Required

@tsed/schema

Usage

import { Required } from "@tsed/schema";

See /packages/specs/schema/src/decorators/common/required.ts.

Overview

const Required: import("../../utils/withErrorMsg.js").ErrorChainedDecorator<(required?: boolean, ...allowedRequiredValues: any[]) => any>;

Description

Mark a property or parameter as required.

The @Required() decorator enforces that a property must have a value during validation. It works on both model properties and method parameters, and triggers validation errors when values are null, undefined, or empty strings.

Usage on Properties

class User {
  @Required()
  @Property()
  email: string;

  @Required()
  @Property()
  name: string;
}

Usage on Parameters

@Controller("/users")
class UserController {
  @Post("/")
  async create(@Required() @BodyParams() user: User) {
    // user is required in request body
  }

  @Get("/:id")
  async get(@Required() @PathParams("id") id: string) {
    // id is required in path
  }
}

Validation Behavior

By default, @Required() rejects:

• null values
• undefined values
• Empty strings ("")

Allowing Specific Values

Use @Allow() to permit specific values that would normally be rejected:

class Model {
  // Allow empty string but still mark as required
  @Required()
  @Allow("")
  optionalText: string;

  // Allow null
  @Required()
  @Allow(null)
  nullableField: string | null;
}

Making Optional

To explicitly mark a property as optional:

class Model {
  @Required(false) // or use @Optional()
  optionalField: string;
}