Connexion 3 is out now! 🎉

[RobbeSneyders]

We are excited to announce the release of Connexion 3.0! 🎉

Connexion 3 fundamentally changes how Connexion is designed and implemented, and how it
fits into the wider Python API ecosystem. We adopted the ASGI interface, which makes Connexion both
modular and well-integrated with most modern Python API tooling.

It brings some major changes compared to 2.X:

• The improved App and new AsyncApp allow you to use Connexion as a stand-alone framework
  • The App interface was extended so you no longer have to care about the framework used
    underneath
• Connexion can now be used as middleware to supercharge any ASGI or WSGI-compatible framework
  with its spec-based functionality
• Connexion is now pluggable in many dimensions:
  • All Connexion functionality is pluggable by adding or removing middleware from its stack
  • Validation is now pluggable by content type, solving longstanding issues regarding endpoints
    with multiple content types and making it easy to add validation for additional content types
  • Authentication is now pluggable by security scheme, making it easy to customize the behavior or
    add support for additional security schemes.
• Aiohttp support has been dropped due to lack of ASGI support
• We spent a lot of effort on extending and improving our documentation_

For further details, check:

• Our Connexion 3 documentation page for a high level overview of the changes
• Our in-depth blog post on the redesign for technical details
• The release for a detailed overview of all changes 👇

[RobbeSneyders]

Locking this. Please discuss in #1775.