User and Project relationship

So I have a User model created with devise and a Project model. A Project should have one Project owner and project members. So now I have no idea how to create the relations in my models.

What I have tried is have in my User model has_many :projects and in my Project model belongs_to :user but the problem with this is that the project is attached to only one User so i can't add any other users to it.

I tried changing it so that Project has_many :users but this causes my registration with devise to stop working since a user should belong to a project.

Something else I thought about doing is creating a class ProjectOwner and a class ProjectMember and then set that a Project has_many :ProjectMember and has_one :ProjectOwner. And set that a user has_many :ProjectMember and has_many :ProjectOwner since a User can be a project owner in many Projects and be a ProjectMember in others.

Or can I just set that a Project has an attribute of type User called ProjectOwner and another attribute of type User array that named ProjectMembers?

Since I'm pretty new to RoR, I'm not sure what is the right approach for this kind of situation.

Solution

What it looks like is you want a User, Role (with ProjectOwner and ProjectMember by STI), and Project

class  User < ApplicationRecord
  has_many :roles
  has_many :projects, through: :roles
end

class Role < ApplicationRecord
  belongs_to :user
  belongs_to :project

  #Code that applies to both project owners and members
end

class ProjectOwner < Role
  #project owner specific code
end

class ProjectMember < Role
  #project member specific code
end

class Project < ApplicationRecord
  has_many :project_members
  has_many :members, class_name: "User", through: :project_members
  has_one  :project_owner
  has_many :owners, class_name: "User", through: :project_owner
end

Check out this article to help set up single table inheritance