Testing

Overview

@serviceconnect/core/testing is a subpath of the core package containing test helpers: an in-memory transport double so you can exercise a bus without a live broker, and shared contract suites that a new persistence backend runs against its store implementations to prove conformance. None of these helpers are included in the main @serviceconnect/core entry point — import them from the /testing subpath so they stay out of production bundles.

Import

import { fakeTransport, runSagaStoreContract } from '@serviceconnect/core/testing';
import type {
  FakeTransport,
  FakeTransportOptions,
  OutboxEntry,
} from '@serviceconnect/core/testing';

Transport doubles

export function fakeTransport(opts?: FakeTransportOptions): FakeTransport;
export function fakeProducer(opts?: FakeTransportOptions): ITransportProducer;
export function fakeConsumer(opts?: FakeTransportOptions): ITransportConsumer;

fakeTransport(opts?) — build an in-memory transport double for bus tests with no broker required. Returns { producer, consumer } plus an outbox array of OutboxEntry capturing everything that was published or sent. The returned object also exposes deliver(envelope) to feed an inbound message to the consumer, and cancelByBroker() / disconnect() / reconnect() to simulate connection state for health-check tests.
fakeProducer(opts?) — convenience accessor returning just the producer from a fresh fakeTransport.
fakeConsumer(opts?) — convenience accessor returning just the consumer from a fresh fakeTransport.

FakeTransportOptions lets you toggle transport capabilities the bus probes:

export interface FakeTransportOptions {
  readonly supportsRoutingKey?: boolean;   // default false
  readonly maxMessageSize?: number;        // default Number.POSITIVE_INFINITY
}

OutboxEntry

Each outbound operation appends one entry to transport.outbox:

export interface OutboxEntry {
  readonly operation: 'publish' | 'send' | 'sendBytes';
  readonly typeName: string;
  readonly endpoint?: string;
  readonly body: Uint8Array;
  readonly headers: Readonly<Record<string, string>>;
  readonly routingKey?: string;
  readonly routingSlipHopsCompleted?: number;
}

Assert against transport.outbox to verify what your handlers published or sent without round-tripping through a real broker.

Store contract suites

export function runSagaStoreContract(...): void;
export function runAggregatorStoreContract(...): void;
export function runTimeoutStoreContract(...): void;

Shared Vitest suites that a new persistence backend runs against its store implementations to prove conformance:

runSagaStoreContract — the conformance suite for an ISagaStore implementation (optimistic concurrency, load/save/delete semantics).
runAggregatorStoreContract — the conformance suite for an IAggregatorStore implementation (buffering, lease-based flush, timeout expiry).
runTimeoutStoreContract — the conformance suite for an ITimeoutStore implementation (scheduling and due-timeout dispatch).

Call the relevant suite from your backend’s test file, handing it a factory for your store, and it asserts the same behaviour the in-tree memory and MongoDB backends are held to.