@contractspec/lib.testing

Golden tests ensure new rollouts behave exactly like the traffic that inspired them. Record requests in production, replay them locally, and ship with confidence.

Installation

bun add @contractspec/lib.testing

Record traffic

import {
  TrafficRecorder,
  InMemoryTrafficStore,
} from '@contractspec/lib.testing/recorder';

const recorder = new TrafficRecorder({
  store: new InMemoryTrafficStore(),
  sampleRate: 0.02,
  sanitize: (snapshot) => ({
    ...snapshot,
    input: { ...snapshot.input, secret: undefined },
  }),
});

await recorder.record({
  operation: { name: 'orders.create', version: 6 },
  input: payload,
  output,
  success: true,
  tenantId: ctx.organizationId ?? undefined,
});

Generate suites

import { GoldenTestGenerator } from '@contractspec/lib.testing';

const generator = new GoldenTestGenerator();
const code = generator.generate(snapshots, {
  suiteName: 'orders.create golden path',
  runnerImport: './tests/run-operation',
  runnerFunction: 'runOrdersCommand',
  framework: 'vitest',
});

CLI workflow

contractspec test generate \
  --operation orders.create \
  --output tests/orders.create.golden.test.ts \
  --runner-import ./tests/run-operation \
  --runner-fn runOrdersCommand \
  --from-production \
  --days 7 \
  --sample-rate 0.05

Framework agnostic

Vitest by default, Jest via `generateJestSuite`, or call `runGoldenTests` manually inside CI.

Sanitize & sample

Scrub payloads before persistence and control sample rates per operation to stay within compliance limits.

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