czarneckid

Zero downtime deploys with unicorn + nginx + runit + rvm + chef

Below are the actual files we use in one of our latest production applications at Agora Games to achieve zero downtime deploys with unicorn. You've probably already read the GitHub blog post on Unicorn and would like to try zero downtime deploys for your application. I hope these files and notes help. I am happy to update these files or these notes if there are comments/questions. YMMV (of course).

Other application notes:

• Our application uses MongoDB, so we don't have database migrations to worry about as with MySQL or postgresql. That does not mean that we won't have to worry about issues with the database with indexes being built in MongoDB or what have you.
• We use capistrano for deployment.

Salient points for each file:

vjt

import File.expand_path(File.dirname(__FILE__) + '/schema_format.rb')

namespace :db do
  # Define PG environment utility methods
  task :pg_env => :environment do
    def pg_get_config
      ActiveRecord::Base.configurations.fetch(Rails.env).tap do |config|
        ENV['PGHOST']     = config['host'].to_s     if config.key?('host')
        ENV['PGPORT']     = config['port'].to_s     if config.key?('port')
        ENV['PGPASSWORD'] = config['password'].to_s if config.key?('password')

monde

App.DelayedTextField = Ember.TextField.extend({

  // FIXME
  // double check that init in Ember.TextSupport / Ember.TextSupport
  // isn't handling this.on("paste"...) and the internal variable is still
  // this._elementValueDidChange
  init: function() {
    this.on("propertychange", this, this._elementValueDidChange);
    this.on("keyup", this, this._elementValueDidChange);
    this.on("input", this, this._elementValueDidChange);

ryanb

My issues with Modules

In researching topics for RailsCasts I often read code in Rails and other gems. This is a great exercise to do. Not only will you pick up some coding tips, but it can help you better understand what makes code readable.

A common practice to organize code in gems is to divide it into modules. When this is done extensively I find it becomes very difficult to read. Before I explain further, a quick detour on instance_eval.

You can find instance_eval used in many DSLs: from routes to state machines. Here's an example from Thinking Sphinx.

class Article < ActiveRecord::Base

tsmango

require 'bundler/capistrano'

# This capistrano deployment recipe is made to work with the optional
# StackScript provided to all Rails Rumble teams in their Linode dashboard.
#
# After setting up your Linode with the provided StackScript, configuring
# your Rails app to use your GitHub repository, and copying your deploy
# key from your server's ~/.ssh/github-deploy-key.pub to your GitHub
# repository's Admin / Deploy Keys section, you can configure your Rails
# app to use this deployment recipe by doing the following:

topfunky

Changes in Express 3.0 Templates

Related: PeepCode Full Stack Node.js screencast (an included code sample works with Express 3.0).

There are several syntax changes in Express 3.0. They do require modifications to your code, but they aren't too complicated.

The biggest change is that Express templates now use Django style inheritance rather than ERB/Rails style automatic layouts.

Summary

Tronix117

#!/bin/bash

# Configuration (to edit)
RCPATH=~/.bashrc
PROJECT_DIRECTORY=~/Sites/myproject # project directoy (if it doesn't exist, the project will be installed here)
PROJECT_GIT_REPOSITORY='git@github.com:myname/myproject.git' # git repository of the project
DBPASS='123456' # root pass

# Your current Rails configuration (fill it with config/database.yml)
RAILS_BASE='myproject_dev'

mshafrir

{
    "AL": "Alabama",
    "AK": "Alaska",
    "AS": "American Samoa",
    "AZ": "Arizona",
    "AR": "Arkansas",
    "CA": "California",
    "CO": "Colorado",
    "CT": "Connecticut",
    "DE": "Delaware",

dbainbridge

/**
 * Module dependencies.
 */

var express = require('express')
  , routes = require('./routes')
  , http = require('http');

var app = express();
var server = app.listen(3000);

elijahmanor

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