Add first-class REST/OAuth provider type

[BillJr99]

Introduce a new rest provider kind so a REST API can be wrapped as MCP
tools declaratively — no Python required. A provider YAML with a rest:
block declares a base URL, an auth: block, and endpoints (entered by
hand or imported from an OpenAPI 3.0 spec); each endpoint becomes an MCP
tool exposed on both the MCP server (8888) and the OpenAI-compatible REST
API (8889).

• rest_provider.py: generic httpx handler routed through register_tool,
  a client_credentials token manager (cache/refresh), an
  authorization_code + PKCE token store (on-disk cache, interactive
  browser flow, refresh-token rotation), an auth resolver, and an
  OpenAPI 3.0 introspector.
• server.py: a rest branch in register_provider (checked first; each
  tool maps 1:1 to an endpoint by name).
• frontend/app.py: "REST / OAuth API" wizard step (auth-type fields,
  OpenAPI import + manual endpoints), editor rest-box with an Authorize
  button, plus /api/introspect-openapi, /api/rest-authorize, and
  /oauth/callback endpoints; pending auth links surface in the existing
  banner.
• config.py / run_local.sh / docker-compose.yml: REST_AUTH_DIR and
  OAUTH_REDIRECT_BASE settings and token-cache volume.
• requirements.txt: httpx promoted to a runtime dependency.
• Tests: tests/test_rest_provider.py plus rest cases in test_server.py
  and test_frontend.py (387 passing).

https://claude.ai/code/session_01L9uGbkXi2RwUmBQHdVaNoZ

[Copilot]

Pull request overview

This PR adds a first-class rest provider type so users can declaratively wrap REST APIs as MCP tools (including OAuth flows), without writing Python code. It introduces a REST provider runtime (rest_provider.py), wires REST provider registration into the MCP server, and extends the UI to create/edit REST providers and run OAuth authorization_code + PKCE.

Changes:

• Added rest_provider.py with REST request handling, auth resolvers (none/bearer/api_key/OAuth), token caching, and OpenAPI/Swagger introspection.
• Updated server registration to support rest: providers and added startup warm-up for OAuth-backed REST providers.
• Extended the frontend to support a “REST / OAuth API” wizard/editor, OpenAPI introspection endpoint, and OAuth callback/authorize endpoints; added comprehensive tests.

Reviewed changes

Copilot reviewed 10 out of 12 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
server.py	Registers REST providers and adds REST OAuth warm-up on startup.
rest_provider.py	Implements REST tool handler, OAuth token management, and OpenAPI/Swagger parsing.
frontend/app.py	Adds REST provider CRUD support in UI, OpenAPI introspection API, and OAuth authorize/callback endpoints plus editor/wizard UI.
README.md	Documents REST/OAuth providers, auth modes, example YAML, and config knobs.
config.py	Adds REST_AUTH_DIR and OAUTH_REDIRECT_BASE settings.
docker-compose.yml	Persists REST OAuth token cache via a new volume and env var.
run_local.sh	Adds local default for MCPPROXY_REST_AUTH_DIR.
requirements.txt	Adds httpx as a runtime dependency.
.gitignore	Ignores .rest-auth/ token cache directory.
tests/test_rest_provider.py	Adds unit tests for REST provider behavior, OAuth managers, and OpenAPI parsing.
tests/test_server.py	Adds tests for REST branch detection and OAuth REST provider discovery.
tests/test_frontend.py	Adds REST provider UI/backend tests including wizard flow and OAuth endpoints.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.