From b800b6f79dd538a8d9bead233a9c8bc4f632d009 Mon Sep 17 00:00:00 2001
From: minguncle <57527858+minguncle@users.noreply.github.com>
Date: Thu, 27 Mar 2025 15:53:30 +0800
Subject: [PATCH] feat: Support separate registration and published paths in
 WebMvcSseServerTransportProvider

Adds a new constructor to WebMvcSseServerTransportProvider that accepts separate
parameters for server registration paths and client-facing published paths.

This enhancement allows the provider to work correctly in environments with
servlet context paths or global URL prefixes (like Spring Boot's
spring.mvc.servlet.path) by:
- Using messageEndpoint for server-side router registration
- Using publishedMessageEndpoint when communicating with clients

The implementation maintains backward compatibility
---
 .../WebMvcSseServerTransportProvider.java     | 35 ++++++++++++++++++-
 1 file changed, 34 insertions(+), 1 deletion(-)

diff --git a/mcp-spring/mcp-spring-webmvc/src/main/java/io/modelcontextprotocol/server/transport/WebMvcSseServerTransportProvider.java b/mcp-spring/mcp-spring-webmvc/src/main/java/io/modelcontextprotocol/server/transport/WebMvcSseServerTransportProvider.java
index 65416b25..65545695 100644
--- a/mcp-spring/mcp-spring-webmvc/src/main/java/io/modelcontextprotocol/server/transport/WebMvcSseServerTransportProvider.java
+++ b/mcp-spring/mcp-spring-webmvc/src/main/java/io/modelcontextprotocol/server/transport/WebMvcSseServerTransportProvider.java
@@ -91,6 +91,8 @@ public class WebMvcSseServerTransportProvider implements McpServerTransportProvi
 
 	private final String sseEndpoint;
 
+	private final String publishedMessageEndpoint;
+
 	private final RouterFunction<ServerResponse> routerFunction;
 
 	private McpServerSession.Factory sessionFactory;
@@ -105,6 +107,36 @@ public class WebMvcSseServerTransportProvider implements McpServerTransportProvi
 	 */
 	private volatile boolean isClosing = false;
 
+	/**
+	 * Constructs a new WebMvcSseServerTransportProvider instance.
+	 *
+	 * @param objectMapper             The ObjectMapper to use for JSON serialization/deserialization
+	 *                                 of messages.
+	 * @param messageEndpoint          The endpoint URI where clients should send their JSON-RPC
+	 *                                 messages via HTTP POST. This endpoint will be communicated to clients through the
+	 *                                 SSE connection's initial endpoint event.
+	 * @param publishedMessageEndpoint The published endpoint URI that will be sent to clients
+	 *                                 (might differ from the actual messageEndpoint in case of proxies, load balancers, etc.)
+	 * @param sseEndpoint              The endpoint URI where clients establish their SSE connections.
+	 * @throws IllegalArgumentException if any parameter is null
+	 */
+	public WebMvcSseServerTransportProvider(ObjectMapper objectMapper, String messageEndpoint,
+											String publishedMessageEndpoint, String sseEndpoint) {
+		Assert.notNull(objectMapper, "ObjectMapper must not be null");
+		Assert.notNull(messageEndpoint, "Message endpoint must not be null");
+		Assert.notNull(publishedMessageEndpoint, "Published message endpoint must not be null");
+		Assert.notNull(sseEndpoint, "SSE endpoint must not be null");
+
+		this.objectMapper = objectMapper;
+		this.messageEndpoint = messageEndpoint;
+		this.publishedMessageEndpoint = publishedMessageEndpoint;
+		this.sseEndpoint = sseEndpoint;
+		this.routerFunction = RouterFunctions.route()
+				.GET(this.sseEndpoint, this::handleSseConnection)
+				.POST(this.messageEndpoint, this::handleMessage)
+				.build();
+	}
+
 	/**
 	 * Constructs a new WebMvcSseServerTransportProvider instance.
 	 * @param objectMapper The ObjectMapper to use for JSON serialization/deserialization
@@ -122,6 +154,7 @@ public WebMvcSseServerTransportProvider(ObjectMapper objectMapper, String messag
 
 		this.objectMapper = objectMapper;
 		this.messageEndpoint = messageEndpoint;
+		this.publishedMessageEndpoint = messageEndpoint;
 		this.sseEndpoint = sseEndpoint;
 		this.routerFunction = RouterFunctions.route()
 			.GET(this.sseEndpoint, this::handleSseConnection)
@@ -248,7 +281,7 @@ private ServerResponse handleSseConnection(ServerRequest request) {
 				try {
 					sseBuilder.id(sessionId)
 						.event(ENDPOINT_EVENT_TYPE)
-						.data(messageEndpoint + "?sessionId=" + sessionId);
+						.data(publishedMessageEndpoint + "?sessionId=" + sessionId);
 				}
 				catch (Exception e) {
 					logger.error("Failed to send initial endpoint event: {}", e.getMessage());