Files
DocsGPT/application/mcp_server.py
Alex c06888bc86 feat: asgi and search service (#2424)
* feat: asgi and search service

* feat: asgi and mcp tool server

* fix: asgi issues

* fix: mini cors hardening
2026-04-23 12:21:39 +01:00

60 lines
1.9 KiB
Python

"""FastMCP server exposing DocsGPT retrieval over streamable HTTP.
Mounted at ``/mcp`` by ``application/asgi.py``. Bearer tokens are the
existing DocsGPT agent API keys — no new credential surface.
The tool reads the ``Authorization`` header directly via
``get_http_headers(include={"authorization"})``. The ``include`` kwarg
is required: by default ``get_http_headers`` strips ``authorization``
(and a handful of other hop-by-hop headers) so they aren't forwarded
to downstream services — since we deliberately want the caller's
token, we opt it back in.
"""
from __future__ import annotations
import asyncio
import logging
from fastmcp import FastMCP
from fastmcp.server.dependencies import get_http_headers
from application.services.search_service import (
InvalidAPIKey,
SearchFailed,
search,
)
logger = logging.getLogger(__name__)
mcp = FastMCP("docsgpt")
def _extract_bearer_token() -> str | None:
auth = get_http_headers(include={"authorization"}).get("authorization", "")
parts = auth.split(None, 1)
if len(parts) != 2 or parts[0].lower() != "bearer" or not parts[1]:
return None
return parts[1]
@mcp.tool
async def search_docs(query: str, chunks: int = 5) -> list[dict]:
"""Search the caller's DocsGPT knowledge base.
Authentication is via ``Authorization: Bearer <agent-api-key>`` on
the MCP request — the same opaque key that ``/api/search`` accepts
in its JSON body. Returns at most ``chunks`` hits, each a dict with
``text``, ``title``, ``source`` keys.
"""
api_key = _extract_bearer_token()
if not api_key:
raise PermissionError("Missing Bearer token")
try:
return await asyncio.to_thread(search, api_key, query, chunks)
except InvalidAPIKey as exc:
raise PermissionError("Invalid API key") from exc
except SearchFailed:
logger.exception("search_docs failed")
raise