Nestjs IsEnum dto validation and swagger

Question

This is working fine:

    import { IsIn } from 'class-validator';
    import { ApiProperty } from '@nestjs/swagger';

    export class createEventDto {
      @IsIn([0, 1, 2, 3, 4, 5])
      @ApiProperty({
        description: 'description of the severity property',
      })
      severity: number;
    }

and looks like this in swagger:

I am trying to understand how can I change severity type to enum, what I've tried:

export enum Severity {
  Critical = 1,
  Major = 2,
  Minor = 3,
  Warning = 2,
  Info = 1,
  Clear = 0,
}

    import { IsEnum } from 'class-validator';
    import { ApiProperty } from '@nestjs/swagger';
    import { Severity} from '../enums/severities';

    export class createEventDto {
      @IsEnum(Severity)
      @ApiProperty({
        description: 'description of the severity property',
      })
      severity: Severity;
    }

Although it is working, swagger looks a bit off (example is incorrect and the description for severity in schema becomes nested in brackets:

score 13 · Accepted Answer · edited May 04 '23 at 17:14

13

If you want to express an enum on SwaggerUI, you need to provide enum property to ApiProperty decorator

 import { IsEnum } from 'class-validator';
 import { ApiProperty } from '@nestjs/swagger';
 import { Severity} from '../enums/severities';

 export class createEventDto {
   @IsEnum(Severity)
   @ApiProperty({
     description: 'description of the severity property',
     enum: Severity
   })
   severity: Severity;
 }

edited May 04 '23 at 17:14

Abhishek Pankar

723
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answered Jun 10 '20 at 15:12

Chau Tran

4,668
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39

Thanks, I was looking into that doc, but that specific example somehow escaped my eyes.. :/ – Aurimas Stands with Ukraine Jun 11 '20 at 08:55
Actually that link now gets redirected to https://docs.nestjs.com/openapi/introduction, where there is no mention about enums. Nest's swagger integration seems to be a poorly documented topic – Apperside Sep 05 '21 at 09:45

Nestjs IsEnum dto validation and swagger

1 Answers1