mcpr_core/proxy/pipeline/
middleware.rs

1//! Middleware traits for the pipeline.
2//!
3//! See `PIPELINE.md` §Middleware. `RequestMiddleware` inspects and may
4//! transform or short-circuit a `Request`; `ResponseMiddleware` mirrors
5//! the pattern on the way out.
6//!
7//! The driver that runs these traits lives in [`super::driver`].
8
9use async_trait::async_trait;
10
11use super::values::{Context, Request, Response};
12
13/// Decision a request middleware returns.
14#[derive(Debug)]
15pub enum Flow {
16    /// Forward the (possibly transformed) request to the next
17    /// middleware.
18    Continue(Request),
19    /// Produce a response directly. Later request middlewares and the
20    /// router/transport do not run, but the full response chain still
21    /// processes the response.
22    ShortCircuit(Response),
23}
24
25#[async_trait]
26pub trait RequestMiddleware: Send + Sync {
27    /// Stable identifier used for `info!` registration logs and test
28    /// introspection. Return a `&'static str` literal.
29    fn name(&self) -> &'static str;
30
31    /// Inspect or transform the request. Variants the middleware does
32    /// not care about return `Flow::Continue(req)` unchanged.
33    async fn on_request(&self, req: Request, cx: &mut Context) -> Flow;
34}
35
36#[async_trait]
37pub trait ResponseMiddleware: Send + Sync {
38    fn name(&self) -> &'static str;
39
40    /// Inspect or transform the response. Always returns a `Response`
41    /// — replacing one variant with another is how a middleware swaps
42    /// the result.
43    async fn on_response(&self, resp: Response, cx: &mut Context) -> Response;
44}
mcpr_core/proxy/pipeline/middleware.rs

mcpr_core/proxy/pipeline/
middleware.rs
