feat(mcp): refactor MCP transport configuration to use dedicated starters

auto-configurations/spring-ai-mcp-client/pom.xml

@@ -0,0 +1,74 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+		 xmlns="http://maven.apache.org/POM/4.0.0"
+		 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
+	<modelVersion>4.0.0</modelVersion>
+	<parent>
+		<groupId>org.springframework.ai</groupId>
+		<artifactId>spring-ai</artifactId>
+		<version>1.0.0-SNAPSHOT</version>
+		<relativePath>../../pom.xml</relativePath>
+	</parent>
+	<artifactId>spring-ai-mcp-client-spring-boot-autoconfigure</artifactId>
+	<packaging>jar</packaging>
+	<name>Spring AI MCP Client Auto Configuration</name>
+	<description>Spring AI MCP Client Auto Configuration</description>
+	<url>https://github.com/spring-projects/spring-ai</url>
+
+	<scm>
+		<url>https://github.com/spring-projects/spring-ai</url>
+		<connection>git://github.com/spring-projects/spring-ai.git</connection>
+		<developerConnection>[email protected]:spring-projects/spring-ai.git</developerConnection>
+	</scm>
+
+
+	<dependencies>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter</artifactId>
+		</dependency>
+
+		<dependency>
+			<groupId>org.springframework.ai</groupId>
+			<artifactId>spring-ai-mcp</artifactId>
+			<version>${project.parent.version}</version>
+			<optional>true</optional>
+		</dependency>
+
+		<dependency>
+			<groupId>io.modelcontextprotocol.sdk</groupId>
+			<artifactId>mcp-spring-webflux</artifactId>
+			<optional>true</optional>
+		</dependency>
+
+		<!-- NOTE: Currently the webmvc doesn't implement client transport. 
+			We will add it in the future based on ResrtClient.
+		-->
+		<!-- <dependency>
+			<groupId>io.modelcontextprotocol.sdk</groupId>
+			<artifactId>mcp-spring-webmvc</artifactId>
+			<optional>true</optional>
+		</dependency> -->
+
+		<!-- Test dependencies -->
+		<dependency>
+			<groupId>org.springframework.ai</groupId>
+			<artifactId>spring-ai-test</artifactId>
+			<version>${project.parent.version}</version>
+			<scope>test</scope>
+		</dependency>
+
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-test</artifactId>
+			<scope>test</scope>
+		</dependency>
+
+		<dependency>
+			<groupId>org.mockito</groupId>
+			<artifactId>mockito-core</artifactId>
+			<scope>test</scope>
+		</dependency>
+	</dependencies>
+
+</project>

auto-configurations/spring-ai-mcp-client/src/main/java/org/springframework/ai/autoconfigure/mcp/client/McpClientAutoConfiguration.java

@@ -0,0 +1,293 @@
+/*
+ * Copyright 2025-2025 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.ai.autoconfigure.mcp.client;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import io.modelcontextprotocol.client.McpAsyncClient;
+import io.modelcontextprotocol.client.McpClient;
+import io.modelcontextprotocol.client.McpSyncClient;
+import io.modelcontextprotocol.spec.McpSchema;
+
+import org.springframework.ai.autoconfigure.mcp.client.configurer.McpAsyncClientConfigurer;
+import org.springframework.ai.autoconfigure.mcp.client.configurer.McpSyncClientConfigurer;
+import org.springframework.ai.autoconfigure.mcp.client.properties.McpClientCommonProperties;
+import org.springframework.ai.mcp.McpToolUtils;
+import org.springframework.ai.mcp.customizer.McpAsyncClientCustomizer;
+import org.springframework.ai.mcp.customizer.McpSyncClientCustomizer;
+import org.springframework.ai.tool.ToolCallback;
+import org.springframework.beans.factory.ObjectProvider;
+import org.springframework.boot.autoconfigure.AutoConfiguration;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
+import org.springframework.boot.context.properties.EnableConfigurationProperties;
+import org.springframework.context.annotation.Bean;
+import org.springframework.util.CollectionUtils;
+
+/**
+ * Auto-configuration for Model Context Protocol (MCP) client support.
+ *
+ * <p>
+ * This configuration class sets up the necessary beans for MCP client functionality,
+ * including both synchronous and asynchronous clients along with their respective tool
+ * callbacks. It is automatically enabled when the required classes are present on the
+ * classpath and can be explicitly disabled through properties.
+ *
+ * <p>
+ * Configuration Properties:
+ * <ul>
+ * <li>{@code spring.ai.mcp.client.enabled} - Enable/disable MCP client support (default:
+ * true)
+ * <li>{@code spring.ai.mcp.client.type} - Client type: SYNC or ASYNC (default: SYNC)
+ * <li>{@code spring.ai.mcp.client.name} - Client implementation name
+ * <li>{@code spring.ai.mcp.client.version} - Client implementation version
+ * <li>{@code spring.ai.mcp.client.request-timeout} - Request timeout duration
+ * <li>{@code spring.ai.mcp.client.initialized} - Whether to initialize clients on
+ * creation
+ * </ul>
+ *
+ * <p>
+ * The configuration is activated after the transport-specific auto-configurations (Stdio,
+ * SSE HTTP, and SSE WebFlux) to ensure proper initialization order. At least one
+ * transport must be available for the clients to be created.
