From 81b40e5608b14a8732023e0f5315fd39e7d153f3 Mon Sep 17 00:00:00 2001
From: Justin Spahr-Summers <justin@anthropic.com>
Date: Fri, 27 Sep 2024 11:14:59 +0100
Subject: [PATCH] Add SSEServerTransport.handleMessage bypass

---
 src/server/sse.ts | 20 +++++++++++++++-----
 1 file changed, 15 insertions(+), 5 deletions(-)

diff --git a/src/server/sse.ts b/src/server/sse.ts
index 26970de9..7dd10186 100644
--- a/src/server/sse.ts
+++ b/src/server/sse.ts
@@ -88,20 +88,30 @@ export class SSEServerTransport implements Transport {
       return;
     }
 
-    let message: JSONRPCMessage;
     try {
-      message = JSON.parse(body);
-      validateMessage(message);
+      await this.handleMessage(JSON.parse(body));
     } catch (error) {
-      this.onerror?.(error as Error);
       res.writeHead(400).end(`Invalid message: ${body}`);
       return;
     }
 
-    this.onmessage?.(message);
     res.writeHead(202).end("Accepted");
   }
 
+  /**
+   * Handle a client message, regardless of how it arrived. This can be used to inform the server of messages that arrive via a means different than HTTP POST.
+   */
+  async handleMessage(message: JSONRPCMessage): Promise<void> {
+    try {
+      validateMessage(message);
+    } catch (error) {
+      this.onerror?.(error as Error);
+      return;
+    }
+
+    this.onmessage?.(message);
+  }
+
   async close(): Promise<void> {
     this._sseResponse?.end();
     this._sseResponse = undefined;