Validate Request with a Pipe
Discover how to implement ValidationPipe in NestJS to automate request validation using decorators from class-validator. Learn to enforce data integrity, handle errors gracefully, strip unwanted properties, and manage validation on route parameters to build robust RESTful APIs.
The ValidationPipe pipe
In this lesson, we’ll delve into setting up and implementing autovalidation with ValidationPipe. We’ll also explore how to use ValidationPipe for error handling and removing redundant properties to enhance the robustness of our application.
Installation
Although ValidationPipe is provided as part of the NestJS framework, we still need to install additional dependencies to use specific features. The ValidationPipe pipe relies on the class-validator and class-transformer packages to perform autovalidation. We must install these two dependencies using the command given below:
$ npm i --save class-validator class-transformer
The class-validator package provides decorators and validation functions to define the constraints for the data while the class-transformer package helps with data transformation to ensure the data matches the defined structure.
Configure autovalidation
Autovalidation means we don’t need to write code to validate incoming requests. Instead, we use decorators from the class-validator package to specify validation constraints in DTOs. Then, we apply ValidationPipe to enforce the validation rules defined automatically. ...