ASGI Mental Model¶

Lilya is ASGI-first. Understanding ASGI's scope, receive, and send explains most Lilya behavior.

Core contract¶

• scope: immutable connection/request metadata
• receive: inbound event stream (request body, websocket frames)
• send: outbound event stream (response start/body, websocket frames)

Lilya wraps this contract into higher-level abstractions such as:

• Request
• Response
• WebSocket
• Middleware

How Lilya maps the contract¶

• App entry receives ASGI triplet
• Router resolves route chain
• Dependency and permission layers are applied
• Handler returns a response object or serializable value
• Response emits ASGI messages through send

Why this matters¶

If you can reason about ASGI events, debugging middleware, streaming, websockets, and lifecycle hooks becomes predictable.

Related concepts¶

• Request Lifecycle
• Layering and Precedence

Next steps¶

• Request
• Middleware