Rails控制台帮助需要HABTM关系

rails generate scaffold Role name:string

rails generate scaffold Permission name:string

class Role < ApplicationRecord
  has_and_belongs_to_many :permissions, class_name: 'Permission'
end

class Permission < ApplicationRecord
  has_and_belongs_to_many :roles, class_name: 'Role'
end

Role.create!(name: 'admin')
Permission.create!(name: 'create_post')
Permission.create!(name: 'edit_post')

role = Role.find_by(name: 'admin')
permission = Permission.find_by(name: 'create_post')

role.permissions << permission

role = Role.find_by(name: 'admin')
permission = Permission.find_by(name: 'create_post')

role.permissions # returns [permission]
permission.roles # returns [role]