I have an app with Two Models Stadium & Team, they have a many-to-many relationship and are joined in the middle by a join table.
My current structure looks like this:
class Team < ActiveRecord::Base
has_many :stadiumteams, :class_name => 'StadiumTeam'
has_many :stadiums, :through => :stadiumteams
end
class Stadium < ActiveRecord::Base
has_many :stadiumteams, :class_name => 'StadiumTeam'
has_many :teams, :through => :stadiumteams
end
class StadiumTeam < ActiveRecord::Base
belongs_to :stadium
belongs_to :team
end
This relationship show “current residents for a stadium”. But now I also want to have a relationship that can display old residents.
For example Tottenham (Team) used to play at White Hart Lane (Stadium) But now play at (Wembley) Stadium.
I am planning to do the following. But I am unsure if this will work or if there is a better way to do it?
Team
class Team < ActiveRecord::Base
has_many :stadiumteams, :class_name => 'StadiumTeam'
has_many :stadiums, :through => :stadiumteams
#has_many :oldstadiums, :class_name => 'OldStadium'
#has_many :stadiums, :through => :oldstadiums
end
Stadium
class Stadium < ActiveRecord::Base
has_many :stadiumteams, :class_name => 'StadiumTeam'
has_many :teams, :through => :stadiumteams
#has_many :oldstadiums, :class_name => 'OldStadium'
#has_many :teams, :through => :oldstadiums
end
New Join Table
class OldStadium < ActiveRecord::Base
belongs_to :stadium
belongs_to :team
end
Any help is very appreciated!
EDIT: (Input fields) Here's how the code for my inputs currently looks:
<%= f.association :teams, label: 'Current Residents', class:'select2-field', placeholder: "Select teams", collection: @teams, input_html: { multiple: true }, hint: 'Select one or multiple teams.'%>
<%= f.association :teams, label: 'Old Residents', class:'select2-field', placeholder: "Select teams", collection: @teams, input_html: { multiple: true }, hint: 'Select one or multiple teams.' %>
And my params
def stadium_params
params.require(:stadium).permit(:name, :capacity, :city, :country, :location_name, :address, :longitude, :latitude, :image, :surface, :official_opening_date, :cost, :web_url, :also_known_as, :record_attendance, :team_ids => [])
end
You can define relations with a lambda to append an additional where
clause in the relation:
class Team < ActiveRecord::Base
has_many :stadiumteams, :class_name => 'StadiumTeam'
has_many stadiums, :through => :stadiumteams
has_many :current_stadiums, ->{ where(stadiumteams: { current_home: true }) }, :through => :stadiumteams, :class_name => 'Stadium', :source => :stadium
has_many :previous_stadiums, ->{ where(stadiumteams: { current_home: false }) }, :through => :stadiumteams, :class_name =>'Stadium', :source => :stadium
end
class Stadium < ActiveRecord::Base
has_many :stadiumteams, :class_name => 'StadiumTeam'
has_many :teams, :through => :stadiumteams
has_many :current_teams, ->{ where(stadiumteams: { current_home: true }) }, :through => :stadiumteams, :class_name => 'Team', :source => :team
has_many :previous_teams, ->{ where(stadiumteams: { current_home: false }) }, :through => :stadiumteams, :class_name =>'Team'. :source => :team
end
class StadiumTeam < ActiveRecord::Base
belongs_to :stadium
belongs_to :team
end
And then you should be able to do (in rails console):
team = Team.first
stadium = Stadium.first
team.previous_stadiums <<
team.save
team.reload.previous_stadiums.include?(stadium)
# => should return true
So this way you can simply use in your UI a input for the association :previous_teams
and :current_teams
:
f.association :current_teams, #...