Support custom HandlerMethodArgumentResolver

See gh-295

Author: dugenkui03

spring-graphql/src/main/java/org/springframework/graphql/data/method/HandlerMethodArgumentResolverComposite.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2021 the original author or authors.
+ * Copyright 2002-2022 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -32,6 +32,7 @@
  * Previously resolved method parameters are cached for faster lookups.
  *
  * @author Rossen Stoyanchev
+ * @author Genkui Du
  * @since 1.0.0
  */
 public class HandlerMethodArgumentResolverComposite implements HandlerMethodArgumentResolver {
@@ -49,6 +50,18 @@ public void addResolver(HandlerMethodArgumentResolver resolver) {
 		this.argumentResolvers.add(resolver);
 	}
 
+	/**
+	 * Add the given {@link HandlerMethodArgumentResolver HandlerMethodArgumentResolvers}.
+	 */
+	public HandlerMethodArgumentResolverComposite addResolvers(
+			@Nullable List<? extends HandlerMethodArgumentResolver> resolvers) {
+
+		if (resolvers != null) {
+			this.argumentResolvers.addAll(resolvers);
+		}
+		return this;
+	}
+
 	/**
 	 * Return a read-only list with the contained resolvers, or an empty list.
 	 */

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

@@ -18,11 +18,13 @@
 import java.lang.annotation.Annotation;
 import java.lang.reflect.Method;
 import java.lang.reflect.Type;
+import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.LinkedHashSet;
+import java.util.List;
 import java.util.Map;
 import java.util.Set;
 import java.util.stream.Collectors;
@@ -74,6 +76,7 @@
  *
  * @author Rossen Stoyanchev
  * @author Brian Clozel
+ * @author Genkui Du
  * @since 1.0.0
  */
 public class AnnotatedControllerConfigurer
@@ -108,6 +111,9 @@ public class AnnotatedControllerConfigurer
 	@Nullable
 	private ApplicationContext applicationContext;
 
+	@Nullable
+	private List<HandlerMethodArgumentResolver> customArgumentResolvers;
+
 	@Nullable
 	private HandlerMethodArgumentResolverComposite argumentResolvers;
 
@@ -143,6 +149,22 @@ public void setApplicationContext(ApplicationContext applicationContext) {
 		this.applicationContext = applicationContext;
 	}
 
+	/**
+	 * Provide resolvers for custom argument types. Custom resolvers are ordered
+	 * after built-in ones.
+	 */
+	public void setCustomArgumentResolvers(@Nullable List<HandlerMethodArgumentResolver> argumentResolvers) {
+		this.customArgumentResolvers = argumentResolvers;
+	}
+
+	/**
+	 * Return the custom argument resolvers, or {@code null}.
+	 */
+	@Nullable
+	public List<HandlerMethodArgumentResolver> getCustomArgumentResolvers() {
+		return this.customArgumentResolvers;
+	}
+
 	protected final ApplicationContext obtainApplicationContext() {
 		Assert.state(this.applicationContext != null, "No ApplicationContext");
 		return this.applicationContext;
@@ -151,37 +173,58 @@ protected final ApplicationContext obtainApplicationContext() {
 
 	@Override
 	public void afterPropertiesSet() {
-		this.argumentResolvers = new HandlerMethodArgumentResolverComposite();
+		List<HandlerMethodArgumentResolver> resolvers = getDefaultArgumentResolvers();
+		this.argumentResolvers = new HandlerMethodArgumentResolverComposite().addResolvers(resolvers);
+
+		if (beanValidationPresent) {
+			this.validator = HandlerMethodInputValidatorFactory.create(obtainApplicationContext());
+		}
+
+		if (beanValidationPresent) {
+			this.validator = HandlerMethodInputValidatorFactory.create(obtainApplicationContext());
+		}
+	}
+
+	/**
+	 * Return the list of argument resolvers to use including built-in resolvers
+	 * and custom resolvers provided via {@link #setCustomArgumentResolvers}.
+	 */
+	private List<HandlerMethodArgumentResolver> getDefaultArgumentResolvers() {
+		List<HandlerMethodArgumentResolver> resolvers = new ArrayList<>();
+
 
 		// Annotation based
 		if (springDataPresent) {
 			// Must be ahead of ArgumentMethodArgumentResolver
-			this.argumentResolvers.addResolver(new ProjectedPayloadMethodArgumentResolver());
+			resolvers.add(new ProjectedPayloadMethodArgumentResolver());
 		}
-		this.argumentResolvers.addResolver(new ArgumentMapMethodArgumentResolver());
+		resolvers.add(new ArgumentMapMethodArgumentResolver());
 		GraphQlArgumentInitializer initializer = new GraphQlArgumentInitializer(this.conversionService);
-		this.argumentResolvers.addResolver(new ArgumentMethodArgumentResolver(initializer));
-		this.argumentResolvers.addResolver(new ArgumentsMethodArgumentResolver(initializer));
-		this.argumentResolvers.addResolver(new ContextValueMethodArgumentResolver());
+		resolvers.add(new ArgumentMethodArgumentResolver(initializer));
+		resolvers.add(new ArgumentsMethodArgumentResolver(initializer));
+		resolvers.add(new ContextValueMethodArgumentResolver());
 
