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How do you model your contact list with self-promotion and category?

The fight of my head with the model after

  • The user has many categories of contacts (family / friends)
  • There are many contacts in one category of contacts.
  • One contact can be in one or several contact categories.

In the end, I get the following, but, in my opinion, there should be a better solution.

class User < ActiveRecord::Base  
    has_many :contact_groups  

    def get_all_contacts  
        self.contact_groups.each do |group|  
        contacts << group.users  
    end  
end  

class ContactGroup < ActiveRecord::Base  
    has_and_belongs_to_many :users  
end
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2 answers

Assumptions

  • This is a system for many users, not just one, so you need to specify the owner in the Contact and Group entries using a foreign key.
  • A contact can belong to several groups, and a group has several contacts, so this has_and_belongs_to_many relationship.

Migration

Create user table:

class CreateUsers < ActiveRecords::Migrations
  def change
    create_table :users do |t|
      t.text :username
    end
  end
end

. , , , .

class CreateContacts < ActiveRecord::Migrations
  def change
    create_table :contacts do |t|
      t.references :owner
      t.references :user
    end
  end
end

. , .

class CreateGroups < ActiveRecord::Migrations
  def change
    create_table :groups do |t|
      t.references :owner
      t.text :name
    end
  end
end

has_and_belongs_to_many . ; , .

class CreateContactsGroups < ActiveRecord::Migrations
  def change
    create_table :contacts_groups do |t|
      t.references :contact
      t.references :group
    end
  end
end

. , , , - "owner_id". .

class User
  has_many :contacts, :foreign_key => 'owner_id'
  has_many :groups, :foreign_key => 'owner_id'
end

. , "" . , Contact ( Rails-, ), : , , : . , .

class Contact
  belongs_to :owner, :class_name => 'User'
  belongs_to :user
  has_and_belongs_to_many :groups
end

. .

class Group
  belongs_to :owner, :class_name => 'User'
  has_and_belongs_to_many :contacts
end

contacts_groups, .

, :

@user.contacts # all of the user contacts
@user.groups # all of the user groups
@user.groups.find(id).contacts # all the contacts in a group
@user.contacts.find(id).groups # all of the groups that a contact belongs to

@benrmatthews, .

, , Contact ID , contact_groups, , .

:

resources :contact_groups, only: [:create]

, :

class ContactGroupsController < ApplicationController
  def create
    @contact = Contact.find(params[:contact_id])
    @group = Group.find(params[:group_id])
    @contact.groups << @group
  end
end

, contact_id group_id . :

# This is for adding the contact to a group
form_tag contact_groups_path do
  hidden_field_tag :contact_id, @contact.id
  select_tag :group_id, options_from_collection_for_select(Group.all, :id, :name)
  submit_tag "Add to Group"
end

, contact_id select, . , contact_id group_id , , .

+6

has_many:

class User
    has_many :contacts
    has_many :contact_groups, :through => :contacts
end

class Contact
    belongs_to :user
    has_many :contact_groups
end

class ContactGroup
    belongs_to :contacts
end

.

+2

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