Allows to set a custom Relay implementation, in order to add fields in the auto generated types

Author: Thomas Draier

src/main/java/graphql/annotations/GraphQLAnnotations.java

@@ -80,12 +80,11 @@
 @Component
 public class GraphQLAnnotations implements GraphQLAnnotationsProcessor {
 
-    private static final Relay RELAY_TYPES = new Relay();
-
     private static final List<Class> TYPES_FOR_CONNECTION = Arrays.asList(GraphQLObjectType.class, GraphQLInterfaceType.class, GraphQLUnionType.class, GraphQLTypeReference.class);
 
     private Map<String, graphql.schema.GraphQLType> typeRegistry = new HashMap<>();
     private final Stack<String> processing = new Stack<>();
+    private Relay relay = new Relay();
 
     public GraphQLAnnotations() {
         this(new DefaultTypeFunction());
@@ -102,6 +101,10 @@ public static GraphQLAnnotations getInstance() {
         return instance;
     }
 
+    public void setRelay(Relay relay) {
+        this.relay = relay;
+    }
+
     @Override
     public graphql.schema.GraphQLType getInterface(Class<?> iface) throws GraphQLAnnotationsException {
         String typeName = getTypeName(iface);
@@ -502,9 +505,9 @@ private GraphQLOutputType getGraphQLConnection(boolean isConnection, AccessibleO
                 assert wrappedType instanceof GraphQLObjectType;
                 String annValue = field.getAnnotation(GraphQLConnection.class).name();
                 String connectionName = annValue.isEmpty() ? wrappedType.getName() : annValue;
-                GraphQLObjectType edgeType = RELAY_TYPES.edgeType(connectionName, (GraphQLOutputType) wrappedType, null, Collections.<GraphQLFieldDefinition>emptyList());
-                outputType = RELAY_TYPES.connectionType(connectionName, edgeType, Collections.emptyList());
-                builder.argument(RELAY_TYPES.getConnectionFieldArguments());
+                GraphQLObjectType edgeType = relay.edgeType(connectionName, (GraphQLOutputType) wrappedType, null, Collections.<GraphQLFieldDefinition>emptyList());
+                outputType = relay.connectionType(connectionName, edgeType, Collections.emptyList());
+                builder.argument(relay.getConnectionFieldArguments());
             }
         }
         return outputType;
@@ -571,7 +574,7 @@ protected GraphQLFieldDefinition getField(Method method) throws GraphQLAnnotatio
             List<GraphQLFieldDefinition> fieldDefinitions = outputType instanceof GraphQLObjectType ?
                     ((GraphQLObjectType) outputType).getFieldDefinitions() :
                     ((GraphQLInterfaceType) outputType).getFieldDefinitions();
-            relay = RELAY_TYPES.mutationWithClientMutationId(title, method.getName(),
+            relay = GraphQLAnnotations.this.relay.mutationWithClientMutationId(title, method.getName(),
                     args.stream().
                             map(t -> newInputObjectField().name(t.getName()).type(t.getType()).description(t.getDescription()).build()).
                             collect(Collectors.toList()), fieldDefinitions, null);

src/test/java/graphql/annotations/GraphQLConnectionTest.java

@@ -16,7 +16,10 @@
 
 import graphql.ExecutionResult;
 import graphql.GraphQL;
+import graphql.annotations.util.CustomRelay;
+import graphql.relay.Relay;
 import graphql.schema.DataFetchingEnvironment;
+import graphql.schema.GraphQLList;
 import graphql.schema.GraphQLObjectType;
 import graphql.schema.GraphQLSchema;
 import org.testng.annotations.Test;
@@ -113,6 +116,25 @@ public void methodList() {
 
     }
 
+    @Test
+    public void customRelayMethodList() {
+        try {
+            GraphQLAnnotations.getInstance().setRelay(new CustomRelay());
+            GraphQLObjectType object = GraphQLAnnotations.object(TestConnections.class);
+            GraphQLSchema schema = newSchema().query(object).build();
+
+            graphql.schema.GraphQLObjectType f = (GraphQLObjectType) schema.getType("ObjConnection");
+            assertTrue(f.getFieldDefinitions().size() == 4);
+            assertTrue(f.getFieldDefinition("nodes").getType() instanceof GraphQLList);
+            assertEquals(((GraphQLList)f.getFieldDefinition("nodes").getType()).getWrappedType().getName(), "Obj");
+
+            GraphQLObjectType pageInfo = (GraphQLObjectType) schema.getType("PageInfo");
+            assertTrue(pageInfo.getFieldDefinition("additionalInfo") != null);
+        } finally {
+            GraphQLAnnotations.getInstance().setRelay(new Relay());
+        }
+    }
+
     public void testResult(String name, ExecutionResult result) {
         Map<String, Map<String, List<Map<String, Map<String, Object>>>>> data = result.getData();
         List<Map<String, Map<String, Object>>> edges = data.get(name).get("edges");

src/test/java/graphql/annotations/util/CustomRelay.java

@@ -0,0 +1,77 @@
+/**
+ * Copyright 2016 Yurii Rashkovskii
+ *
+ * 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
+ */
+package graphql.annotations.util;
+
+import graphql.relay.Relay;
+import graphql.schema.*;
+
+import java.util.List;
+
+import static graphql.Scalars.GraphQLBoolean;
+import static graphql.Scalars.GraphQLInt;
+import static graphql.Scalars.GraphQLString;
+import static graphql.schema.GraphQLFieldDefinition.newFieldDefinition;
+import static graphql.schema.GraphQLObjectType.newObject;
+
+public class CustomRelay extends Relay {
+
+    private GraphQLObjectType pageInfoType = newObject()
+            .name("PageInfo")
+            .description("Information about pagination in a connection.")
+            .field(newFieldDefinition()
+                    .name("hasNextPage")
+                    .type(new GraphQLNonNull(GraphQLBoolean))
+                    .description("When paginating forwards, are there more items?"))
+            .field(newFieldDefinition()
+                    .name("hasPreviousPage")
+                    .type(new GraphQLNonNull(GraphQLBoolean))
+                    .description("When paginating backwards, are there more items?"))
+            .field(newFieldDefinition()
+                    .name("startCursor")
+                    .type(GraphQLString)
+                    .description("When paginating backwards, the cursor to continue."))
+            .field(newFieldDefinition()
+                    .name("endCursor")
+                    .type(GraphQLString)
+                    .description("When paginating forwards, the cursor to continue."))
+            .field(newFieldDefinition()
+                    .name("additionalInfo")
+                    .type(GraphQLString))
+            .build();
+
+    @Override
+    public GraphQLObjectType connectionType(String name, GraphQLObjectType edgeType, List<GraphQLFieldDefinition> connectionFields) {
+        return newObject()
+                .name(name + "Connection")
+                .description("A connection to a list of items.")
+                .field(newFieldDefinition()
+                        .name("edges")
+                        .description("a list of edges")
+                        .type(new GraphQLList(edgeType)))
+                .field(newFieldDefinition()
+                        .name("nodes")
+                        .description("a list of nodes")
+                        .type(new GraphQLList(edgeType.getFieldDefinition("node").getType())))
+                .field(newFieldDefinition()
+                        .name("pageInfo")
+                        .description("details about this specific page")
+                        .type(new GraphQLNonNull(pageInfoType)))
+                .field(newFieldDefinition()
+                        .name("totalCount")
+                        .description("number of nodes in connection")
+                        .type(GraphQLInt))
+                .fields(connectionFields)
+                .build();
+    }}