Use DataCite API to complete Old URL column for ISTL journal migration

istl_url.rb

require 'net/http'
require 'json'
require 'csv'

CSV.open('istl_url.csv', 'wb') do |csv|
  csv << ['doi', 'url']

  File.open("istl_doi.txt") do |f|
    f.each_line(chomp: true) do |doi|
      source = URI.parse("https://api.datacite.org/dois/#{doi}")
      resp = Net::HTTP.get_response(source) 
      data = resp.body
      result = JSON.parse(data).to_h
      csv << [result['data']['id'], result['data']['attributes']['url']] # needs error handling, I'm manually editing istl_doi.txt to keep this going
    end
  end
end