Add custom select and map to property of entity

Issue type:

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Database system/driver:

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TypeORM version:

[ ] latest [ ] @next [ ] 0.x.x (or put your version here)

Steps to reproduce or a small repository showing the problem: What I to accomplish is to add a custom select that maps to a property of my Entity. I’ve found an work around but would like to know if there is an easier/cleaner way to do this.

So I’ve my model:

@Entity('groups')
export class Group extends BaseEntity{

    @PrimaryGeneratedColumn()
    id: number;

    @ManyToMany(type => User, user => user.groups)
    @JoinTable({
        name: 'groups_users',
        joinColumn: {
            name: 'group_id',
            referencedColumnName: 'id'
        },
        inverseJoinColumn:
            {name: 'user_id',
                referencedColumnName: 'id'
            }
    })
    users: User[];

    active: boolean;
}

This entity has a ManyToMany relationship to User. The JoinTable groups_users has one extra column active this active indicates if the group that the user is linked to is visible.

When I query the groups to get all the groups for one user (also the inactive groups) I do this:

let query = this.groupRepository
            .createQueryBuilder('group')
            .innerJoin('groups_users', 'gu')
            .innerJoin('group.users', 'user', 'user.deleted_at is null AND group_user.user_id = :id',
                {id: userId})
            .orderBy('group.id', 'ASC')
            .andWhere('group.deleted_at IS NULL');

As you can see the Group entity has a property called active. As for now the active property is not seen by typeorm so what I did was the following:

I added this to the active property:

 @Column('tinyint', {
        nullable: true,
        select: false
    })
    active: boolean;

By setting select to false the other queries won’t break (since active isn’t a real column inside the group table).

Now I added this to the query:

.addSelect(s => s.select('active').from('groups_users', 'gu').where('gu.group_id = group.id AND gu.user_id = :id', {id: userId}), 'group_active')

By doing this the active property is filled for each user and the active is true or false according the 0 or 1 in JoinTable.

To query I ended up with is:

let query = this.groupRepository
            .createQueryBuilder('group')
            .addSelect(s => s.select('active').from('groups_users', 'gu').where('gu.group_id = group.id AND gu.user_id = :id', {id: userId}), 'group_active')
            .innerJoin('groups_users', 'gu')
            .innerJoin('group.users', 'user', 'user.deleted_at is null AND group_user.user_id = :id',
                {id: userId})
            .orderBy('group.id', 'ASC')
            .andWhere('group.deleted_at IS NULL');

which leaves me with the correct output. Now this seems a little bit of a hack or is this the propper way to do this?