add-slack-decomojis.rb

# I'm here: ~/src/github.com/decomoji/slack-reaction-decomoji/scripts/
require 'kimurai'
require 'highline/import'
require 'retryable'
require 'open-uri'
require 'json'

class Spider < Kimurai::Base
  @name = "slack_spider"
  @engine = :selenium_chrome
  @start_urls = ["https://slack.com"]
  @config = {
    user_agent: "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/68.0.3440.84 Safari/537.36",
    before_request: { delay: 4..7 }
  }

  def parse(response, url:, data: {})
    # Ask team name
    Retryable.retryable do
      @team_name = ask('Your slack team name(subdomain): ')
      @url = "https://#{@team_name}.slack.com"
      browser.visit(@url)
      response = browser.current_response

      ## TODO: Need to handle error
      # unless response.css("#signin_form")
      #   logger.error "Not found workspace. Please try again."
      #   raise
      # end
    end

    # Login
    Retryable.retryable do
      ## TODO: Need to handle 2FA
      @email      = ask('Login email: ')
      @password   = ask('Login password(hidden): ') { |q| q.echo = false }

      browser.fill_in "email", with: @email
      browser.fill_in "password", with: @password
      browser.click_on "signin_btn"
      response = browser.current_response

      ## TODO: Need to handle error
      # if response.css("#signin_btn")
      #   logger.error "You entered an incorrect email address or password."
      #   raise
      # end
    end

    # Go to emoji page
    @emoji_url = @url + "/customize/emoji"
    browser.visit(@emoji_url)
    response = browser.current_response

    # Upload decomojis
    @img_dir = File.expand_path(File.dirname(__FILE__) + "/../decomoji/extra")
    files = Dir.glob(@img_dir + "/*.png")
    len = files.length
    emojis = list_emojis
    files.each.with_index(1) do |path, i|
      basename = File.basename(path, '.*')
      logger.info "(#{i}/#{len}) importing #{basename}..."

      # skip if already exists
      if emojis.include?(basename)
        logger.info "(#{i}/#{len}) #{basename} already exists, skip"
        next
      end
      
      begin
        browser.find(:css,
                     'button[data-qa="customize_emoji_add_button"]',
                     wait: 0.1).click
        browser.attach_file "emojiimg", path
        browser.fill_in "emojiname", with: basename
        browser.find(:css,
                     'button[data-qa="customize_emoji_add_dialog_go"]',
                     wait: 0.1).click
      rescue => ex
        ## TODO: Need to handle error more smartly
        logger.warn "Fails to add."
        browser.find(:css,
                     'button[data-qa="sk_close_modal_button"]').click        
        next
      end

      # refresh
      response = browser.current_response
    end
  end
  
  def list_emojis
    ## Create App on Slack -> Bot Token Scopes : "emoji:read"
    token = ask('Token:')
    emoji_url = "https://slack.com/api/emoji.list?token=#{token}"
    JSON.parse(URI.open(emoji_url).read)["emoji"]
  end
end

Spider.crawl!

It's a good script.
A runtime error occurred because there are undefined variables.
The modified parts are as follows.

diff --git a/add-slack-decomojis.rb b/add-slack-decomojis.rb
index 27c6bf4..65d2647 100644
--- a/add-slack-decomojis.rb
+++ b/add-slack-decomojis.rb
@@ -56,6 +56,7 @@ class Spider < Kimurai::Base
     @img_dir = File.expand_path(File.dirname(__FILE__) + "/../decomoji/extra")
     files = Dir.glob(@img_dir + "/*.png")
     len = files.length
+    emojis = list_emojis
     files.each.with_index(1) do |path, i|
       basename = File.basename(path, '.*')
       logger.info "(#{i}/#{len}) importing #{basename}..."

Thx! Fixed.