Can View call some Model methods in Rails?

Question

First let me explain an example:

In Model:

class Product < ActiveRecord::Base
  has_many :line_items

  def income
     self.line_items.sum(:price)
  end

  def cost
    self.line_items.sum(:cost)
  end

  def profit
    self.income - self.cost
  end
end

Then in Controller:

def show
  @products = Product.all
end

And in View:

<% @products.each do |product| %>
Product Name: <%= product.name %>
Product Income: <%= product.income %>
Product Cost: <%= product.cost %>
Product Profit: <%= product.profit %>
<% end %>

Is it a good practice to call model methods from view?

When I searched for that, I found many people saying it is NOT a good practice to ever call model methods or access DB from views.

And on the other hand, some others said that don't call class methods or any method updates the DB from view but you can access any method that only retrieve data.

Then, is this code a good practice?

Answer 1

Its perfectly fine to call the object-methods/attributes from the view, as long as the call would not change the data. I mean, call readers/getters. A Bad practice would be to call/invoke methods that update/delete the data. Don't call setters.

Also, if there is any complex computation involved, resort to helpers.