How do you implement cursor-based pagination in NestJS GraphQL using the Relay Connection spec?

Q: How do you implement cursor-based pagination in NestJS GraphQL using the Relay Connection spec?

@ObjectType() export class PageInfo { @Field() hasNextPage: boolean; @Field() hasPreviousPage: boolean; @Field({ nullable: true }) startCursor?: string; @Field({ nullable: true }) endCursor?: string; } @ObjectType() export class UserEdge { @Field(() => User) node: User; @Field() cursor: string; } @ObjectType() export class UserConnection { @Field(() => [UserEdge]) edges: UserEdge[]; @Field(() => PageInfo) pageInfo: PageInfo; @Field(() => Int) totalCount: number; } @Query(() => UserConnection) async users( @Args('first', { type: () => Int, nullable: true }) first?: number, @Args('after', { nullable: true }) after?: string, ): Promise { const limit = first ?? 10; const cursor = after ? Buffer.from(after, 'base64').toString() : undefined; const [users, total] = await this.usersService.findPage(limit + 1, cursor); const hasMore = users.length > limit; const nodes = hasMore ? users.slice(0, -1) : users; const edges = nodes.map(u => ({ node: u, cursor: Buffer.from(String(u.id)).toString('base64'), })); return { edges, totalCount: total, pageInfo: { hasNextPage: hasMore, hasPreviousPage: !!after, startCursor: edges[0]?.cursor, endCursor: edges.at(-1)?.cursor, }, }; } Fetch limit + 1 records to determine hasNextPage without a separate COUNT query. Encode cursors as base64 opaque strings — clients should not parse or construct them. The cursor typically encodes the last seen ID or a sort key for stable ordering. Use after/before for forward/backward navigation; first/last for page size. Return totalCount so clients can show pagination progress without knowing the full dataset.

Difficulty: 6/10

cursor pagination, Relay Connection spec, NestJS GraphQL

Create Connection, Edge, and PageInfo ObjectTypes following the Relay spec. The query accepts first and after arguments. Fetch one extra record beyond the limit to determine hasNextPage. Encode cursors as base64 strings. Return edges with node and cursor fields alongside pageInfo with navigation metadata.

Relay-style cursor pagination types and resolver

Cursor pagination design rules:

1
Fetch limit + 1 records to determine hasNextPage without a separate COUNT query.

How do you implement cursor-based pagination in NestJS GraphQL using the Relay Connection spec?

Difficulty: 6/10

cursor pagination, Relay Connection spec, NestJS GraphQL

Create Connection, Edge, and PageInfo ObjectTypes following the Relay spec. The query accepts first and after arguments. Fetch one extra record beyond the limit to determine hasNextPage. Encode cursors as base64 strings. Return edges with node and cursor fields alongside pageInfo with navigation metadata.

Relay-style cursor pagination types and resolver

Cursor pagination design rules:

1
Fetch limit + 1 records to determine hasNextPage without a separate COUNT query.

How do you implement cursor-based pagination in NestJS GraphQL using the Relay Connection spec?

How do you implement cursor-based pagination in NestJS GraphQL using the Relay Connection spec?

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