B423_api_demo.rb

require 'json'
require 'open-uri'

# Lets call the github API
url = 'https://api.github.com/users/haumer/gists'

user_serialized = open(url).read
user = JSON.parse(user_serialized)

puts "#{user['name']} - #{user['bio']}"

beers.csv

beers.json

{
  "title": "Great beers",
  "beers": [
    {
      "name": "Edelweiss",
      "appearance": "White",
      "origin": "Austria"
    },
    {
      "name": "Cuvée des Trolls",
      "appearance": "Blond",
      "origin": "Belgium"
    },
    {
      "name": "Choulette Ambrée",
      "appearance": "Amber",
      "origin": "France"
    },
    {
      "name": "Gulden Draak",
      "appearance": "Dark",
      "origin": "Belgium"
    }
  ]
}

beers.xml

<?xml version="1.0" encoding="UTF-8"?>
<beers>
  <title>Great beers</title>
  <beer>
    <name>Edelweiss</name>
    <appearance>White</appearance>
    <origin>Austria</origin>
  </beer>
  <beer>
    <name>Cuvée des Trolls</name>
    <appearance>Blond</appearance>
    <origin>Belgium</origin>
  </beer>
</beers>

csv_demo.rb

require 'csv'

# PARSING CSV
# TODO - let's read/write data from beers.csv
filepath = 'data/beers.csv'

csv_options = { col_sep: ',', quote_char: '"', headers: :first_row }

CSV.foreach(filepath, csv_options) do |row|
  puts "#{row["Name"]} is a #{row["Appearance"]} beer from #{row["Origin"]}"
end

# STORING CSV
csv_options = { col_sep: ',', force_quotes: true, quote_char: '"' }

beers = [
  {
    name: 'Asahi',
    appearance: 'Pale Lager',
    origin: 'Japan'
  },
  {
    name: 'Millier Lile',
    appearance: 'Light Pilsner',
    origin: 'USA'
  }
]

CSV.open(filepath, 'wb', csv_options) do |csv|
  beers.each do |beer|
    csv << [beer[:name], beer[:appearance], beer[:origin]]
  end
end

json_demo.rb

require 'json'

# PARSE JSON
filepath = 'data/beers.json'

serialized_beers = File.read(filepath)

p serialized_beers.class
beers = JSON.parse(serialized_beers)

selected = beers['beers'].each do |beer|
  p beer['origin']
end

# STORE JSON
beers = { beers: [
  {
    name:       'Edelweiss',
    appearance: 'White',
    origin:     'Austria'
  },
  {
    name:       'Guinness',
    appearance: 'Stout',
    origin:     'Ireland'
  }
]}

File.open(filepath, 'wb') do |file|
  file.write(JSON.generate(beers))
end

scraping_demo.rb

require 'open-uri'
require 'nokogiri'

# Let's scrape recipes from http://www.epicurious.com

ingredient = 'cookie'
url = "https://www.bbcgoodfood.com/search/recipes?query=#{ingredient}"

selector = '.teaser-item__title'
# id would be with #id_name

html_file = open(url).read
html_doc = Nokogiri::HTML(html_file)

html_doc.search(selector).each do |recipe|
  p recipe.text.strip
end