Controller helper method not receiving/defining parameters?

rubyonrails-talk
1

I have a pretty basic helper method which filters/searches through an existing active record result set:

module ReactEndpoints::ProductsHelper
    def filter_and_search_products(products, params)
        pry
        products = products.search_products(params[:search])
        # filtering etc
        return products
    end
end

The problem is, when I stick a pry call in there, and try to inspect products, I get:

[23] pry(#<#<Class:0x000055d249081710>>)> products
  CACHE InvProcure::Product Load (0.0ms)  SELECT "inv_products".* FROM "inv_products" WHERE "inv_products"."customer_id" = $1 ORDER BY description asc LIMIT $2  [["customer_id", 23], ["LIMIT", 11]]
  ↳ app/helpers/react_endpoints/products_helper.rb:3:in `filter_and_search_products'
  CACHE InvProcure::Product Load (0.0ms)  SELECT "inv_products".* FROM "inv_products" WHERE "inv_products"."customer_id" = $1 ORDER BY description asc LIMIT $2  [["customer_id", 23], ["LIMIT", 11]]
  ↳ app/helpers/react_endpoints/products_helper.rb:3:in `filter_and_search_products'
  CACHE InvProcure::Product Load (0.0ms)  SELECT "inv_products".* FROM "inv_products" WHERE "inv_products"."customer_id" = $1 ORDER BY description asc LIMIT $2  [["customer_id", 23], ["LIMIT", 11]]
  ↳ app/helpers/react_endpoints/products_helper.rb:3:in `filter_and_search_products'
  CACHE InvProcure::Product Load (0.0ms)  SELECT "inv_products".* FROM "inv_products" WHERE "inv_products"."customer_id" = $1 ORDER BY description asc LIMIT $2  [["customer_id", 23], ["LIMIT", 11]]
  ↳ app/helpers/react_endpoints/products_helper.rb:3:in `filter_and_search_products'
  CACHE InvProcure::Product Load (0.0ms)  SELECT "inv_products".* FROM "inv_products" WHERE "inv_products"."customer_id" = $1 ORDER BY description asc LIMIT $2  [["customer_id", 23], ["LIMIT", 11]]
  ↳ app/helpers/react_endpoints/products_helper.rb:3:in `filter_and_search_products'
  CACHE InvProcure::Product Load (0.0ms)  SELECT "inv_products".* FROM "inv_products" WHERE "inv_products"."customer_id" = $1 ORDER BY description asc LIMIT $2  [["customer_id", 23], ["LIMIT", 11]]
  ↳ app/helpers/react_endpoints/products_helper.rb:3:in `filter_and_search_products'
  CACHE InvProcure::Product Load (0.0ms)  SELECT "inv_products".* FROM "inv_products" WHERE "inv_products"."customer_id" = $1 ORDER BY description asc LIMIT $2  [["customer_id", 23], ["LIMIT", 11]]
  ↳ app/helpers/react_endpoints/products_helper.rb:3:in `filter_and_search_products'
  CACHE InvProcure::Product Load (0.0ms)  SELECT "inv_products".* FROM "inv_products" WHERE "inv_products"."customer_id" = $1 ORDER BY description asc LIMIT $2  [["customer_id", 23], ["LIMIT", 11]]
  ↳ app/helpers/react_endpoints/products_helper.rb:3:in `filter_and_search_products'
NameError: undefined local variable or method `products' for #<#<Class:0x000055d249081710>:0x000055d2490a2280>
Did you mean?  @products
from (pry):4:in `__pry__'

It seems to think products is undefined, but if I type @products I can see data.

class ReactEndpoints::ProductsController < ApplicationController
    def index
        @products = current_customer.products

        if params[:query].present?
            params[:query] = JSON.parse(params[:query])
            @products = helpers.filter_and_search_products(@products, params[:query])
        end

        page = params[:query] && params[:query][:page] || 1
        per = params[:query] && params[:query][:pageSize] || 10

        @products = @products.page(page).per(per)
    end
end
2

For whatever reason, it looks like pry doesn’t work properly within the context of these helper methods.

3

It’s generally considered bad practice to define namespaced classes in ruby (and particularly rails apps due to the autoloading), and there’s a plethora of literature out there detailing issues around structuring your code in this way.

# bad practice: this causes ReactEndpoints to be a class, which 
# much include an explicit module prefix when performing 
# constant lookup 
class ReactEndpoints::ProductsController < ApplicationRecord
end

# best practice: ReactEndpoints is now a module that can perform 
# constant lookup without a namespace prefix
module ReactEndpoints
  class ProductsController < ApplicationRecord
  end
end

Read up on namespaced classes and modules in Ruby for a better explanation.