Module proxy 

mcpr-proxy

Full MCP proxy engine: per-request pipeline (intake → request chain → router → transport → response chain → emit), upstream forwarding, SSE streaming, widget CSP rewriting, per-proxy health. Embed this crate and wire a frontend (axum, warp, anything) around build_default_pipeline + pipeline::driver::Pipeline::run.

Module layout

proxy/
├── pipeline/       Per-request pipeline (parse → route → mw → emit)
├── proxy_state.rs  ProxyState — the runtime one proxy instance holds
├── forwarding.rs   UpstreamClient, forward_request, read_body_capped
├── sse.rs          SSE extract/wrap helpers
├── csp.rs          CspConfig, DirectivePolicy, WidgetScoped
├── rewrite.rs      RewriteConfig, rewrite_response (widget CSP)
└── health.rs       ProxyHealth, ConnectionStatus, SharedProxyHealth

Re-exports

pub use csp::CspConfig;

pub use csp::Directive;

pub use csp::DirectivePolicy;

pub use csp::Mode;

pub use csp::WidgetScoped;

pub use csp::effective_domains;

pub use csp::glob_match;

pub use health::ConnectionStatus;

pub use health::ProxyHealth;

pub use health::SharedProxyHealth;

pub use health::lock_health;

pub use health::new_shared_health;

pub use intake::from_axum_parts;

pub use pipeline_builder::ProxyPipeline;

pub use pipeline_builder::build_default_pipeline;

pub use proxy_state::ProxyState;

pub use rewrite::RewriteConfig;

pub use rewrite::rewrite_response;

pub use router::ProxyRouter;

pub use transport::ProxyTransport;

Modules

csp

CSP — Declarative Content Security Policy for widgets

emit

RequestEvent construction and emission.

forwarding

health

Per-proxy connection health and display state.

intake

Content-based classification of axum request parts into the Request sum type.

pipeline

Per-request proxy pipeline: a trait-driven middleware chain built on a small custom driver (see PIPELINE.md). The entrypoint is driver::Pipeline::run, constructed once at startup via crate::proxy::build_default_pipeline.

pipeline_builder

Default middleware chain construction for the pipeline.

proxy_state

ProxyState — everything one running proxy instance needs to serve traffic: upstream client, rewrite config, sessions, schema manager, per-proxy health, event bus handle. Request handlers take Arc<ProxyState>.

rewrite

Response rewriting for widget CSP

router

Pure (Request, Config) -> Route mapping. No I/O.

sse

transport

The single I/O layer for the pipeline.