Building Reusable DTO Components in NestJS with @nestjs/mapped-types

In modern web development, Data Transfer Objects (DTOs) play a critical role in ensuring that data is correctly validated, transformed, and communicated between different layers of an application. In NestJS, DTOs help manage data flow, especially between controllers and services, by defining how data is structured for API interactions.

However, as your application grows, managing DTOs can become cumbersome, especially when you need to create different versions of DTOs for various operations like Create, Update, and Response. Fortunately, @nestjs/mapped-types simplifies this process by allowing you to build reusable DTO components, reducing redundancy and improving maintainability.

In this blog post, we’ll explore how to build reusable DTO components in NestJS using @nestjs/mapped-types.

What is @nestjs/mapped-types?

@nestjs/mapped-types is a utility package designed to help you reuse and manipulate DTOs more efficiently. It provides a set of helper functions such as PartialType, PickType, and OmitType, allowing you to create variations of DTOs without rewriting the same fields multiple times.

These utilities are especially useful for creating different DTOs for creating, updating, and retrieving resources…