+ *
+ * <p>
+ * Key features:
+ * <ul>
+ * <li>Synchronous and Asynchronous Client Support:
+ * <ul>
+ * <li>Creates and configures MCP clients based on available transports
+ * <li>Supports both blocking (sync) and non-blocking (async) operations
+ * <li>Automatic client initialization if enabled
+ * </ul>
+ * <li>Integration Support:
+ * <ul>
+ * <li>Sets up tool callbacks for Spring AI integration
+ * <li>Supports multiple named transports
+ * <li>Proper lifecycle management with automatic cleanup
+ * </ul>
+ * <li>Customization Options:
+ * <ul>
+ * <li>Extensible through {@link McpSyncClientCustomizer} and
+ * {@link McpAsyncClientCustomizer}
+ * <li>Configurable timeouts and client information
+ * <li>Support for custom transport implementations
+ * </ul>
+ * </ul>
+ *
+ * @see McpSyncClient
+ * @see McpAsyncClient
+ * @see McpClientCommonProperties
+ * @see McpSyncClientCustomizer
+ * @see McpAsyncClientCustomizer
+ * @see StdioTransportAutoConfiguration
+ * @see SseHttpClientTransportAutoConfiguration
+ * @see SseWebFluxTransportAutoConfiguration
+ */
+@AutoConfiguration(after = { StdioTransportAutoConfiguration.class, SseHttpClientTransportAutoConfiguration.class,
+		SseWebFluxTransportAutoConfiguration.class })
+@ConditionalOnClass({ McpSchema.class })
+@EnableConfigurationProperties(McpClientCommonProperties.class)
+@ConditionalOnProperty(prefix = McpClientCommonProperties.CONFIG_PREFIX, name = "enabled", havingValue = "true",
+		matchIfMissing = true)
+public class McpClientAutoConfiguration {
+
+	/**
+	 * Creates a list of {@link McpSyncClient} instances based on the available
+	 * transports.
+	 *
+	 * <p>
+	 * Each client is configured with:
+	 * <ul>
+	 * <li>Client information (name and version) from common properties
+	 * <li>Request timeout settings
+	 * <li>Custom configurations through {@link McpSyncClientConfigurer}
+	 * </ul>
+	 *
+	 * <p>
+	 * If initialization is enabled in properties, the clients are automatically
+	 * initialized.
+	 * @param mcpSyncClientConfigurer the configurer for customizing client creation
+	 * @param commonProperties common MCP client properties
+	 * @param transportsProvider provider of named MCP transports
+	 * @return list of configured MCP sync clients
+	 */
+	@Bean
+	@ConditionalOnProperty(prefix = McpClientCommonProperties.CONFIG_PREFIX, name = "type", havingValue = "SYNC",
+			matchIfMissing = true)
+	public List<McpSyncClient> mcpSyncClients(McpSyncClientConfigurer mcpSyncClientConfigurer,
+			McpClientCommonProperties commonProperties,
+			ObjectProvider<List<NamedClientMcpTransport>> transportsProvider) {
+
+		List<McpSyncClient> mcpSyncClients = new ArrayList<>();
+
+		List<NamedClientMcpTransport> namedTransports = transportsProvider.stream().flatMap(List::stream).toList();
+
+		if (!CollectionUtils.isEmpty(namedTransports)) {
+			for (NamedClientMcpTransport namedTransport : namedTransports) {
+
+				McpSchema.Implementation clientInfo = new McpSchema.Implementation(commonProperties.getName(),
+						commonProperties.getVersion());
+
+				McpClient.SyncSpec syncSpec = McpClient.sync(namedTransport.transport())
+					.clientInfo(clientInfo)
+					.requestTimeout(commonProperties.getRequestTimeout());
+
+				syncSpec = mcpSyncClientConfigurer.configure(namedTransport.name(), syncSpec);
+
+				var syncClient = syncSpec.build();
+
+				if (commonProperties.isInitialized()) {
+					syncClient.initialize();
+				}
+
+				mcpSyncClients.add(syncClient);
+			}
+		}
+
+		return mcpSyncClients;
+	}
+
+	/**
+	 * Creates tool callbacks for all configured MCP clients.
+	 *
+	 * <p>
+	 * These callbacks enable integration with Spring AI's tool execution framework,
+	 * allowing MCP tools to be used as part of AI interactions.
+	 * @param mcpClientsProvider provider of MCP sync clients
+	 * @return list of tool callbacks for MCP integration
+	 */
+	@Bean
+	@ConditionalOnProperty(prefix = McpClientCommonProperties.CONFIG_PREFIX, name = "type", havingValue = "SYNC",
+			matchIfMissing = true)
+	public List<ToolCallback> toolCallbacks(ObjectProvider<List<McpSyncClient>> mcpClientsProvider) {
+		List<McpSyncClient> mcpClients = mcpClientsProvider.stream().flatMap(List::stream).toList();
+		return McpToolUtils.getToolCallbacksFromSyncClients(mcpClients);
+	}
+
+	/**
+	 * Record class that implements {@link AutoCloseable} to ensure proper cleanup of MCP
+	 * clients.
