Function proxy_to_backend_streaming

crates/openshell-router/src/backend.rs:728–746

Forward a raw HTTP request to the backend, returning response headers immediately without buffering the body. The caller streams the body incrementally via [`StreamingProxyResponse::response`] using `chunk().await`.

(
    client: &reqwest::Client,
    route: &ResolvedRoute,
    _source_protocol: &str,
    method: &str,
    path: &str,
    headers: Vec<(String, String)>,
    body: bytes::Bytes,
)

/// The caller streams the body incrementally via
/// [`StreamingProxyResponse::response`] using `chunk().await`.
pub async fn proxy_to_backend_streaming(
    client: &reqwest::Client,
    route: &ResolvedRoute,
    _source_protocol: &str,
    method: &str,
    path: &str,
    headers: Vec<(String, String)>,
    body: bytes::Bytes,
) -> Result<StreamingProxyResponse, RouterError> {
    let response =
        send_backend_request_streaming(client, route, method, path, &headers, body).await?;
    let (status, resp_headers) = extract_response_metadata(&response);

    Ok(StreamingProxyResponse {
        status,
        headers: resp_headers,
        body: StreamingBody::Live(response),
    })
}

/// Build the upstream URL for a provider route.
///