o iJ*@sdZddlZddlmZddlmZddlmZddlm Z m Z ddl Z ddl m Z mZddlmZdd lmZdd lmZdd lmZdd lmZmZmZddlmZdd lmZmZddl m!Z!m"Z"e#e$Z%GdddZ&dS)a SSE Server Transport Module This module implements a Server-Sent Events (SSE) transport layer for MCP servers. Example usage: ``` # Create an SSE transport at an endpoint sse = SseServerTransport("/messages/") # Create Starlette routes for SSE and message handling routes = [ Route("/sse", endpoint=handle_sse, methods=["GET"]), Mount("/messages/", app=sse.handle_post_message), ] # Define handler functions async def handle_sse(request): async with sse.connect_sse( request.scope, request.receive, request._send ) as streams: await app.run( streams[0], streams[1], app.create_initialization_options() ) # Return empty response to avoid NoneType error return Response() # Create and run Starlette app starlette_app = Starlette(routes=routes) uvicorn.run(starlette_app, host="127.0.0.1", port=port) ``` Note: The handle_sse function must return a Response to avoid a "TypeError: 'NoneType' object is not callable" error when client disconnects. The example above returns an empty Response() after the SSE connection ends to fix this. See SseServerTransport class documentation for more details. N)asynccontextmanager)Any)quote)UUIDuuid4)MemoryObjectReceiveStreamMemoryObjectSendStream)ValidationError)EventSourceResponse)Request)Response)ReceiveScopeSend)TransportSecurityMiddlewareTransportSecuritySettings)ServerMessageMetadataSessionMessagecseZdZUdZeed<eeee e Bfed<e ed<ddede dBddffd d Z ed ed ed efddZd ed ed eddfddZZS)SseServerTransporta SSE server transport for MCP. This class provides _two_ ASGI applications, suitable to be used with a framework like Starlette and a server like Hypercorn: 1. connect_sse() is an ASGI application which receives incoming GET requests, and sets up a new SSE stream to send server messages to the client. 2. handle_post_message() is an ASGI application which receives incoming POST requests, which should contain client messages that link to a previously-established SSE session. _endpoint_read_stream_writers _securityNendpointsecurity_settingsreturncsxtd|vs|dsd|vsd|vrtd|d|ds'd|}||_i|_t||_t d|d S) a Creates a new SSE server transport, which will direct the client to POST messages to the relative path given. Args: endpoint: A relative path where messages should be posted (e.g., "/messages/"). security_settings: Optional security settings for DNS rebinding protection. Note: We use relative paths instead of full URLs for several reasons: 1. Security: Prevents cross-origin requests by ensuring clients only connect to the same origin they established the SSE connection with 2. Flexibility: The server can be mounted at any path without needing to know its full URL 3. Portability: The same endpoint configuration works across different environments (development, staging, production) Raises: ValueError: If the endpoint is a full URL instead of a relative path z://z//?#zGiven endpoint: z] is not a relative path (e.g., '/messages/'), expecting a relative path (e.g., '/messages/')./z.SseServerTransport initialized with endpoint: N) super__init__ startswith ValueErrorrrrrloggerdebug)selfrr __class__E/home/app/Keep/.python/lib/python3.10/site-packages/mcp/server/sse.pyrPs "   zSseServerTransport.__init__scopereceivesendc s|ddkrtdtdt||}|jj|ddIdH}|r/||||IdHtdtdtd \}td \}t |j <td | d d }| d |j } t| djtjtttfd \fddt4IdH4} dtdtdtffdd } td| | |||td||fVWdIdHdS1IdHswYdS)Ntypehttpz%connect_sse received non-HTTP requestz)connect_sse can only handle HTTP requestsFZis_postzRequest validation failedzSetting up SSE connectionrzCreated new session with ID: root_pathrz ?session_id=c std4IdH^4IdHAddIdHtd2z3dHW}td|d|jjddddIdHq)6WdIdHn 1IdHsZwYWdIdHdS1IdHspwYdS) NzStarting SSE writerr)eventdatazSent endpoint event: zSending message via SSE: messageT)Zby_aliasZ exclude_none)r"r#r+r3Zmodel_dump_json)session_message)client_post_uri_datasse_stream_writerwrite_stream_readerr'r( sse_writers  Xz2SseServerTransport.connect_sse..sse_writerr)r*r+csLtd|||IdHIdHIdHtddS)z The EventSourceResponse returning signals a client close / disconnect. 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