Twitch cli to check if channel is online without accessing browser or receive a push notification

twitch_channel_current_in_live.rb

# frozen_string_literal: true

require 'faraday'
require 'json'
require 'logger'
require 'oga'
require 'pastel'

module Twitch
  module PageLoader
    private

    def page
      @page ||= Faraday.get(@url)
    end
  end

  module PageParser
    private

    def dom
      @dom ||= Oga.parse_html(page.body || '') if page.success?
    end
  end

  class Channel
    include PageLoader
    include PageParser

    attr_reader :url, :name

    def initialize(name)
      @name = name
      @url = "https://www.twitch.tv/#{name}"
    end

    def self.open(name)
      new(name)
    end

    def self.from_url(url)
      new(url.split('/').last)
    end

    def live?
      payload.dig(0, :publication, :isLiveBroadcast) || false
    end

    def payload
      @payload ||=
        begin
          raw = dom.css('script[type="application/ld+json"]').first&.text || '{}'
          JSON.parse(raw, symbolize_names: true)
        end
    end
  end
end

# USAGE:
channels = %w[
  alanzoka alexisdino mrfalll calango galaxyyk
]


def status_description_for(channel)
  p = Pastel.new

  time = p.inverse("[#{Time.now}]")
  title = "#{channel.name} ( #{channel.url} )"
  status = channel.live? ? p.green('live') : p.red('offline')

  "#{time} Channel #{title} is #{status}!"
end

channels.each do |channel_name|
  channel = Twitch::Channel.open(channel_name)
  puts status_description_for(channel)
end


# SPEC
exit unless ENV['SPECS'] == 'true'
require 'rspec/autorun'

RSpec.describe Twitch::Channel do
  describe '.from_url' do
    subject(:instance) { described_class.from_url('https://www.twitch.tv/alanzoka') }

    it 'returns a channel object' do
      expect(instance).to be_a(described_class)
    end
  end

  describe '.open' do
    subject(:instance) { described_class.open('alanzoka') }

    it 'returns a channel object' do
      expect(instance).to be_a(described_class)
    end

    it 'sets the channel name' do
      expect(instance.name).to eq('alanzoka')
    end

    it 'sets the channel url' do
      expect(instance.url).to eq('https://www.twitch.tv/alanzoka')
    end

    it 'sets the channel payload' do
      expect(instance.payload).to include(kind_of Hash)
    end
  end

  describe '#live?' do
    context 'when the channel is live' do
      it 'returns true' do
        expect(described_class.open('alanzoka').live?).to eq(true)
      end
    end

    context 'when the channel is offline' do
      it 'returns false' do
        expect(described_class.open('carolschmitt').live?).to eq(false)
      end
    end

    context 'when the channel not exists' do
      it 'returns false' do
        expect(described_class.open('xundachannelmagicunicorn').live?).to eq(false)
      end
    end
  end
end