+
+        public int getField1() {
+            return field1;
+        }
+
+        public void setField1(int field1) {
+            this.field1 = field1;
+        }
+
+        public String getField2() {
+            return field2;
+        }
+
+        public void setField2(String field2) {
+            this.field2 = field2;
+        }
+    }
+
+    @Test
+    public void subscriptionFieldBatchingTest() throws Exception {
+        try (DynamicGraphQLClient dynamicGraphQLClient = new VertxDynamicGraphQLClientBuilder()
+                .url(testingURL.toString() + "graphql")
+                .build()) {
+            List<Response> responses = dynamicGraphQLClient
+                    .subscription(
+                            "subscription subscriptionOperation { subscriptionOperation { field1 field2 sourceBatchField } }")
+                    .subscribe()
+                    .asStream()
+                    .collect(Collectors.toList());
+
+            assertThat(responses.size()).isEqualTo(3);
+            for (int i = 0; i < responses.size(); i++) {
+                Response response = responses.get(i);
+                assertThat(response.getData())
+                        .isNotNull();
+                assertThat(response.getErrors()).isNull();
+
+                JsonObject content = response.getData().get("subscriptionOperation").asJsonObject();
+                assertThat(content).isNotNull();
+
+                assertThat(content.containsKey("field1")).isTrue();
+                assertThat(content.containsKey("field2")).isTrue();
+                assertThat(content.containsKey("sourceBatchField")).isTrue();
+
+                assertThat(content.get("field1")).isEqualTo(Json.createValue(111 * (i + 1)));
+                assertThat(content.get("field2")).isEqualTo(Json.createValue("bar" + (i + 1)));
+                assertThat(content.get("sourceBatchField")).isEqualTo(Json.createValue(i + 1));
+            }
+        }
+    }
+}