download_csv.rb

require 'json'
require 'open-uri'
require 'fileutils'

class RevisionGetter

	attr_reader :write_directory, :revisions

	def initialize(args)
		@write_directory = args[:write_dir] || "google_drive_download"
		@revisions = args[:revisions]
		FileUtils.mkdir_p write_directory
	end

	def get_revisions
		revisions.each do |item|
			begin
				user = item["lastModifyingUserName"]
				date = item["modifiedDate"][0...-5]
				# url = item["exportLinks"]["text/csv"]
				url = item["exportLinks"]["application/vnd.openxmlformats-officedocument.spreadsheetml.sheet"]
				puts "Writing file: #{date+"-"+user}.xlsx"
				download_and_save(url, date+"-"+user)
			rescue
				puts "error occured, continuing..."
			end
		end
	end

	def download_and_save(file_url, file_out)
		open(write_directory+'/'+file_out+".xlsx", 'wb') do |file|
			file << open(file_url).read
		end
	end
end


test_response = JSON.load(File.read('test.json'))

revGetter = RevisionGetter.new(write_dir: "langtang_spreadsheets", revisions: test_response['items'])
revGetter.get_revisions