+	 *
+	 * <p>
+	 * This class is responsible for closing all MCP sync clients when the application
+	 * context is closed, preventing resource leaks.
+	 */
+	public record ClosebleMcpSyncClients(List<McpSyncClient> clients) implements AutoCloseable {
+
+		@Override
+		public void close() {
+			this.clients.forEach(McpSyncClient::close);
+		}
+	}
+
+	/**
+	 * Creates a closeable wrapper for MCP sync clients to ensure proper resource cleanup.
+	 * @param clients the list of MCP sync clients to manage
+	 * @return a closeable wrapper for the clients
+	 */
+	@Bean
+	@ConditionalOnProperty(prefix = McpClientCommonProperties.CONFIG_PREFIX, name = "type", havingValue = "SYNC",
+			matchIfMissing = true)
+	public ClosebleMcpSyncClients makeSyncClientsClosable(List<McpSyncClient> clients) {
+		return new ClosebleMcpSyncClients(clients);
+	}
+
+	/**
+	 * Creates the default {@link McpSyncClientConfigurer} if none is provided.
+	 *
+	 * <p>
+	 * This configurer aggregates all available {@link McpSyncClientCustomizer} instances
+	 * to allow for customization of MCP sync client creation.
+	 * @param customizerProvider provider of MCP sync client customizers
+	 * @return the configured MCP sync client configurer
+	 */
+	@Bean
+	@ConditionalOnMissingBean
+	@ConditionalOnProperty(prefix = McpClientCommonProperties.CONFIG_PREFIX, name = "type", havingValue = "SYNC",
+			matchIfMissing = true)
+	McpSyncClientConfigurer mcpSyncClientConfigurer(ObjectProvider<McpSyncClientCustomizer> customizerProvider) {
+		return new McpSyncClientConfigurer(customizerProvider.orderedStream().toList());
+	}
+
+	// Async client configuration
+
+	@Bean
+	@ConditionalOnProperty(prefix = McpClientCommonProperties.CONFIG_PREFIX, name = "type", havingValue = "ASYNC")
+	public List<McpAsyncClient> mcpAsyncClients(McpAsyncClientConfigurer mcpSyncClientConfigurer,
+			McpClientCommonProperties commonProperties,
+			ObjectProvider<List<NamedClientMcpTransport>> transportsProvider) {
+
+		List<McpAsyncClient> mcpSyncClients = new ArrayList<>();
+
+		List<NamedClientMcpTransport> namedTransports = transportsProvider.stream().flatMap(List::stream).toList();
+
+		if (!CollectionUtils.isEmpty(namedTransports)) {
+			for (NamedClientMcpTransport namedTransport : namedTransports) {
+
+				McpSchema.Implementation clientInfo = new McpSchema.Implementation(commonProperties.getName(),
+						commonProperties.getVersion());
+
+				McpClient.AsyncSpec syncSpec = McpClient.async(namedTransport.transport())
+					.clientInfo(clientInfo)
+					.requestTimeout(commonProperties.getRequestTimeout());
+
+				syncSpec = mcpSyncClientConfigurer.configure(namedTransport.name(), syncSpec);
+
+				var syncClient = syncSpec.build();
+
+				if (commonProperties.isInitialized()) {
+					syncClient.initialize();
+				}
+
+				mcpSyncClients.add(syncClient);
+			}
+		}
+
+		return mcpSyncClients;
+	}
+
+	@Bean
+	@ConditionalOnProperty(prefix = McpClientCommonProperties.CONFIG_PREFIX, name = "type", havingValue = "ASYNC")
+	public List<ToolCallback> asyncToolCallbacks(ObjectProvider<List<McpAsyncClient>> mcpClientsProvider) {
+		List<McpAsyncClient> mcpClients = mcpClientsProvider.stream().flatMap(List::stream).toList();
+		return McpToolUtils.getToolCallbacksFromAsyncClinents(mcpClients);
+	}
+
+	public record ClosebleMcpAsyncClients(List<McpAsyncClient> clients) implements AutoCloseable {
+		@Override
+		public void close() {
+			this.clients.forEach(McpAsyncClient::close);
+		}
+	}
+
+	@Bean
+	@ConditionalOnProperty(prefix = McpClientCommonProperties.CONFIG_PREFIX, name = "type", havingValue = "ASYNC")
+	public ClosebleMcpAsyncClients makeAsynClientsClosable(List<McpAsyncClient> clients) {
+		return new ClosebleMcpAsyncClients(clients);
+	}
+
+	@Bean
+	@ConditionalOnMissingBean
+	@ConditionalOnProperty(prefix = McpClientCommonProperties.CONFIG_PREFIX, name = "type", havingValue = "ASYNC")
+	McpAsyncClientConfigurer mcpAsyncClientConfigurer(ObjectProvider<McpAsyncClientCustomizer> customizerProvider) {
+		return new McpAsyncClientConfigurer(customizerProvider.orderedStream().toList());
+	}
+
+}