[vjymisal0]

Summary

This PR adds a zero-dependency, native ASGI 3.0 Interface Adapter (ASGIAdapter) to Bottle with support for:

1. Asynchronous Route Handlers: Full support for async def coroutine routes and returned awaitable objects alongside standard synchronous routes.
2. Lifespan Protocol: Seamless ASGI lifespan handling (lifespan.startup, lifespan.shutdown) with corresponding application hooks (asgi_startup, asgi_shutdown).
3. Chunked Body Streaming: Handles streaming request bodies and chunked response streaming (including async generators / iterators).
4. Convenient App Properties & Uvicorn Adapter:
   • app.to_asgi() and app.asgi property for direct mounting in ASGI servers (Uvicorn, Hypercorn, Granian).
   • UvicornServer server adapter in server_names (run(app, server='uvicorn')).

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Motivation

While WSGI is battle-tested, modern Python server infrastructure increasingly runs on ASGI-native servers (such as Uvicorn, Hypercorn, Granian) and async ecosystems. Adding a native, zero-dependency ASGI 3.0 adapter allows developers to deploy Bottle applications directly on modern ASGI servers and mix async def route handlers without requiring third-party WSGI-to-ASGI wrapper packages.

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Key Additions

• ASGIAdapter: Converts ASGI scopes (http, lifespan, websocket) and receive/send streams to Bottle's dispatch pipeline.
• Bottle.asgi / Bottle.to_asgi(): Directly exposes the ASGI entry point on any Bottle application instance.
• UvicornServer: Registered in server_names['uvicorn'] for easy run(server='uvicorn') execution.
• Hook Expansion: Added 'asgi_startup' and 'asgi_shutdown' lifecycle hooks to Bottle.

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Verification

• Added test/test_asgi.py with 9 comprehensive tests:
  • HTTP GET/POST handling with JSON payloads
  • Asynchronous coroutine route execution (async def)
  • Query parameters and dynamic route arguments
  • Custom status codes and header manipulation
  • 404 Not Found and 500 Internal Error handling
  • Lifespan startup and shutdown events
• Ran full test suite (python -m unittest discover -t . -s test) — all 387 tests passing.

[defnull]

No, because obvious DoS vulnerability and broken handling of thread-locals and blocking route handlers or plugins.