ObservationHub

import type { ObservationHub } from "@elie-laloum/outpost";

Parameters and properties

scopeRequired
ObservationScope
Immutable correlation fields inherited by emissions from this hub.
errorsRequired
readonly unknown[]
Shared bounded collection of sink, serialization, overflow and timeout errors; retains the first 100 failures independently of execution.
droppedRequired
number
Shared count of delivery losses across sinks, including overflow and disabled receivers.
verboseRequired
boolean
Whether producers may emit full model request and response payloads; journal retention is configured separately.
emitRequired
(source: ObservationSource, event: ObservationEvent) => void
Stamps an event with seq, timestamp, source and this hub’s scope, then delivers a copy to inherited and local sinks. Does nothing after close(); sink failures go to errors, never thrown.
childRequired
(scope: ObservationScope, sinks?: readonly ObservationSink[]) => ObservationHub
Create a scoped child sharing sequence and delivery diagnostics, optionally adding sinks only for that child and its descendants.
flushRequired
() => Promise<void>
Drain the current delivery snapshot and flush registered sinks with bounded waits; later emissions belong to a later snapshot.
closeRequired
() => Promise<void>
Stop emissions from this child and its descendants, drain its delivery snapshot and detach its own sinks without closing caller-owned parent sinks.

Signature

export interface ObservationHub {
  readonly scope: ObservationScope;
  readonly errors: readonly unknown[];
  readonly dropped: number;
  readonly verbose: boolean;
  emit(source: ObservationSource, event: ObservationEvent): void;
  child(
    scope: ObservationScope,
    sinks?: readonly ObservationSink[],
  ): ObservationHub;
  flush(): Promise<void>;
  close(): Promise<void>;
}

Parameters and properties

Signature

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