Test that waits for pub/sub message before asserting.

pub_sub_test.rb

require 'minitest'
require 'minitest/autorun'
require 'minitest/pride'

require 'redis'
require 'sidekiq'

class ThingWorker
  include Sidekiq::Worker

  def perform(message)
    puts message
  end
end
require 'sidekiq/testing'

class ThingListener
  def redis
    redis ||= Redis.new(:timeout => 10)
  end

  def initialize
    puts "redis is #{redis.connected?} connected?"
    redis.subscribe('things') do |on|
      on.subscribe do |channel, s|
        $subscribed = true
        puts "Subscribed to #{channel} with #{s} subscription(s)"
      end

      on.unsubscribe do |channel, s|
        puts "Unsubscribed to #{channel} with #{s} subscription(s)"
      end

      on.message do |channel, message|
        $message = true
        puts "Received message #{message}"
        ThingWorker.perform_async(message)
      end
    end
  end
end

class FakeRedisTest < MiniTest::Test

  def redis
    redis ||= Redis.new(:timeout => 10)
  end

  def setup
    $message = false
    $subscribed = false
    @t1 = Thread.new do
      ThingListener.new
    end
  end

  def wait_for_subscription
    return if $subscribed
    timeout = 10
    loop do
      puts "waiting for subscription #{$subscribed} (timeout in #{timeout})"
      timeout = timeout - 1
      sleep 1
      if $subscribed || timeout == 0
        break
      end
    end
  end

  def wait_for_message
    return if $message
    timeout = 10
    loop do
      puts "waiting for message #{$message} (timeout in #{timeout})"
      timeout = timeout - 1
      sleep 1
      if $message || timeout == 0
        break
      end
    end
  end

  def test_publish
    wait_for_subscription
    redis.publish('things', "Hello World")
    wait_for_message
    assert_equal 1, ThingWorker.jobs.size
  end

  def teardown
    @t1.exit
  end
end