Enum Backend 

pub enum Backend {
    InProcess(Routes),
    Upstream(Channel),
}

Where a translated gRPC request is dispatched.

Variants

InProcess(Routes)

In-process: call the local tonic Routes (wrap a service you own).

Upstream(Channel)

Upstream: forward to a remote gRPC server over an HTTP/2 Channel (proxy mode).

Implementations

impl Backend

pub async fn call( &self, req: Request<TonicBody>, ) -> Result<Response<ResBody>, BoxError>

Dispatch a gRPC-framed HTTP request and return the HTTP response. The two backends’ response bodies differ in type; both are boxed into one ResBody here, so every caller downstream is monomorphic. InProcess is infallible (its Service::Error is Infallible); Upstream surfaces the transport error for the caller to map to a gRPC status (UNAVAILABLE / BAD_GATEWAY).

pub fn is_upstream(&self) -> bool

Whether this backend forwards to a remote upstream (proxy mode). Used to pick policies that only make sense across the network — enforcing the client deadline locally, forwarding grpc-timeout with grace, capping concurrent streams.

Trait Implementations

impl Clone for Backend

fn clone(&self) -> Backend

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.