export_slack_emojis.rb

require 'json'
require 'open-uri'

Dir.mkdir('emojis') unless Dir.exist?('emojis')

number = Integer(ARGV[0]) || 10
# assuming you have numbered the files correctly, loops through each
(1..number).each do |i|
  file = File.open("emoji#{i}.json")
  data = JSON.load(file)
  # we only care about the data within "emoji" key
  data["emoji"].each do | emoji |
    begin
      url = emoji["url"]
      file_type = url.split(".").last
      file_name = emoji["name"] + "." + file_type
      # if you've done this for multiple slacks, you might have duplicates
      if File.file?("emojis/#{file_name}")
        puts "skipping #{file_name}, url: #{url}"
        next
      end
      puts "writing #{file_name}"
      File.write "emojis/#{file_name}", open(url).read
    rescue
      puts "Error downloading: #{emoji["url"]}"
      next
    end
  end
end