0 - Intro.md

Vacuum with Rails

Goal: Displaying products from the Amazon Product Advertising API.

Status:

• Live demo: http://runnable.com/U9RWGQXGdYRzmRDZ/amazon-api

NOT WORKING

undefined method `any?' for nil:NilClass
Extracted source (around line #2):
  <h1>Products from the Amazon API</h1>
  <% if @products.any? %>
    <% @products.each do |product| %>
      <div class="product">
        <%= link_to image_tag(product.image.url), product.url %>

1 - main_controller.rb

class MainController < ApplicationController
  def index
    @products = ThirdPartyProducts.fetch 'Books', 'Ruby on Rails'
  end
end

2 - third_party_products.rb

class ThirdPartyProducts
  def self.fetch category, topic
    Amazon.fetch(category, topic) # + Other.fetch(category, topic)
  end
end

class ThirdPartyProducts::Amazon
  def self.fetch category, topic
    request = Vacuum.new('GB')
    
    # TODO: Move to `config/secrets.yml`
    
    request.configure(
      aws_access_key_id: '',
      aws_secret_access_key: '',
      associate_tag: ''
    )
    
    params = {
      'SearchIndex' => category,
      'Keywords'=> topic,
      'ResponseGroup' => "ItemAttributes,Images"
    }
    
    raw_products = request.item_search(query: params)
    hashed_products = raw_products.to_h

    @products = []
    
    hashed_products['ItemSearchResponse']['Items']['Item'].each do |item|
      product = OpenStruct.new
      product.name = item['ItemAttributes']['Title']
      product.url = item['DetailPageURL']
      product.image_url = item['LargeImage']['URL']
      
      @products << product 
    end
  end
end

3 - index.html.erb

<h1>Products from the Amazon API</h1>
<% if @products.any? %>
  <% @products.each do |product| %>
    <div class="product">
      <%= link_to image_tag(product.image_url), product.url %>
      <%= link_to product.name, product.url %>
    </div>
  <% end %>
<% end %>