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sozu_lib/protocol/
mod.rs

1//! Protocol-state surface area.
2//!
3//! Defines the [`SessionState`] trait that every front-end protocol
4//! implementation (`kawa_h1`, `mux`, `pipe`, `proxy_protocol`, `rustls`)
5//! plugs into the mio worker loop. State implementations decide how to
6//! react to readiness events, manage timeouts, render their internal state
7//! for debugging, and signal whether the session can be torn down.
8
9pub mod kawa_h1;
10pub mod mux;
11pub mod pipe;
12pub mod proxy_protocol;
13pub mod rustls;
14
15use std::{cell::RefCell, rc::Rc};
16
17use mio::Token;
18use sozu_command::ready::Ready;
19
20pub use crate::protocol::{
21    http::Http, kawa_h1 as http, pipe::Pipe, proxy_protocol::send::SendProxyProtocol,
22    rustls::TlsHandshake,
23};
24use crate::{
25    L7Proxy, ProxySession, SessionIsToBeClosed, SessionMetrics, SessionResult, StateResult,
26};
27
28/// All States should satisfy this trait in order to receive and handle Session events
29pub trait SessionState {
30    /// if a session received an event or can still execute, the event loop will
31    /// call this method. Its result indicates if it can still execute or if the
32    /// session can be closed
33    fn ready(
34        &mut self,
35        session: Rc<RefCell<dyn ProxySession>>,
36        proxy: Rc<RefCell<dyn L7Proxy>>,
37        metrics: &mut SessionMetrics,
38    ) -> SessionResult;
39    /// if the event loop got an event for a token associated with the session,
40    /// it will call this method
41    fn update_readiness(&mut self, token: Token, events: Ready);
42    /// close the state
43    fn close(&mut self, _proxy: Rc<RefCell<dyn L7Proxy>>, _metrics: &mut SessionMetrics) {}
44    /// if a timeout associated with the session triggers, the event loop will
45    /// call this method with the timeout's token
46    fn timeout(&mut self, token: Token, metrics: &mut SessionMetrics) -> StateResult;
47    /// cancel frontend timeout (and backend timeout if present)
48    fn cancel_timeouts(&mut self);
49    /// display the session's internal state (for debugging purpose),
50    /// ```plain
51    /// <context> Session(<State name>):
52    ///     Frontend:
53    ///         - Token(...) Readiness(...)
54    ///     Backends:
55    ///         - Token(...) Readiness(...)
56    ///         - Token(...) Readiness(...)
57    /// ```
58    fn print_state(&self, context: &str);
59    /// tell the session it has to shut down if possible
60    ///
61    /// if the session handles HTTP requests, it will not close until the response
62    /// is completely sent back to the client
63    fn shutting_down(&mut self) -> SessionIsToBeClosed {
64        true
65    }
66}