CODEWITHSUNDEEP
ruby-on-railsrubyruby-on-rails-4rails-activerecord
canigetabreak
canigetabreak

Reputation: 77

Proper way to set up models and relationships for a rails app, has_many through

I am having a hard time getting my head around the best way to set up my models and relationships in rails as I'm need to rails, mvc, and active record conventions.

Consider three tables:

users

rails generate scaffold User username:string email:string password:string

games

rails generate scaffold Game user_id:integer name:string description:string type:string

game_rosters

rails generate scaffold GameRoster user_id:integer game_id:integer level:integer status:string

Users can create games (this is the user_id field in the games table for the "owner"). The creator may or may not be in the actual game (optional record for the creator in the game_rosters table).

Each game has many users which are apart of the game (located in game_rosters).

So I am thinking I should have two relationships for the user - has_many: games for the games they have created, and has_many: games, through: game_rosters for the games that user is a part of..

class User < ActiveRecord::Base
    has_many :game_rosters
    has_many :games, through: :game_rosters

    has_many :games
end

class Game < ActiveRecord::Base
    has_many :game_rosters
    has_many :users, through: :game_rosters
end

class GameRoster < ActiveRecord::Base
    belongs_to :user
    belongs_to :game
end

But I'm not sure if this is the right set up, and I can't get it working properly.. I have the above set up, and the following for trying to print results:

<p>
  <strong>My Games:</strong>
  <% @user.games.each do |game| %>
  <br><%= game.name %>
  <% end %>
</p>


<p>
  <strong>Participants:</strong>
  <% @game.users do |user| %>
  <br><%= game.user.name %>
  <% end %>
</p>

I can print the "My Games" from the has_many: games relationship, but can't print the "Participants" from the has_many :through relationship.

Any direction would be appreciated, thanks.

Upvotes: 0

Views: 956

Answers (2)

tihom
tihom

Reputation: 8003

Also want to add that you should not have the same name games for different association in the User model. As last one is overwriting the first. Smthing like this should work.

class User < ActiveRecord::Base

    has_many :owned_games, :foreign_key => "user_id", :class_name => "Game"

    has_many :game_rosters
    has_many :games, through: :game_rosters


end

class Game < ActiveRecord::Base

    belongs_to :owner, :foreign_key => "user_id", :class_name => "Game"

    has_many :game_rosters
    has_many :users, through: :game_rosters
end

class GameRoster < ActiveRecord::Base
    belongs_to :user
    belongs_to :game
end

Accessing the associations for a user

 # All the games a user is involved in 
 user.games

 # All the games a user owns
 user.owned_games

Accessing associations for a game

 #All the users involved in the game
 game.users

# Owner of the game
 game.owner

Upvotes: 3

lurker
lurker

Reputation: 58284

Try:

<p>
  <strong>Participants:</strong>
  <% @game.users.each do |user| %>
  <br><%= user.name %>
  <% end %>
</p>

Upvotes: 1

Related Questions