Crate cloudflare_quick_tunnel 

cloudflare-quick-tunnel — pure-Rust client for Cloudflare’s https://*.trycloudflare.com “quick tunnel” service.

Drop-in replacement for the common pattern of spawning the cloudflared Go binary as a subprocess and scraping its stderr for the public URL. Speaks QUIC + Cap’n Proto-RPC to the argotunnel edge natively, so the host application stays a single self-contained Rust binary.

See docs/spike-verdict.md for the design decision record and the three undocumented edge gotchas (ALPN / SNI / trust roots) that the spike crate proved out against the production edge.

Re-exports

pub use error::TunnelError;

pub use manager::QuickTunnelHandle;

pub use manager::QuickTunnelManager;

pub use manager::TunnelMetrics;

Modules

api

POST /tunnel client for api.trycloudflare.com.

edge

Cloudflare edge discovery: DNS SRV (_v2-origintunneld._tcp.argotunnel.com) with a DNS-over-TLS fallback through 1.1.1.1:853. Mirrors the semantics of cloudflared/edgediscovery/allregions/discovery.go.

error

Typed error model for the quick-tunnel client. Each variant corresponds to a distinct failure mode that callers can act on independently (API rejection vs DNS gap vs handshake refused vs permanent supervisor giveup).

manager

Top-level orchestrator. QuickTunnelManager::start() runs:

pool

Bounded idle-TCP-connection pool against 127.0.0.1:<port>.

proxy

Per-request HTTP/1.1 proxy: bridge an inbound capnp-framed stream from the edge to the local TCP listener the caller wants to expose at https://<sub>.trycloudflare.com.

quic_dial

QUIC dial into the argotunnel edge using stock quinn + rustls. The handshake recipe was nailed down in the design spike (see docs/spike-verdict.md):

quic_metadata_protocol_capnp

rpc

Cap’n Proto-RPC client for the TunnelServer / RegistrationServer interface (see schemas/tunnelrpc.capnp).

stream

Per-request stream framing on the edge ↔ tunnel side.

supervisor

Long-running task that owns one QUIC connection after register.

tunnelrpc_capnp