Auto-configure RSocketGraphQlClient

This commit contributes a `RSocketGraphQlClient.Builder` component to
the context, pre-configured with the `RSocketStrategies`, a customized
`RSocketConnector` and the expected data MIME type.

See gh-30453

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/graphql/rsocket/RSocketGraphQlClientAutoConfiguration.java

@@ -0,0 +1,56 @@
+/*
+ * Copyright 2012-2022 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.
+ * You may obtain a copy of the License at
+ *
+ *      https://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.springframework.boot.autoconfigure.graphql.rsocket;
+
+import graphql.GraphQL;
+import io.rsocket.RSocket;
+import io.rsocket.transport.netty.client.TcpClientTransport;
+
+import org.springframework.boot.autoconfigure.AutoConfiguration;
+import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
+import org.springframework.boot.autoconfigure.rsocket.RSocketRequesterAutoConfiguration;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Scope;
+import org.springframework.graphql.client.RSocketGraphQlClient;
+import org.springframework.messaging.rsocket.RSocketRequester;
+import org.springframework.util.MimeTypeUtils;
+
+/**
+ * {@link EnableAutoConfiguration Auto-configuration} for {@link RSocketGraphQlClient}.
+ * This auto-configuration creates {@link RSocketGraphQlClient.Builder} prototype beans,
+ * as the builders are stateful and should not be reused to build client instances with
+ * different configurations.
+ *
+ * @author Brian Clozel
+ * @since 2.7.0
+ */
+@AutoConfiguration(after = RSocketRequesterAutoConfiguration.class)
+@ConditionalOnClass({ GraphQL.class, RSocketGraphQlClient.class, RSocketRequester.class, RSocket.class,
+		TcpClientTransport.class })
+public class RSocketGraphQlClientAutoConfiguration {
+
+	@Bean
+	@Scope("prototype")
+	@ConditionalOnMissingBean
+	public RSocketGraphQlClient.Builder<?> rsocketGraphQlClientBuilder(
+			RSocketRequester.Builder rsocketRequesterBuilder) {
+		return RSocketGraphQlClient.builder(rsocketRequesterBuilder.dataMimeType(MimeTypeUtils.APPLICATION_GRAPHQL));
+	}
+
+}

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/graphql/rsocket/RSocketGraphQlClientAutoConfigurationTests.java

@@ -0,0 +1,76 @@
+/*
+ * Copyright 2012-2022 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.
+ * You may obtain a copy of the License at
+ *
+ *      https://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.springframework.boot.autoconfigure.graphql.rsocket;
+
+import org.junit.jupiter.api.Test;
+
+import org.springframework.boot.autoconfigure.AutoConfigurations;
+import org.springframework.boot.autoconfigure.rsocket.RSocketRequesterAutoConfiguration;
+import org.springframework.boot.autoconfigure.rsocket.RSocketStrategiesAutoConfiguration;
+import org.springframework.boot.test.context.runner.ApplicationContextRunner;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.graphql.client.RSocketGraphQlClient;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Tests for {@link RSocketGraphQlClientAutoConfiguration}.
+ *
+ * @author Brian Clozel
+ */
+class RSocketGraphQlClientAutoConfigurationTests {
+
+	private static final RSocketGraphQlClient.Builder<?> builderInstance = RSocketGraphQlClient.builder();
+
+	private final ApplicationContextRunner contextRunner = new ApplicationContextRunner()
+			.withConfiguration(AutoConfigurations.of(RSocketStrategiesAutoConfiguration.class,
+					RSocketRequesterAutoConfiguration.class, RSocketGraphQlClientAutoConfiguration.class));
+
+	@Test
+	void shouldCreateBuilder() {
+		this.contextRunner.run((context) -> assertThat(context).hasSingleBean(RSocketGraphQlClient.Builder.class));
+	}
+
+	@Test
+	void shouldGetPrototypeScopedBean() {
+		this.contextRunner.run((context) -> {
+			RSocketGraphQlClient.Builder<?> first = context.getBean(RSocketGraphQlClient.Builder.class);
+			RSocketGraphQlClient.Builder<?> second = context.getBean(RSocketGraphQlClient.Builder.class);
+			assertThat(first).isNotEqualTo(second);
+		});
+	}
+
+	@Test
+	void shouldNotCreateBuilderIfAlreadyPresent() {
+		this.contextRunner.withUserConfiguration(CustomRSocketGraphQlClientBuilder.class).run((context) -> {
+			RSocketGraphQlClient.Builder<?> builder = context.getBean(RSocketGraphQlClient.Builder.class);
+			assertThat(builder).isEqualTo(builderInstance);
+		});
+	}
+
+	@Configuration(proxyBeanMethods = false)
+	static class CustomRSocketGraphQlClientBuilder {
+
+		@Bean
+		RSocketGraphQlClient.Builder<?> myRSocketGraphQlClientBuilder() {
+			return builderInstance;
+		}
+
+	}
+
+}

spring-boot-project/spring-boot-docs/src/docs/asciidoc/web/spring-graphql.adoc

@@ -117,13 +117,14 @@ Spring Boot supports many configuration properties under the `spring.graphql.cor
 
 RSocket is also supported as a transport, on top of WebSocket or TCP.
 Once the <<messaging#messaging.rsocket.server-auto-configuration,RSocket server is configured>>, we can configure our GraphQL handler on a particular route using configprop:spring.graphql.rsocket.mapping[].
-For example, configuring that mapping as `"graphql"` means we can use the `RSocketGraphQlClient` as follows.
+For example, configuring that mapping as `"graphql"` means we can use that as a route when sending requests with the `RSocketGraphQlClient`.
 