 		// Type based
-		this.argumentResolvers.addResolver(new DataFetchingEnvironmentMethodArgumentResolver());
-		this.argumentResolvers.addResolver(new DataLoaderMethodArgumentResolver());
+		resolvers.add(new DataFetchingEnvironmentMethodArgumentResolver());
+		resolvers.add(new DataLoaderMethodArgumentResolver());
 		if (springSecurityPresent) {
-			this.argumentResolvers.addResolver(new PrincipalMethodArgumentResolver());
+			resolvers.add(new PrincipalMethodArgumentResolver());
 			BeanResolver beanResolver = new BeanFactoryResolver(obtainApplicationContext());
-			this.argumentResolvers.addResolver(new AuthenticationPrincipalArgumentResolver(beanResolver));
+			resolvers.add(new AuthenticationPrincipalArgumentResolver(beanResolver));
 		}
 		if (KotlinDetector.isKotlinPresent()) {
-			this.argumentResolvers.addResolver(new ContinuationHandlerMethodArgumentResolver());
+			resolvers.add(new ContinuationHandlerMethodArgumentResolver());
 		}
 
-		// This works as a fallback, after other resolvers
-		this.argumentResolvers.addResolver(new SourceMethodArgumentResolver());
+		// This works as a fallback, after other resolvers, but before custom resolvers
+		resolvers.add(new SourceMethodArgumentResolver());
 
-		if (beanValidationPresent) {
-			this.validator = HandlerMethodInputValidatorFactory.create(obtainApplicationContext());
+		// Custom argument resolvers
+		if (getCustomArgumentResolvers() != null) {
+			resolvers.addAll(getCustomArgumentResolvers());
 		}
+
+		return resolvers;
 	}
 
 	@Override

spring-graphql/src/test/java/org/springframework/graphql/data/method/annotation/support/SchemaMappingInvocationTests.java

@@ -15,6 +15,12 @@
  */
 package org.springframework.graphql.data.method.annotation.support;
 
+import java.lang.annotation.Documented;
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+import java.util.Collections;
 import java.util.List;
 import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.atomic.AtomicReference;
@@ -23,6 +29,9 @@
 import graphql.schema.DataFetchingEnvironment;
 import org.dataloader.DataLoader;
 import org.junit.jupiter.api.Test;
+import org.springframework.core.MethodParameter;
+import org.springframework.graphql.data.method.HandlerMethodArgumentResolver;
+import org.springframework.util.Assert;
 import reactor.core.publisher.Flux;
 import reactor.core.publisher.Mono;
 import reactor.test.StepVerifier;
@@ -54,6 +63,7 @@
  *
  * @author Rossen Stoyanchev
  * @author Mark Paluch
+ * @author Genkui Du
  */
 public class SchemaMappingInvocationTests {
 
@@ -215,7 +225,7 @@ private GraphQlService graphQlService() {
 		context.refresh();
 
 		return GraphQlSetup.schemaResource(BookSource.schema)
-				.runtimeWiringForAnnotatedControllers(context)
+				.runtimeWiringForAnnotatedControllers(context, Collections.singletonList(new DefaultValueArgumentResolver()))
 				.dataLoaders(registry)
 				.toGraphQlService();
 	}
@@ -231,7 +241,8 @@ public BookController(BatchLoaderRegistry batchLoaderRegistry) {
 		}
 
 		@QueryMapping
-		public Book bookById(@Argument Long id) {
+		public Book bookById(@Argument Long id, @DefaultValueAnnotation(value = 1) long defaultValue) {
+			Assert.isTrue(defaultValue == 1,"custom HandlerMethodArgumentResolver error.");
 			return BookSource.getBookWithoutAuthor(id);
 		}
 
@@ -280,4 +291,27 @@ interface BookProjection {
 
 	}
 
+	private static class DefaultValueArgumentResolver implements HandlerMethodArgumentResolver {
+		@Override
+		public boolean supportsParameter(MethodParameter parameter) {
+			return parameter.hasParameterAnnotation(DefaultValueAnnotation.class);
+		}
+
+		@Override
+		public Object resolveArgument(MethodParameter parameter, DataFetchingEnvironment environment) {
+			DefaultValueAnnotation annotation = parameter.getParameterAnnotation(DefaultValueAnnotation.class);
+			Assert.state(annotation != null, "Expected @CustomArgumentResolverAnnotation annotation");
+			return annotation.value();
+		}
+	}
+
+	@Target(ElementType.PARAMETER)
+	@Retention(RetentionPolicy.RUNTIME)
+	@Documented
+	private @interface DefaultValueAnnotation {
+
+		long value() default 0;
+
+	}
+
 }

spring-graphql/src/testFixtures/java/org/springframework/graphql/GraphQlSetup.java

@@ -28,6 +28,7 @@
 import org.springframework.context.ApplicationContext;
 import org.springframework.core.io.ByteArrayResource;
 import org.springframework.core.io.Resource;
+import org.springframework.graphql.data.method.HandlerMethodArgumentResolver;
 import org.springframework.graphql.data.method.annotation.support.AnnotatedControllerConfigurer;
 import org.springframework.graphql.execution.DataFetcherExceptionResolver;
 import org.springframework.graphql.execution.DataLoaderRegistrar;
@@ -85,8 +86,13 @@ public GraphQlSetup runtimeWiring(RuntimeWiringConfigurer configurer) {
 	}
 
 	public GraphQlSetup runtimeWiringForAnnotatedControllers(ApplicationContext context) {
+		return this.runtimeWiringForAnnotatedControllers(context, new ArrayList<>());
+	}
+
+	public GraphQlSetup runtimeWiringForAnnotatedControllers(ApplicationContext context, List<HandlerMethodArgumentResolver> argumentResolverList) {
 		AnnotatedControllerConfigurer configurer = new AnnotatedControllerConfigurer();
 		configurer.setApplicationContext(context);
+		configurer.setCustomArgumentResolvers(argumentResolverList);
 		configurer.afterPropertiesSet();
 		return runtimeWiring(configurer);
 	}