Parsing&Storing

API_demo.rb

require 'json'
require 'open-uri'

# Documentation - GitHub API
# https://developer.github.com/v3/
url = 'https://api.github.com/users/ssaunier' # endpoint of Github API

# We open & read what is returning the API call
user_serialized = open(url).read # is a STRING

user = JSON.parse(user_serialized) # is a HASH ( JSON.parse(...) )

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

CSV_demo.rb

require 'csv'

filepath    = 'beers.csv'

# headers: :first_row => transform each row from _ARRAY_ to _HASH_
csv_options = { col_sep: ',', quote_char: '"', headers: :first_row }

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

CSV_storing.rb

require 'csv'

filepath    = 'data/new_beers.csv'
csv_options = { col_sep: ',', force_quotes: true, quote_char: '"' }

beers = [
  {name: "Asahi", appereance: "Lager", origin: "Japan"},
  {name: "Guinness", appereance: "Stout", origin: "Ireland"}
]

CSV.open(filepath, 'wb', csv_options) do |csv| # "WB" => overwrite the entire file
  csv << ['Name', 'Appearance', 'Origin'] # HEADER
  beers.each do |beer| # For each beer (HASH) we want to create an Array and inject into CSV
    csv << [beer[:name], beer[:appereance], beer[:origin]] # We can use symbol cause we are inside Ruby
  end
end

JSON_parsing.rb

require 'json'

filepath = 'data/beers.json'

serialized_beers = File.read(filepath) # is a STRING

beers = JSON.parse(serialized_beers) # is a HASH

#       _HASH__ARRAY_HASH_
p beers["beers"][1]["name"]

JSON_storing.rb

require 'json'

filepath = "data/new_beers.json"

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

File.open(filepath, 'wb') do |file| # |file| => it's the entire file and we want to write in it
  file.write(JSON.generate(beers)) # JSON.generate will return a serialize obj (STRING)
end

scraping.rb

require 'open-uri' # OPEN a Web page
require 'nokogiri' # help us to query the HTML nodes

ingredient = 'chocolate'
url = "http://www.letscookfrench.com/recipes/find-recipe.aspx?s=#{ingredient}"

html_file = open(url).read # serialize the website (STRING)
html_doc = Nokogiri::HTML(html_file) # for each node (h1 - p - div etc) create a Nokogiri Obj


# .search is a Nokogiri method that allow us to search, inside HTML, for nodes using CSS Selector
#                   PARENT       CHILD
html_doc.search('.m_titre_resultat a').each do |element|
  puts element.text.strip
  puts element.attribute('href').value
end