I have a microservice in NestJs, here is the main.ts file:

async function bootstrap() {
  const app = await NestFactory.createMicroservice<MicroserviceOptions>(AppModule, {
    transport: Transport.REDIS,
    options: {
      url: 'redis://localhost:6379',
    }
  })
  await app.listen();
  console.log('Redis is running');
}
bootstrap();

I want to make calls to redis db from the service:

import { createClient } from '@redis/client';

async createWorkspaceShareCode(data: GetWorkspaceShareCodeMessage) {
    const client = createClient({
      url: 'redis://localhost:6379'
    });
    await client.connect();

    await client.set('key', 'value');
    const value = await client.get('key');
    return value;
  }

But that's not what I want, here are the issues:

• every time I make request, it creates new connection
• I need to write this code in each function to connect to redis (even though I'm already connected in main.ts file) Here is the question: how can I use some kind of RedisService in my NestJs microservice? I have already tried installing redis and nestjs-redis libraries, but the first one creates the issue described above and the second one just throws me an error: https://github.com/skunight/nestjs-redis/issues/97

CodePudding user response：

What I would do is keep your createMicroservice as you have it as it'll be encessary for a Redis based microservice server. Then you can create a module that exports a redis service like so:

@Module({
  providers: [
    {
      provide: 'REDIS_OPTIONS',
      useValue: {
        url: 'redis://localhost:6379'
      }
    },
    {
      inject: ['REDIS_OPTIONS']
      provide: 'REDIS_CLIENT',
      useFactory: async (options: { url: string }) => {
        const client = createClient(options);
        await client.connect();
        return client;
      }
    }
  ],
  exports: ['REDIS_CLIENT'],
})
export class RedisModule {}

Now in the module that contains the service you want to use add RedisModule to the imports array and in the service you can do @Inject('REDIS_CLIENT') private readonly redis: Redis to inject the redis instance and use it with this.redis.get('key') and this.redis.set('key', value)