How do you make a DataLoader available in the GraphQL context so every resolver can access it in NestJS?

Q: How do you make a DataLoader available in the GraphQL context so every resolver can access it in NestJS?

// Attach to context in module config — called per request GraphQLModule.forRootAsync ({ driver: ApolloDriver, imports: [PostsModule], useFactory: (postsLoader: PostsDataLoader) => ({ autoSchemaFile: true, context: () => ({ postsLoader: postsLoader.batchLoadPosts, // fresh per request }), }), inject: [PostsDataLoader], }) // Type-safe context interface export interface GqlContext { req: Request; postsLoader: DataLoader ; } // Access in any resolver via @Context() @ResolveField(() => [Post]) posts( @Parent() user: User, @Context() ctx: GqlContext, ): Promise { return ctx.postsLoader.load(user.id); } Context factory is called per request — each request gets its own DataLoader instance automatically. Avoids injecting the loader service into every resolver that needs it. A single GqlContext interface documents all available loaders in one place. Resolvers stay clean — access loaders via @Context() without constructor injection overhead. Multiple loaders for different entities can all be attached to the same context object.

Difficulty: 6/10

GraphQL context, DataLoader integration, NestJS providers

Attach DataLoader instances to the GraphQL context in the GraphQLModule.forRootAsync() context factory. The factory is called per request, so each request gets a fresh loader. Resolvers access the loader via the @Context() decorator instead of injecting the loader service directly into every resolver class.

DataLoader in GraphQL context

Context-based DataLoader benefits:

1
Context factory is called per request — each request gets its own DataLoader instance automatically.
2
Avoids injecting the loader service into every resolver that needs it.
3

How do you make a DataLoader available in the GraphQL context so every resolver can access it in NestJS?

Difficulty: 6/10

GraphQL context, DataLoader integration, NestJS providers

Attach DataLoader instances to the GraphQL context in the GraphQLModule.forRootAsync() context factory. The factory is called per request, so each request gets a fresh loader. Resolvers access the loader via the @Context() decorator instead of injecting the loader service directly into every resolver class.

DataLoader in GraphQL context

Context-based DataLoader benefits:

1
Context factory is called per request — each request gets its own DataLoader instance automatically.
2
Avoids injecting the loader service into every resolver that needs it.
3

How do you make a DataLoader available in the GraphQL context so every resolver can access it in NestJS?

How do you make a DataLoader available in the GraphQL context so every resolver can access it in NestJS?

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