[V5] Conditional Relationship Definition

[remidosol]

Hello folks 👋

I'm confused about defining relationships by my User model's role.

I've a enum type that contains 'admin', 'designer', 'staff' elements and used for User's role column type.
I want to define relationships by these roles.
e.g. if the role is 'designer', HasMany relationship will be defined between User and Design model.
And if the role is 'staff', HasMany relationship will be defined between User and StaffImage model.

Is there any solution except creating models by these roles? Thanks already.

[hashtd]

First thought
I think you have to create HasMany relationship at Model level for User.

at Controller/Business logic level you can check role to inset/update receptive relationship

also at api json serialization based on role you can only pull that of specific user role conditional relationship

On Second thought

only possible (guessing/speculation) alternative is to use override boot() method & based on role use setRelatedForMany method to set relationship

https://github.com/adonisjs/lucid/blob/77600cc00eb2629eec5e02018f4c247b603f6cd5/src/Orm/Relations/HasMany/index.ts#L168

but here loading data from table row then using setRelatedForMany() will be ideal flow, since you need role to determine which relationship need to be initialize

[remidosol]

May you give me an example code for both of your thoughts (especially your second thought)?

[fairhat]

If you have a fixed amount of roles (lets say 3 in your case), create models for each role (admin, designer, staff) which includes specific data for each role
For every role, assign its related relationship (design, staffImage, etc.)

In your controllers:
Check for the role of user (admin, designer, staff) and then fetch its role-model instance and then fetch the related data to the role

Example:
User (Staff) -> StaffProfile -> StaffImage

User (Designer) -> DesignerProfile -> Design

If this is too much abstraction, you could just assign all relationships to the user model and only query each when needed.

[fairhat]

Example with Users and Profiles (in your case you would use Profiles for your Roles)

https://preview.adonisjs.com/guides/model-relations/has-one

[remidosol]

Thanks, I think this will be useful.