Agile Web Development with Rails 7: Missing instructions on building an Atom feed (page 181)

@rubys

On the page 181 it’s said:

We also don’t have time to build a full-fledged admin user interface right now, so we’ll take advantage of the various Atom feed readers that exist and have our app export all the orders as an Atom feed so the customer can quickly see what’s been purchased.

Looks like instructions on creating an Atom feed should follow right there, but they are missing. On the page 182 it’s said:

What We Just Did:

  • We provided a feed so the administrator can monitor incoming orders.

And on the page 183:

Playtime
Here’s some stuff to try on your own:

  • Get HTML- and JSON-formatted views working for who_bought requests. Experiment with including the order information in the JSON view by rendering @product.to_json(include: :orders). Do the same thing for XML using ActiveModel::Serializers::Xml.2

Looks like this task is related to the Atom feed that should have been built above.

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yep, i noticed that too.

The book is missing a subsection called Iteration G2: Atom. In the previous version of the book “AWDR-6,” four pages (189-192) are dedicated to Atom feeds.

@rubys

Is there anyway we can get the full missing section? I want to add an atom feed so I can do the Playtime sections properly like I have with all the previous chapters…

XML seems to be increasingly de-emphasized these days, but here is the essence of what was in that section:

edit app/controllers/products_controller.rb

  def who_bought
    @product = Product.find(params[:id])
    @latest_order = @product.orders.order(:updated_at).last
    if stale?(@latest_order)
      respond_to do |format|
        format.atom
      end
    end
  end

Define an Atom view (using the Atom builder)
edit app/views/products/who_bought.atom.builder

atom_feed do |feed|
  feed.title "Who bought #{@product.title}"
 
  feed.updated @latest_order.try(:updated_at) 
 
  @product.orders.each do |order|
    feed.entry(order) do |entry|
      entry.title "Order #{order.id}"
      entry.summary type: 'xhtml' do |xhtml|
        xhtml.p "Shipped to #{order.address}"
 
        xhtml.table do
          xhtml.tr do
            xhtml.th 'Product'
            xhtml.th 'Quantity'
            xhtml.th 'Total Price'
          end
          order.line_items.each do |item|
            xhtml.tr do
              xhtml.td item.product.title
              xhtml.td item.quantity
              xhtml.td number_to_currency item.total_price
            end
          end
          xhtml.tr do
            xhtml.th 'total', colspan: 2
            xhtml.th number_to_currency \
              order.line_items.map(&:total_price).sum
          end
        end
 
        xhtml.p "Paid by #{order.pay_type}"
      end
      entry.author do |author|
        author.name order.name
        author.email order.email
      end
    end
  end
end

Add "orders" to the Product class
edit app/models/product.rb

class Product < ApplicationRecord
  has_many :line_items
  has_many :orders, through: :line_items
  #...
end
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