Arrays and objects are not managed properly when located in first level of @Query()

[arnaud-cortisse]

I'm submitting a...

[ ] Regression 
[ x] Bug report
[ ] Feature request
[ ] Documentation issue or request
[ ] Support request => Please do not submit support request here, instead post your question on Stack Overflow.

Current behavior

I created these DTOs:

class ObjectDto {
  @ApiProperty()
  field: string;
}

export class HelloWorldDto {
  @ApiProperty({
    isArray: true,
    type: ObjectDto,
  })
  arrayOfObjectsDto: ObjectDto[];
}

And expected them as query parameters:

  @Get('/Not Working')
  getHello(@Query() helloWorldDto: HelloWorldDto): string {
    return this.appService.getHello();
  }

I got the following output:

Expected behavior

I would expect something like this:

As you can see, it's an actual array of objects.

I was able to get it to work by doing the following:

class ObjectDto {
  @ApiProperty()
  field: string;
}

export class Params {
  @ApiProperty({
    isArray: true,
    type: ObjectDto,
  })
  arrayOfObjectsDto: ObjectDto[];
}

export class HelloWorldDto2 {
  @ApiProperty()
  params: Params;
}

As you can see, arrays seem to be declared correctly when they are located in the deeper level in the DTO.
However, this is not a viable option, since the path HelloWorldDto2.params actually doesn't exist...

Minimal reproduction of the problem with instructions

See https://github.com/arnaud-cortisse/nestjs-openapi-array-of-objects-bug

What is the motivation / use case for changing the behavior?

I want to be able to declare arrays of complex objects in the first level of DTOs

Environment

Nest version: 7.5.1

 
For Tooling issues:
- Node version: node:alpine docker image
- Platform: node:alpine docker image

[kamilmysliwiec]

Would you like to create a PR for this issue?

[arnaud-cortisse]

@kamilmysliwiec I've just created a PR here: #1113 👍

[kamilmysliwiec]

Thanks! Let's track this here #1113