Add Fake (in-memory) adapter

[icebob]

Summary

Adds a new Fake (in-memory) adapter that covers the same functionality as the Redis adapter, but stores jobs only in process memory. It is intended for testing & development, so no Redis server is needed. (The README feature list already advertised it, and the commented-out placeholders in adapters/index.ts and the unit tests are now live.)

Implementation

• src/adapters/fake.ts — FakeAdapter extends BaseAdapter + a FakeStorage engine that mimics the Redis data structures (hash, list, set, sorted set, string with lazy expiration).
  • The storage is a static registry keyed by prefix, so all adapter instances (workers + middleware clients, even across multiple brokers in one process) share data — the same way tests communicate through a common Redis server. FakeAdapter.clearAll() is available for tests; data survives disconnect() like Redis data does.
  • Pub/Sub is replaced by an EventEmitter (signals, finished, delayed promoteAt channels).
  • The blocking BRPOPLPUSH is replaced by a FIFO waiter queue: each pushed job wakes exactly one blocked worker (like Redis serves blocked clients), keeping drainDelay semantics.
  • Job data round-trips through the Moleculer serializer (like Redis), so payload mutation / non-serializable bugs surface in tests too.
• Refactor: serializeJob, deserializeJob, getBackoffTime and formatZrangeResultToObject moved from RedisAdapter to BaseAdapter (shared with the new adapter).
• Tests:
  • New test/unit/fake.spec.ts (39 tests: key scheme parity, shared/isolated storages, storage command semantics, lazy lock/signal expiration, popWaitingJob wake/timeout).
  • The whole integration suite is parametrized over the adapter: WF_TEST_ADAPTER=Fake npm run test:integration (or the new test:integration:fake script) runs all 78 integration tests without Redis (the multi-broker specs switch to the Fake transporter as well).
  • CI matrix now runs the suite with both Redis and Fake adapters.
• Docs: README ### Fake adapter section with usage examples, options table and a 'not for production' warning; CHANGELOG entry.

Intentional behavioral differences vs. Redis adapter

In-memory execution makes some races deterministic that network latency hides on Redis:

• If a job is removed (broker.wf.remove) while it is being processed, the Fake adapter does not re-create the job hash when persisting startedAt/result/error, so the job stays removed.
• The no-arg cleanUp() really deletes everything with the prefix. Note: the Redis adapter has a bug here — it scans this.prefix + ":*", but the prefix already ends with :, so the pattern never matches. Worth a separate fix.
• The multi-worker distribution assertion in batch.spec.ts uses a lower floor for Fake (850 vs 980) — single-threaded scheduling is slightly less even.

Other notes

• Replicated as-is for parity (possible upstream bug): lock() throws a plain WorkflowError, while processJob catches WorkflowAlreadyLocked, so that catch branch never triggers.
• Fixed pre-existing issues in adapters.spec.ts (unawaited cleanup()/broker.stop(), cleanup used the wrong workflow name adapters.simple).
• Added the missing globals devDependency (imported by eslint.config.mjs but not declared — lint could not run without it).

Test plan

• npm run check + npm run lint clean (only pre-existing warnings)
• npm run test:unit — 58 passed
• WF_TEST_ADAPTER=Fake integration suite — 78/78 passed, no Redis needed
• Redis integration suite — passed (the occasional single flaky failure under full parallel load exists on master too and passes standalone)

🤖 Generated with Claude Code

[Copilot]

Pull request overview

This PR adds a new Fake (in-memory) adapter to the Moleculer workflows middleware, intended to enable local development and testing without requiring a Redis server, while keeping behavior largely aligned with the existing Redis adapter.

Changes:

• Introduces FakeAdapter + FakeStorage to emulate Redis-like data structures and Pub/Sub semantics in-process.
• Refactors shared adapter logic by moving serializeJob, deserializeJob, getBackoffTime, and formatZrangeResultToObject into BaseAdapter.
• Parameterizes integration tests and CI to run the suite against both Redis and Fake adapters via WF_TEST_ADAPTER.

Reviewed changes

Copilot reviewed 25 out of 26 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
test/utils.js	Adds adapterType/transporterType helpers driven by WF_TEST_ADAPTER.
test/unit/index.spec.ts	Enables Fake adapter resolver tests and adds class-based resolution coverage.
test/unit/fake.spec.ts	Adds unit tests for FakeAdapter keying, shared storage, storage semantics, and waiter wake/timeout behavior.
test/integration/timeout.spec.ts	Uses adapterType instead of hard-coded "Redis".
test/integration/stalled.spec.ts	Uses adapterType instead of hard-coded "Redis".
test/integration/signal.spec.ts	Uses adapterType instead of hard-coded "Redis".
test/integration/serialization.spec.ts	Uses adapterType in adapter config object.
test/integration/retries.spec.ts	Uses adapterType instead of hard-coded "Redis".
test/integration/retention.spec.ts	Uses adapterType instead of hard-coded "Redis".
test/integration/repeat.spec.ts	Uses adapterType and relaxes a timestamp assertion for adapter parity.
test/integration/middleware.spec.ts	Uses adapterType for both broker and worker.
test/integration/index.spec.ts	Uses adapterType and transporterType for multi-broker tests.
test/integration/events.spec.ts	Uses adapterType/transporterType and adds delays to allow async event delivery.
test/integration/delayed.spec.ts	Uses adapterType instead of hard-coded "Redis".
test/integration/collision.spec.ts	Uses adapterType instead of hard-coded "Redis".
test/integration/batch.spec.ts	Uses adapterType and adjusts distribution floor for Fake adapter behavior.
test/integration/adapters.spec.ts	Skips Redis-only cases under Fake and adds Fake adapter coverage; fixes cleanup awaiting.
src/adapters/redis.ts	Removes now-shared helper methods (moved into BaseAdapter); minor typing tweak for serializer.
src/adapters/index.ts	Registers Fake adapter and extends resolver to accept adapter classes.
src/adapters/fake.ts	Adds the new in-memory adapter implementation.
src/adapters/base.ts	Adds shared job (de)serialization, backoff computation, and zrange formatting utilities.
README.md	Documents Fake adapter usage and options with a non-production warning.
package.json	Adds test:integration:fake script and dev dependencies (cross-env, globals).
package-lock.json	Locks new dev dependencies.
CHANGELOG.md	Adds Unreleased entry describing Fake adapter and shared-method refactor.
.github/workflows/test.yml	Runs CI matrix for both adapters; skips Redis containers for Fake runs.