@edirect/lock

The EDirectInsure Distributed Lock module.

@edirect/lock

Distributed lock module for Edirect applications. Provides cluster-safe locking mechanisms using Redis, supporting both timed and distributed locks for critical section management.

Features

• Distributed locking using Redis
• Timed locks for exclusive task execution
• Integrates with NestJS and Edirect config modules

Installation

npm install @edirect/lock

Usage

Import and register LockModule in your AppModule:

import { ConfigService } from '@edirect/config';

@Module({
  imports: [
    LockModule.registerAsync({
      imports: [ConfigModule],
      useFactory: async (configService: ConfigService) => ({
        lockOwner: configService.get(Variables.NAMESPACE),
        redis: {
          host: configService.get(Variables.REDIS_HOST),
          password: configService.get(Variables.REDIS_PASS),
          port: +configService.get(Variables.REDIS_PORT),
        },
      }),
      inject: [ConfigService],
    }),
  ],
})
export class AppModule {}

API

Timed Lock

lock(key: string, callback: (unlock: () => void) => void, ttl?: number): void

Redis Values

set(key: string, value: string, override = false): Promise<void>
get(key: string): Promise<string>
/**

Distributed Lock

getLockOwner(): Promise<string>
setLockOwner(): Promise<string>
removeLockOwner(): Promise<void>
isLockOwner(): Promise<boolean>

For example, the usage of the Distributed Lock:

if (await this.lockService.isLockOwner()) {
  // Logic that should run on only one cluster
}

And for the Timed Lock:

this.lockService.lock('locked-task-name', async unlock => {
  // Logic that should be executed in exclusivity, across all instances

  unlock();
});

Environment Variables

• REDIS_HOST: Redis server host
• REDIS_PORT: Redis server port
• REDIS_PASS: Redis password (if required)
• NAMESPACE: Lock owner namespace