Adding an ElasticSearch connection to app.module on Nestjs

Question

I'm trying to create a connection with ElasticSearch on my app.module.ts. My project folder looks like:

src
 |database
   |- elasticsearch-database.module.ts
   |- es.services.ts
 |services
   |- products
      |-products.controller.ts
      |-products.module.ts
      |-products.service.ts
 app.module.ts

First, I'm creating the connection on elasticsearch-database.module.ts

 @Global()
    @Module({
        imports: [
            ElasticsearchModule.registerAsync({
                useFactory: () => ({
                  node: 'http://localhost:9200'
                })
              })
        ],
        providers: [SearchService],
        exports: [SearchService]
    })

export class elasticSearchDatabaseModule{}

My SearchService is on es.services.ts

@Injectable()
export class SearchService {
  constructor(private readonly elasticsearchService: ElasticsearchService) {}
}

Then, I'm importing elasticSearchDatabaseModule on

app.module.ts

@Module({
  imports: [
    elasticSearchDatabaseModule,
    ProductsModule
  ],
  
})
export class AppModule {}

My ProductsModule on products.module.ts

@Module({
    imports: [
        elasticSearchDatabaseModule,

    ],
    controllers: [ProductsController],
    providers: [ ProductsService],
})

export class EventsModule { }

And finally, on ProductsService , I have

import { ElasticsearchService } from "@nestjs/elasticsearch";
@Injectable()
export class EventsService {
    constructor(
        private readonly elasticSearch      : ElasticsearchService
    ) { }
}

The error occuring is:

Potential solutions:
- If ElasticsearchService is a provider, is it part of the current EventsModule?
- If ElasticsearchService is exported from a separate @Module, is that module imported within EventsModule?
  @Module({
    imports: [ /* the Module containing ElasticsearchService */ ]
  })
 +3ms
Error: Nest can't resolve dependencies of the EventsService (?). Please make sure that the argument ElasticsearchService at index [0] is available in the EventsModule context.

I am able to fully compile without error if I create the connection directly on products.module.ts:

imports: [
     
        ElasticsearchModule.register({
            node: 'http://elasticsearch:9200',
        })
    ]

But I think it's not the best approach if I want to use that elasticSearch connection in other services.

score 1 · Accepted Answer · answered Apr 01 '22 at 03:42

1

If you want to expose all the providers exported by that dynamic module (ElasticsearchModule.registerAsync() one), you'll need to export ElasticsearchModule module. See: https://docs.nestjs.com/modules#module-re-exporting

To do so, just add ElasticsearchModule to the exports array of elasticSearchDatabaseModule module.

answered Apr 01 '22 at 03:42

Micael Levi

5,054
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That worked perfectly, I thought that simply importing elasticSearchDatabaseModule would do the trick, thanks! – PedroSG Apr 01 '22 at 13:06
1

you can think like this: the "public API" of a nestjs module is defined by the `exports` array. Thus, the `elasticSearchDatabaseModule` that you've have before was just exposing the provider `SearchService` – Micael Levi Apr 01 '22 at 14:33

Adding an ElasticSearch connection to app.module on Nestjs

1 Answers1