-For RSocket over TCP:
-include::code:RSocketGraphQlClientExample[tag=tcp]
+Spring Boot auto-configures a `RSocketGraphQlClient.Builder<?>` bean that you can inject in your components:
 
-For RSocket over WebSocket:
-include::code:RSocketGraphQlClientExample[tag=websocket]
+include::code:RSocketGraphQlClientExample[tag=builder]
+
+And then send a request:
+include::code:RSocketGraphQlClientExample[tag=request]
 
 
 [[web.graphql.exception-handling]]

spring-boot-project/spring-boot-docs/src/main/java/org/springframework/boot/docs/web/graphql/transports/rsocket/RSocketGraphQlClientExample.java

@@ -16,32 +16,29 @@
 
 package org.springframework.boot.docs.web.graphql.transports.rsocket;
 
-import java.net.URI;
 import java.time.Duration;
 
 import reactor.core.publisher.Mono;
 
 import org.springframework.graphql.client.RSocketGraphQlClient;
+import org.springframework.stereotype.Component;
 
+// tag::builder[]
+@Component
 public class RSocketGraphQlClientExample {
 
-	public void rsocketOverTcp() {
-		// tag::tcp[]
-		RSocketGraphQlClient client = RSocketGraphQlClient.builder().tcp("example.spring.io", 8181).route("graphql")
-				.build();
-		Mono<Book> book = client.document("{ bookById(id: \"book-1\"){ id name pageCount author } }")
-				.retrieve("bookById").toEntity(Book.class);
-		// end::tcp[]
-		book.block(Duration.ofSeconds(5));
+	private final RSocketGraphQlClient graphQlClient;
+
+	public RSocketGraphQlClientExample(RSocketGraphQlClient.Builder<?> builder) {
+		this.graphQlClient = builder.tcp("example.spring.io", 8181).route("graphql").build();
 	}
+	// end::builder[]
 
-	public void rsocketOverWebSocket() {
-		// tag::websocket[]
-		RSocketGraphQlClient client = RSocketGraphQlClient.builder()
-				.webSocket(URI.create("wss://example.spring.io/rsocket")).route("graphql").build();
-		Mono<Book> book = client.document("{ bookById(id: \"book-1\"){ id name pageCount author } }")
+	public void rsocketOverTcp() {
+		// tag::request[]
+		Mono<Book> book = this.graphQlClient.document("{ bookById(id: \"book-1\"){ id name pageCount author } }")
 				.retrieve("bookById").toEntity(Book.class);
-		// end::websocket[]
+		// end::request[]
 		book.block(Duration.ofSeconds(5));
 	}
 

spring-boot-project/spring-boot-docs/src/main/kotlin/org/springframework/boot/docs/web/graphql/transports/rsocket/RSocketGraphQlClientExample.kt

@@ -17,41 +17,21 @@
 package org.springframework.boot.docs.web.graphql.transports.rsocket
 
 import org.springframework.graphql.client.RSocketGraphQlClient
-import java.net.URI
+import org.springframework.stereotype.Component
 import java.time.Duration
 
+// tag::builder[]
+@Component
+class RSocketGraphQlClientExample(private val builder: RSocketGraphQlClient.Builder<*>) {
+// end::builder[]
 
-class RSocketGraphQlClientExample {
-
-	fun rsocketOverTcp() {
-		// tag::tcp[]
-		val client = RSocketGraphQlClient.builder()
-			.tcp("example.spring.io", 8181)
+	val graphQlClient = builder.tcp("example.spring.io", 8181)
 		.route("graphql")
 		.build()
-		val book = client.document(
-			"""
-			{
-				bookById(id: "book-1"){
-					id
-					name
-					pageCount
-					author
-				}
-			}				
-			""")
-			.retrieve("bookById").toEntity(Book::class.java)
-		// end::tcp[]
-		book.block(Duration.ofSeconds(5))
-	}
 
-	fun rsocketOverWebSocket() {
-		// tag::websocket[]
-		val client = RSocketGraphQlClient.builder()
-			.webSocket(URI.create("wss://example.spring.io/rsocket"))
-			.route("graphql")
-			.build()
-		val book = client.document(
+	fun rsocketOverTcp() {
+		// tag::request[]
+		val book = graphQlClient.document(
 			"""
 			{
 				bookById(id: "book-1"){
@@ -61,9 +41,10 @@ class RSocketGraphQlClientExample {
 					author
 				}
 			}				
-			""")
+			"""
+		)
 			.retrieve("bookById").toEntity(Book::class.java)
-		// end::websocket[]
+		// end::request[]
 		book.block(Duration.ofSeconds(5))
 	}