Question

I need to create a join model called CarStoreTracker for Car and Store with both having many of each other.

class Car < ActiveRecord::Base
  has_many :carstoretrackers        # It seems to work
  has_many :stores, :through => :carstoretrackers  # I bet the naming is not being recognized by Rails convention
end

class Store < ActiveRecord::Base
  has_many :carstoretrackers        # It seems to work
  has_many :cars, :through => :carstoretrackers  # Same issue
end

class CarStoreTracker < ActiveRecord::Base
  belongs_to :store
  belongs_to :car
end

The CarStoreTracker has

car_id and store_id on its table.

When I run:

 > CarStoreTracker.first.car
 > CarStoreTracker.first.store

They both work.

But

Store.first.cars
Car.first.stores
Store.carstoretrackers
Car.carstoretrackers

Non of them work.
NameError: uninitialized constant “CURRENTMODEL”::Carproducttracker

So, I scrapped the CarProductTracker and I just used the name Tracker for model and everything works.

What’s happening? What the name convention is for Rails in this case?

Answer 1

You need to put underscores after each word when defining has_many and other relationships.

So it would be :car_store_trackers