Using Service Container¶

Overview¶

Validator supports service container integration when you want to inject dependencies into your custom validator constraint classes.

Integration with TypeDI¶

Here is an example of how to integrate it with TypeDI:

import { Container } from 'typedi';
import { useContainer, Validator } from 'class-validator';

// do this somewhere in the global application level:
useContainer(Container);
let validator = Container.get(Validator);

// now everywhere you can inject Validator class which will go from the container
// also you can inject classes using constructor injection into your custom ValidatorConstraint-s

Example with Dependencies¶

import { ValidatorConstraint, ValidatorConstraintInterface } from 'class-validator';
import { UserRepository } from './UserRepository';

@ValidatorConstraint({ async: true })
export class IsUserAlreadyExistConstraint implements ValidatorConstraintInterface {
    constructor(protected userRepository: UserRepository) {}

    validate(userName: string) {
        return this.userRepository.findOneByName(userName).then(user => {
            if (user) return false;
            return true;
        });
    }
}