How can i post a DTO that contain an array of entities? - nestjs

Question

I have a couple of questions about NestJS and TypeOrm.
First, how to pass an array of strings to DTO? I tried just to use :string[] type, but the compiler gives an error.
This is my Post entity:
#Entity('posts')
export class Post {
#PrimaryGeneratedColumn()
id: number;
#ManyToOne(() => User, user => user.posts, { cascade: true })
author: number;
#Column({ type: 'timestamp' })
date: Date;
#Column()
text: string;
#Column({ default: 0 })
likes: number;
#OneToMany(() => Photo, photo => photo.post, { cascade: true })
photos: Photo[];
}
And CreatePostDto:
export class CreatePostDto {
authorId: number;
date: Date;
text?: string;
// photos?: string[];
}
And the second question: How can i save to the repository every photo (keeping the connection with post), posts to the posts repo and update user by adding new post binded to him.
I tried something like this, but it won't work obviously.
async create(createPostDto: CreatePostDto) {
const post = this.postsRepository.create(createPostDto);
const user = await this.usersRepository.findOne(createPostDto.authorId);
return this.postsRepository.save({author: user, date: createPostDto.date, text: createPostDto.text});
}

Answer 1

What you missed here is saving photos before bind them with the post, here's an example:
async create(createPostDto: CreatePostDto) {
let photos:Array<Photo> = [] ; array of type photo entity
for(let urlPhoto of createPostDto.photos)
{
let photo = await this.imageRepository.save({url : urlPhoto }); you must save the photos first
photos.push(photo);
}
const user = await this.usersRepository.findOne(createPostDto.authorId);
return this.postsRepository.save({author: user, date: createPostDto.date, text:
createPostDto.text,photos:photos});
}

Answer 2

#Entity()
export class User {
#PrimaryGeneratedColumn()
id: number
#Column("simple-array")
names: string[]
}