Module backend_client 

Backend client handler that bridges server notifications to upstream peers.

Two isolation modes share one BackendNotificationBridge type so crate::proxy_handler::BackendRunningService stays a single concrete type:

• Shared (NotifyTarget::Shared): one backend, fan-out / progress·task routing via UpstreamPeerRegistry (stdio proxy).
• Per-session (NotifyTarget::Session): one backend connection owns one upstream Peer; notifications are 1:1 (URL proxy).

Structs

BackendNotificationBridge

Client-side handler used when the proxy connects to a backend MCP server.

ProgressRouteGuard

RAII guard that unregisters a progress route when dropped (after a short grace).

UpstreamPeerRegistry

Registry of upstream session peers that should receive backend notifications.

UpstreamPeerSlot

Slot for the single upstream peer in per-session isolation mode.

Enums

NotifyTarget

How backend notifications are delivered to upstream Streamable HTTP sessions.

Constants

PROGRESS_ROUTE_GRACE

Delay before unregistering a progress route after the owning request finishes.

Functions

default_backend_client_info

Default ClientInfo for proxy→backend handshake (enables task notifications).