TypeORM-Strict-Type

An all-TypeScript package which provides safer typing for functions in TypeORM.

• Enhansed type supports for TypeORM data-mapper pattern
  • Pick only joined relations with find*** functions.
• Almost zero runtime

Features

In TypeORM repositories, returned types of find*** functions have all relations, regardless of whether they are actually joined.

This package introduces type-safe repository type. Its find*** functions return only the actually joined relations by checking relations option.

This package is inspired by the article below:

TypeORMのData Mapperパターンにおけるリレーションの型安全性を担保する (Japanese)

Usage

1. Annotate relations with the Relation type in the entity.
2. Cast repository to the SafeRepository.
3. Just use the repository. The properties of returned types are automatically filtered.

@Entity()
class Sample {
  @OneToOne()
  rel: Relation<Sample2>; // 1. Annotate relation
}

const sampleRepository = dataSource.getRepository(
  Sample
) as unknown as SafeRepository<Sample>; // 2. Cast repository to the SafeRepository

// 3. Just use the repository. The properties of returned types are automatically filtered
const withoutRelations = await sampleRepository.find();
// => {}
const withRelations = await sampleRepository.find({
  relations: {
    rel: true,
  },
});
// => { rel: Relation<Sample2> }

For more information about usage, see the examples directory.

Installation

Available via npm.

npm i --save typeorm-strict-type

License

MIT