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OutboundInterceptor

dactor::interceptor

Trait OutboundInterceptor 

Source 
pub trait OutboundInterceptor:
    Send
    + Sync
    + 'static {
    // Required method
    fn name(&self) -> &'static str;

    // Provided methods
    fn on_send(
        &self,
        ctx: &OutboundContext<'_>,
        runtime_headers: &RuntimeHeaders,
        headers: &mut Headers,
        message: &dyn Any,
    ) -> Disposition { ... }
    fn on_reply(
        &self,
        ctx: &OutboundContext<'_>,
        runtime_headers: &RuntimeHeaders,
        headers: &Headers,
        outcome: &Outcome<'_>,
    ) { ... }
    fn on_expand_item(
        &self,
        ctx: &OutboundContext<'_>,
        headers: &Headers,
        seq: u64,
        item: &dyn Any,
    ) -> Disposition { ... }
}
Expand description

An outbound interceptor that runs on the SENDER side before the message is delivered to the target actor’s mailbox.

Use cases: tracing context propagation, rate limiting, circuit breaking, header stamping, metrics, logging.

Required Methods§

Source

fn name(&self) -> &'static str

Human-readable name.

Provided Methods§

Source

fn on_send( &self, ctx: &OutboundContext<'_>, runtime_headers: &RuntimeHeaders, headers: &mut Headers, message: &dyn Any, ) -> Disposition

Called before the message is sent. Can modify headers, delay, reject, or retry. The message body is provided as &dyn Any for inspection.

Source

fn on_reply( &self, ctx: &OutboundContext<'_>, runtime_headers: &RuntimeHeaders, headers: &Headers, outcome: &Outcome<'_>, )

Called when an ask() reply is received back on the sender side. The reply is type-erased — downcast if you know the type.

Note: Not yet wired in TestRuntime — will be connected when the reply path flows through the outbound pipeline (future PR).

Source

fn on_expand_item( &self, ctx: &OutboundContext<'_>, headers: &Headers, seq: u64, item: &dyn Any, ) -> Disposition

Called for each item flowing through a stream or feed on the sender side.

  • Stream (server-streaming): called when each reply item arrives back at the caller.
  • Feed (client-streaming): called when each input item is about to be sent to the target actor.

seq is a zero-based sequence number within this stream/feed. The item is type-erased; downcast if you know the concrete type.

Returns Disposition to control per-item flow:

  • Continue — deliver/forward the item normally.
  • Drop — silently skip this item.
  • Delay(d) — pause for d before forwarding (backpressure).
  • Reject(reason) — terminate the stream with an error.
  • Retry(d) — not meaningful for stream items; treated as Drop.

Implementors§