Struct ForwarderClient 

pub struct ForwarderClient { /* private fields */ }

Forwarder client for sending requests to upstream backends.

Implementations

impl ForwarderClient

pub fn new(timeout: Duration) -> Self

Create a new forwarder client.

pub async fn forward( &self, backend: &Backend, request: Request<BoxBody<Bytes, Error>>, ) -> Result<Response<Incoming>, ProxyError>

Forward a request to a backend.

pub async fn forward_upgrade( &self, backend: &Backend, request: Request<BoxBody<Bytes, Error>>, tunnel_idle: Duration, ) -> Result<Response<BoxBody<Bytes, Error>>, ProxyError>

Forward a protocol-upgrade request (WebSocket) and tunnel the result.

This cannot use the pooled client: once the upstream answers 101 the connection stops being request/response and becomes an opaque byte stream, which a connection pool has no way to hand back. So dial the backend directly, keep the lower-level connection, and splice the two upgraded halves together.

HTTP/1.1 only; Self::forward_h2_websocket is the HTTP/2 spelling.

Which protocols may be upgraded to is the caller’s decision, made before this is called: this tunnels whatever Upgrade the request carries. The tunnel is closed after tunnel_idle with no bytes in either direction.

pub async fn forward_h2_websocket( &self, backend: &Backend, request: Request<BoxBody<Bytes, Error>>, protocol: &str, tunnel_idle: Duration, ) -> Result<Response<BoxBody<Bytes, Error>>, ProxyError>

Forward an HTTP/2 extended CONNECT (RFC 8441) to an HTTP/1.1 WebSocket origin, translating between the two handshakes.

The two are not the same conversation, so this is a rewrite rather than a relay:

• HTTP/2 carries the intent in :method = CONNECT and :protocol; HTTP/1.1 carries it in Upgrade plus a Connection token.
• HTTP/2 has no Sec-WebSocket-Key. The nonce exists to stop an HTTP/1.1 cache from mistaking the handshake for an ordinary response, which does not apply to a multiplexed stream. The h1 origin still requires one, so the proxy generates it here.
• Success is 101 on the wire to the origin but 200 back to the client; a 101 has no meaning on an HTTP/2 stream.

The origin’s Sec-WebSocket-Accept is not verified against the generated key. Status 101 plus a websocket Upgrade is taken as sufficient, which avoids a SHA-1 dependency for a check that guards against a misconfigured origin rather than an attacker.

As with Self::forward_upgrade, whether protocol is allowed is for the caller to decide first.

Trait Implementations

impl Default for ForwarderClient

fn default() -> Self

Returns the “default value” for a type.