访问存储在联接表中的列-Rails

Question

I have a join table called ProductFeatures which joins Product and Feature instances via has_many: ..., through: product_features , and has an additional column called rating .

I want to add .rating method on Feature which will return a rating float based on specific product instance that is calling it. Something like:

Product.find(...).features.first.rating #=> should specific product_feature rating

I've tried:

• passing caller_id as an argument to .rating . This works, but makes me use product.id each time I want to get a specific product rating feature.
• Obtaining a caller instance id from inside the method using .caller (with binding_of_caller , or vanilla Ruby), but .caller does not seem to let me get a calling instance id, and would also fail in tests as the caller would be the spec's ExampleGroup

Answer 1

You can get these data with other way.

• I want to add #rating method on Feature which will return a rating float based on specific product instance that is calling it. Something like:

## Controller add this code snipped
   get_feature = Product.find(...).features
   rating(get_feature)

   protected

   def rating(get_all_feature)
     all_rating = []
     get_all_feature.each do |feature|
       all_rating <<  feature.product_features.each { |u| u.rating }
     end
     all_rating
   end

Hope this help you!