Hi, I’m Josh Symonds

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Sidekiq + Houston: Persistent Apple Connection Pooling

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I updated the code here based on my production experiences with it in a new post, Sidekiq + Houston: Production Ready. Check it out after reading this article.

Having not updated rapnd in a good long while, I was looking for well-supported, up-to-date solution for persisting long-running connections to Apple’s push notification service through a worker. I didn’t run into anything offhand, and also haven’t posted a helpful code snippet in awhile, so this is how I connected Houston and Sidekiq to Apple’s Push Notification service.

From Houston’s documentation, we can easily set up a persistent connection with code like this:

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uri, certificate = if Rails.env.production?
  [
    Houston::APPLE_PRODUCTION_GATEWAY_URI,
    File.read("/path/to/production_key.pem")
  ]
else
  [
    Houston::APPLE_DEVELOPMENT_GATEWAY_URI,
    File.read("/path/to/development_key.pem")
  ]
end

connection = Houston::Connection.new(uri, certificate, nil)
connection.open

Maintaining a persistent connection pool with Sidekiq workers is easy thanks to Sidekiq’s integration with Connection Pool. We can set that up fairly easily like so:

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APN_POOL = ConnectionPool.new(:size => 2, :timeout => 300) do
  # above code
end

I didn’t want more than two connections since that should suffice for initial load; and a timeout of 5 minutes seemed reasonable enough for me. Ultimately, my worker ended up looking like this:

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class NotifierWorker
  include Sidekiq::Worker

  APN_POOL = ConnectionPool.new(:size => 2, :timeout => 300) do
    uri, certificate = if Rails.env.production?
      [
        Houston::APPLE_PRODUCTION_GATEWAY_URI,
        File.read("/path/to/production_key.pem")
      ]
    else
      [
        Houston::APPLE_DEVELOPMENT_GATEWAY_URI,
        File.read("/path/to/development_key.pem")
      ]
    end

    connection = Houston::Connection.new(uri, certificate, nil)
    connection.open

    connection
  end

  def perform(message, token)
    APN_POOL.with do |connection|
      notification = Houston::Notification.new(device: token)
      notification.alert = message
      connection.write(notification.message)
    end
  end

end

Josh Symonds performs devops and server wrangling on cloud-scale infrastructures, deploys amazing web applications with Ruby on Rails, and creates awesome iOS apps with Objective-C and RubyMotion. He is founder and CTO of Symonds & Son, a development shop focused on quality and excellence.

Josh Symonds