litellm/tests/test_litellm/proxy/_experimental
tin-berri d193c7aefe
fix(mcp): strip root_path before matching the per-server MCP route spelling (#35576)
* fix(mcp): strip root_path before matching the per-server MCP route spelling

The 401 challenge for a gateway-managed oauth2 MCP server advertises the
protected-resource metadata URL in the spelling the client connected on, so a
strict RFC 9728 section 3 client lands on a document whose `resource` equals the
URL it actually called. That spelling test compared `_original_path` against the
root-relative `/{server}/mcp` shape, but `_original_path` and `scope["path"]`
are raw request-line paths that still carry the deployment's `root_path`

On a SERVER_ROOT_PATH deployment the prefix therefore made the legacy test fail
and every request fell through to the standard `/mcp/{server}` branch. A client
connecting on `/litellm/github/mcp` was pointed at the standard-pattern
document, which serves `resource = {base}/litellm/mcp/github`; that is not the
URL the client called, so a strict client aborts discovery before the MCP
request fires

Route the path through `get_route_relative_request_path` first, which removes
`root_path` on a segment boundary the same way
`litellm.proxy.auth.auth_utils.get_request_route` already does for the rest of
the MCP auth path, so `/litellmfoo` is not truncated under `root_path=/litellm`

* fix(mcp): make the gateway-managed 401 challenge root-path aware

The gateway-managed authorization_code challenge in process_mcp_request
built its AS-metadata URL from two root-path-unaware pieces:

- it matched the caller's spelling against `scope["_original_path"]`, a
  raw request-line path that still carries the deployment prefix, so on a
  SERVER_ROOT_PATH deployment the `/mcp/{server}` branch never matched and
  every request fell through to the legacy one-segment form
- it hardcoded `/.well-known/oauth-authorization-server` without the
  root-path segment the discovery route decorators bake in, so the URL
  404'd under a sub-path deployment regardless of which branch was taken

Route the spelling match through get_route_relative_request_path and the
well-known root through well_known_root_suffix, the same two helpers the
discovery route registrations derive their paths from, so the advertised
URL cannot drift from the route that serves it.

Root-mounted deployments are unaffected: both helpers are no-ops when
SERVER_ROOT_PATH is unset.

Co-Authored-By: Claude <noreply@anthropic.com>

---------

Co-authored-by: Claude <noreply@anthropic.com>
2026-08-21 15:40:14 -07:00
..
mcp_server fix(mcp): strip root_path before matching the per-server MCP route spelling (#35576) 2026-08-21 15:40:14 -07:00