• Allow path parameters to have default values (e.g. None) and discard them instead of raising an error.
  • This allows declaring a parameter like user_id: str = None that can be taken from a query parameter, but the same path operation can be included in a router with a path /users/{user_id}, in which case will be taken from the path and will be required.
  • PR #464 by @jonathanunderwood.
• Add support for setting a default_response_class in the FastAPI instance or in include_router. Initial PR #467 by @toppk.
• Add support for type annotations using strings and from __future__ import annotations. PR #451 by @dmontagu.