slack_bot.rb

require 'json'
require 'uri'
require 'net/https'
class Slack
  def initialize(settings)
    @host = settings["host"]
    @endpoint = settings["endpoint"]
    @token = settings["token"]
  end
  def send_message(message, username="kussan-bot", icon_emoji=":kussan:", channel="#develop")
    data = {
      type: "message",
      subtype: "bot_message",
      text: message,
      username: username,
      icon_emoji: icon_emoji,
      channel: channel,
    }
    https = Net::HTTP.new(@host, 443)
    https.use_ssl = true
    https.verify_mode = OpenSSL::SSL::VERIFY_NONE
    https.start do |https|
      https.post(sprintf("%s%s", @endpoint, @token), "payload=#{data.to_json}")
    end
  end
end

# yaml sample
# slack:
#   token: "TOKEN"
#   host: "YOUR.slack.com"
#   endpoint: "/services/hooks/incoming-webhook?token="
settings = YAML.load_file('config/settings.yml')
slack = Slack.new(settings["slack"])
slack.send_message('ﾁﾝﾁﾝﾁﾝﾁﾝﾁﾝﾁﾝﾁﾝﾁﾝﾁﾝﾁﾝﾁﾝﾁﾝﾁﾝﾁﾝﾁﾝﾁﾝ', 'おじさんbot', ':ojisan:', '#general')