NestJS Enterprise

NestJS enterprise is a collection of tools and utilities to help you build enterprise-grade applications with NestJS.

Installation

Add @rnw-community/nestjs-enterprise to your project using you package manager of choice.

Peer dependencies that your project should contain:

• @nestjs/common ^11.1.28,
• RxJS ^7.8.2

Some features have additional installation requirements, please refer to the feature documentation for more information.

Contents

Decorators

• Log - method call logging
• Histogram Metric - Prometheus histogram metrics

Distributed Locking

Create lock decorators bound to any injectable LockServiceInterface via NestJS DI:

const { SequentialLock, ExclusiveLock } = createPromiseLockDecorators(MyLockService, 5000);
const { SequentialLock$, ExclusiveLock$ } = createObservableLockDecorators(MyLockService, 5000);

• createPromiseLockDecorators - SequentialLock + ExclusiveLock for async methods
• createObservableLockDecorators - SequentialLock$ + ExclusiveLock$ for Observable methods

Types

• PreDecoratorFunction<TArgs, TResult> - (...args: TArgs) => TResult; the spread-form callback shape accepted as the preLock argument to SequentialLock/ExclusiveLock/SequentialLock$/ExclusiveLock$ (and the deprecated LockPromise/LockObservable) — computes the lock resource key(s) from the decorated method's own arguments.

  import type { PreDecoratorFunction } from '@rnw-community/nestjs-enterprise';
  
  const preLock: PreDecoratorFunction<[orderId: string], string[]> = orderId => [`order:${orderId}`];

• LockServiceInterface - the contract createPromiseLockDecorators / createObservableLockDecorators expect from an injectable NestJS provider: acquire(resources, duration) resolves a LockHandle; tryAcquire(resources, duration) resolves LockHandle | undefined, returning undefined on contention instead of waiting or throwing.

  import type { LockServiceInterface } from '@rnw-community/nestjs-enterprise';
  
  class RedlockService implements LockServiceInterface {
      async acquire(resources: string[], duration: number) {
          return { release: async () => undefined };
      }
      async tryAcquire(resources: string[], duration: number) {
          return { release: async () => undefined };
      }
  }

• LockHandle - { release(): Promise<void> }; returned by LockServiceInterface.acquire / tryAcquire and released automatically once the decorated method settles.

  import type { LockHandle } from '@rnw-community/nestjs-enterprise';
  
  const handle: LockHandle = { release: async () => undefined };

Deprecated

• LockPromise - use createPromiseLockDecorators instead
• LockObservable - use createObservableLockDecorators instead
• LockableService - use LockServiceInterface instead

License

This library is licensed under The MIT License.