slack_channel.rb

require 'httparty'

TOKEN = "xoxp-105525597987-111410440576-176854780516-7dcef01f9a30d7b808a9ebce3248439d"
BASE_URL = "https://slack.com/api/"

class SlackException < StandardError
end

class SlackChannel
  attr_reader :name, :raw_data

  def initialize(data)
    @name = data["name"]
    @raw_data = data
  end

  def send(message)
    # Extra data!
    query_params = {
      "token" => TOKEN,
      "channel" => @name,
      "text" => message,
      "username" => "Roberts-Robit",
      "icon_emoji" => ":robot_face:",
      "as_user" => "false"
    }

    url = "#{BASE_URL}chat.postMessage"
    response = HTTParty.post(url, query: query_params)

    if response["ok"]
      puts "Everything went swell"
    else
      raise SlackException.new(response["error"])
    end
  end

  def self.all
    url = "#{BASE_URL}channels.list?token=#{TOKEN}"
    response = HTTParty.get(url).parsed_response

    if response["ok"]
      channel_list = response["channels"].map do |channel_data|
        self.new(channel_data)
      end

      return channel_list
    else
      raise SlackException.new(response["error"])
    end
  end
end


puts "Welcome to the Slack API Demo"
puts "Here are all the channels"

begin
  channels = SlackChannel.all
rescue SlackException => exception
  puts "Got an error: #{exception}"
  exit
end
channels.each do |channel|
  puts "  #{channel.name}"
end

puts "What channel do you want?"
channel_name = gets.chomp
channel = channels.find do |channel|
  channel.name == channel_name
end

if channel
  puts "What do you want to send?"
  message = gets.chomp
  channel.send(message)

else
  puts "No such channel!"
end