使用显式类型

export interface Foo {
  boo: string[];
  boo2: string;
  boo3: string;
  ..etc
}

和

@ApiModelPropertyOptional({ type: Foo })
@IsOptional()
readonly foo: Foo;

请改用类
示例：

import { ApiProperty, ApiPropertyOptional } from '@nestjs/swagger';
import { IsArray, IsNotEmpty, IsString } from 'class-validator';
import { Type } from 'class-transformer';

export class StickerRequest {

    @IsNotEmpty()
    @IsString()
    @ApiProperty({ example: 'sticker 01' })
    readonly name: string;

    @ApiPropertyOptional({ example: 'This is sticker description' })
    readonly description?: string;

    @ApiPropertyOptional({ example: 'ami-01, ami-02' })
    readonly tags?: string;

}

export class CollectionRequest {

  @ApiProperty({ example: 'Ami' })
  @IsNotEmpty()
  @IsString()
  readonly collectionName: string;

  @ApiPropertyOptional({ example: 'This is collection description' })
  readonly description?: string;

  @ApiProperty({ example: 'fffa73e4efca9245489e2bac' })
  @IsNotEmpty()
  @IsString()
  readonly author: string;

  @ApiProperty({ type: StickerRequest }) <------- Here
  @IsNotEmpty()
  @IsArray()
  @Type(() => StickerRequest)
  stickers: StickerRequest[];

}

不要创建/使用接口的创建子数据（如果需要，可以使用导出或不使用导出），例如：

export class SubDto {
    @ApiModelProperty({ type: String })
    @IsString()
    readonly subStringOne: string;

    @ApiModelProperty({ type: String })
    @IsString()
    readonly subStrinTwo: string;
}

export class MainDto {

    @ApiModelProperty({ type: String })
    @IsString()
    readonly mainStringOne: string;

    @ApiModelProperty({ type: [SubDto] })
    @IsArray()
    readonly mainArray: SubDto[];

    // or do the same thing for objects
    @ApiModelProperty({ type: SubDto })
    @IsJSON() // @IsOject doesn't exist in Nestjs so I use @IsJSON().
    readonly mainObject: SubDto;
}

我相信你使用的是旧版本的nestjs，因为@ApiModelProperty现在被称为@ApiProperty .我建议你升级nestjs和swagger到它们的最新版本，并按照以下步骤操作，对我来说效果很好：
https://docs.nestjs.com/recipes/swagger#openapi-swagger
希望能有所帮助。