Agile Web Development with Rails, Edition 4

12.3 Iteration G3: Downloading an eBook 12.1 Iteration G1: Capturing an Order

12.2 Iteration G2: Atom Feeds

Demonstrate various respond_to/format options, as well as "through" relations and basic authentication.

Define a "who_bought" member action

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 < ActiveRecord::Base
  has_many :line_items
  has_many :orders, through: :line_items
  #...
end

Add to the routes

edit config/routes.rb
Depot::Application.routes.draw do
  resources :orders
 
  resources :line_items
 
  resources :carts
 
  get "store/index"
  resources :products do
    get :who_bought, on: :member
  end
 
  # The priority is based upon order of creation:
  # first created -> highest priority.
  # See how all your routes lay out with "rake routes".
 
  # You can have the root of your site routed with "root"
  root 'store#index', as: 'store'
  # ...
end

Fetch the Atom feed

curl --max-time 15 --silent --user dave:secret http://localhost:3000/products/2/who_bought.atom
<?xml version="1.0" encoding="UTF-8"?>
<feed xml:lang="en-US" xmlns="http://www.w3.org/2005/Atom">
  <id>tag:localhost,2005:/products/2/who_bought</id>
  <link rel="alternate" type="text/html" href="http://localhost:3000"/>
  <link rel="self" type="application/atom+xml" href="http://localhost:3000/products/2/who_bought.atom"/>
  <title>Who bought CoffeeScript</title>
  <updated>2015-04-25T07:41:24Z</updated>
  <entry>
    <id>tag:localhost,2005:Order/1</id>
    <published>2015-04-25T07:41:24Z</published>
    <updated>2015-04-25T07:41:24Z</updated>
    <link rel="alternate" type="text/html" href="http://localhost:3000/orders/1"/>
    <title>Order 1</title>
    <summary type="xhtml">
      <div xmlns="http://www.w3.org/1999/xhtml">
        <p>Shipped to 123 Main St</p>
        <table>
          <tr>
            <th>Product</th>
            <th>Quantity</th>
            <th>Total Price</th>
          </tr>
          <tr>
            <td>CoffeeScript</td>
            <td>1</td>
            <td>$36.00</td>
          </tr>
          <tr>
            <th colspan="2">total</th>
            <th>$36.00</th>
          </tr>
        </table>
        <p>Paid by Check</p>
      </div>
    </summary>
    <author>
      <name>Dave Thomas</name>
      <email>customer@example.com</email>
    </author>
  </entry>
</feed>

Look at the headers

curl --max-time 15 --silent --dump - --output /dev/null --user dave:secret http://localhost:3000/products/2/who_bought.atom
HTTP/1.1 200 OK 
X-Frame-Options: SAMEORIGIN
X-Xss-Protection: 1; mode=block
X-Content-Type-Options: nosniff
X-Ua-Compatible: chrome=1
Etag: "d1f97826eb7fdbef0a5b835a3ea5a8a9"
Last-Modified: Sat, 25 Apr 2015 07:41:24 GMT
Content-Type: application/atom+xml; charset=utf-8
Cache-Control: max-age=0, private, must-revalidate
X-Request-Id: 11a56588-0c18-43d0-9505-534e58adbb57
X-Runtime: 0.011231
Server: WEBrick/1.3.1 (Ruby/2.1.5/2014-11-13)
Date: Sat, 25 Apr 2015 07:41:25 GMT
Content-Length: 1324
Connection: Keep-Alive
 
curl --max-time 15 --silent --dump - --output /dev/null --user dave:secret http://localhost:3000/products/2/who_bought.atom -H 'If-None-Match: "d1f97826eb7fdbef0a5b835a3ea5a8a9"'
HTTP/1.1 304 Not Modified 
X-Frame-Options: SAMEORIGIN
X-Xss-Protection: 1; mode=block
X-Content-Type-Options: nosniff
X-Ua-Compatible: chrome=1
Etag: "d1f97826eb7fdbef0a5b835a3ea5a8a9"
Last-Modified: Sat, 25 Apr 2015 07:41:24 GMT
Cache-Control: max-age=0, private, must-revalidate
X-Request-Id: 19c5ba6e-5683-4b60-b5f3-d34551f8a334
X-Runtime: 0.003333
Server: WEBrick/1.3.1 (Ruby/2.1.5/2014-11-13)
Date: Sat, 25 Apr 2015 07:41:25 GMT
Connection: Keep-Alive
 
curl --max-time 15 --silent --dump - --output /dev/null --user dave:secret http://localhost:3000/products/2/who_bought.atom -H 'If-Modified-Since: Sat, 25 Apr 2015 07:41:24 GMT'
HTTP/1.1 304 Not Modified 
X-Frame-Options: SAMEORIGIN
X-Xss-Protection: 1; mode=block
X-Content-Type-Options: nosniff
X-Ua-Compatible: chrome=1
Etag: "d1f97826eb7fdbef0a5b835a3ea5a8a9"
Last-Modified: Sat, 25 Apr 2015 07:41:24 GMT
Cache-Control: max-age=0, private, must-revalidate
X-Request-Id: b82658ec-9d18-4666-a186-58892b508321
X-Runtime: 0.005676
Server: WEBrick/1.3.1 (Ruby/2.1.5/2014-11-13)
Date: Sat, 25 Apr 2015 07:41:25 GMT
Connection: Keep-Alive
 

12.3 Iteration G3: Downloading an eBook 12.1 Iteration G1: Capturing an Order