`@Optional()`

Marks an injected dependency as optional so resolution does not fail when absent.

Since NestJS 10/11 Spec ↗

Syntax

@Optional()

Returns

ParameterDecorator — A decorator applied to a constructor parameter.

Examples

import { Injectable, Optional, Inject } from '@nestjs/common';

@Injectable()
export class HttpService {
  constructor(
    @Optional() @Inject('HTTP_OPTIONS') private options?: { timeout: number },
  ) {
    this.options ??= { timeout: 5000 };
  }
}

Notes

Without @Optional(), Nest throws if a dependency cannot be resolved. With it, the parameter receives undefined so you can supply sensible defaults.