java-sdk/mcp-spring/mcp-spring-webflux
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Filename Latest commit message Latest commit date
Christian Tzolov c711f8315a feat: implement Streamable HTTP HttpClient transport and improve error handling (#337)
- Add HttpClientStreamableHttpTransport implementing the 2025-03-26 MCP specification
- Add ResponseSubscribers utility for handling different HTTP response body types
- Refactor HttpClientSseClientTransport to use reactive streams instead of FlowSseClient
  - Remove FlowSseClient in favor of reactive stream patterns
  - Use Disposable-based connection management instead of CountDownLatch
  - Replace message endpoint discovery with Sinks.One approach
- Improve error handling by replacing doOnError/onErrorResume with onErrorComplete
- Add test coverage for new Streamable HTTP transport
- Add resiliency tests for connection handling and session invalidation

BREAKING CHANGE: FlowSseClient has been removed in favor of reactive streams

Signed-off-by: Christian Tzolov <christian.tzolov@broadcom.com>

Co-authored-by: Dariusz Jędrzejczyk <dariusz.jedrzejczyk@broadcom.com>
2025-07-03 21:55:02 +02:00
..
src feat: implement Streamable HTTP HttpClient transport and improve error handling (#337) 2025-07-03 21:55:02 +02:00
pom.xml feat: WebClient Streamable HTTP support (#292) 2025-06-10 18:33:40 +02:00
README.md Module and Package restructoring 2025-01-29 13:40:53 +01:00

WebFlux SSE Transport

<dependency>
    <groupId>io.modelcontextprotocol.sdk</groupId>
    <artifactId>mcp-spring-webflux</artifactId>
</dependency>
String MESSAGE_ENDPOINT = "/mcp/message";

@Configuration
static class MyConfig {

    // SSE transport
	@Bean
	public WebFluxSseServerTransport sseServerTransport() {
		return new WebFluxSseServerTransport(new ObjectMapper(), "/mcp/message");
	}

	// Router function for SSE transport used by Spring WebFlux to start an HTTP
	// server.
	@Bean
	public RouterFunction<?> mcpRouterFunction(WebFluxSseServerTransport transport) {
		return transport.getRouterFunction();
	}

	@Bean
	public McpAsyncServer mcpServer(ServerMcpTransport transport, OpenLibrary openLibrary) {

		// Configure server capabilities with resource support
		var capabilities = McpSchema.ServerCapabilities.builder()
			.resources(false, true) // No subscribe support, but list changes notifications
			.tools(true) // Tool support with list changes notifications
			.prompts(true) // Prompt support with list changes notifications
			.logging() // Logging support
			.build();

		// Create the server with both tool and resource capabilities
		var server = McpServer.using(transport)
			.serverInfo("MCP Demo Server", "1.0.0")
			.capabilities(capabilities)
			.resources(systemInfoResourceRegistration())
			.prompts(greetingPromptRegistration())
			.tools(openLibraryToolRegistrations(openLibrary))
			.async();
		
		return server;
	} 

    // ...

}