Option to register data fetchers on GraphQLCodeRegistry

Closes gh-312

Author: rstoyanchev

spring-graphql/src/main/java/org/springframework/graphql/data/method/annotation/support/AnnotatedControllerConfigurer.java

@@ -32,6 +32,7 @@
 import graphql.schema.DataFetcher;
 import graphql.schema.DataFetchingEnvironment;
 import graphql.schema.FieldCoordinates;
+import graphql.schema.GraphQLCodeRegistry;
 import graphql.schema.idl.RuntimeWiring;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
@@ -72,6 +73,10 @@
  * annotated handler methods in {@link Controller @Controller} classes and
  * registers them as {@link DataFetcher}s.
  *
+ * <p>In addition to initializing a {@link RuntimeWiring.Builder}, this class, also
+ * provides an option to {@link #configure(GraphQLCodeRegistry.Builder) configure}
+ * data fetchers on a {@link GraphQLCodeRegistry.Builder}.
+ *
  * @author Rossen Stoyanchev
  * @author Brian Clozel
  * @since 1.0.0
@@ -185,7 +190,7 @@ public void afterPropertiesSet() {
 	}
 
 	@Override
-	public void configure(RuntimeWiring.Builder builder) {
+	public void configure(RuntimeWiring.Builder runtimeWiringBuilder) {
 		Assert.state(this.argumentResolvers != null, "`argumentResolvers` is not initialized");
 
 		findHandlerMethods().forEach((info) -> {
@@ -197,7 +202,7 @@ public void configure(RuntimeWiring.Builder builder) {
 				String dataLoaderKey = registerBatchLoader(info);
 				dataFetcher = new BatchMappingDataFetcher(dataLoaderKey);
 			}
-			builder.type(info.getCoordinates().getTypeName(), typeBuilder ->
+			runtimeWiringBuilder.type(info.getCoordinates().getTypeName(), typeBuilder ->
 					typeBuilder.dataFetcher(info.getCoordinates().getFieldName(), dataFetcher));
 		});
 	}
@@ -372,6 +377,26 @@ else if (clazz.equals(Mono.class) || clazz.equals(Map.class)) {
 		return dataLoaderKey;
 	}
 
+	/**
+	 * Alternative to {@link #configure(RuntimeWiring.Builder)} that registers
+	 * data fetchers in a {@link GraphQLCodeRegistry.Builder}. This could be
+	 * used with programmatic creation of {@link graphql.schema.GraphQLSchema}.
+	 */
+	@SuppressWarnings("rawtypes")
+	public void configure(GraphQLCodeRegistry.Builder codeRegistryBuilder) {
+
+		RuntimeWiring.Builder wiringBuilder = RuntimeWiring.newRuntimeWiring();
+		configure(wiringBuilder);
+		RuntimeWiring runtimeWiring = wiringBuilder.build();
+
+		runtimeWiring.getDataFetchers().forEach((typeName, dataFetcherMap) -> {
+			dataFetcherMap.forEach((key, value) -> {
+				FieldCoordinates coordinates = FieldCoordinates.coordinates(typeName, key);
+				codeRegistryBuilder.dataFetcher(coordinates, (DataFetcher<?>) value);
+			});
+		});
+	}
+
 
 	private static class MappingInfo {