Learning Deployment - The Rails Way

And so I was up to Chapter 16: Task K - Deployment and Production of Agile Web Development with Rails 2 weeks ago. This is the last chapter of the hands on tutorial.

I was very excited arriving to this chapter as I was curious to see how Rails handles deployment. I couldn’t wait to get my hands dirty with setting up and installing parts that will hopefully form a smooth and automated deployment process.

Back on tutorial itself, the application was run on the standard Rails setup for development ie: WEBrick (Ruby’s own application server) and SQLlite for the database. Now, in this chapter, to make it more a real world like, we would deploy the application on Apache and MySQL.

It wasn’t exactly smooth sailing process, in this post, I will try to describe the problems that I encountered and how I solved (or ignored) them as well as questions that I have. Plus a short description on my failed attempt to deploy to Heroku (boo!).

If you follow the example in the book - the aim of this exercise is to actually “mimic” a production deployment - only we are not deploying our app remotely but rather locally.

First off - I did an install of Phusion Passenger - I am not sure what it is (a server or a connector?) - but it allows you to run Ruby on Rails on an Apache server.

Then we need to change Apache configuration. First of we need to “connect” Apache to Passenger - this is done by adding the following lines on my apache2.conf file.

LoadModule passenger_module /home/felixt/.rvm/gems/ruby-1.9.2-p180/gems/passenger-3.0.7/ext/apache2/mod_passenger.so
PassengerRoot /home/felixt/.rvm/gems/ruby-1.9.2-p180/gems/passenger-3.0.7
PassengerRuby /home/felixt/.rvm/wrappers/ruby-1.9.2-p180/ruby

Then we need to add our “production” site on Apache virtual host - which happens to be on /default/000 on my installation

<VirtualHost *:80>
ServerName movie-depot.production.passionate.int

RailsEnv production

DocumentRoot /home/felixt/prj/movie-depot-production/public
<Directory /home/felixt/prj/movie-depot-production/public>
AllowOverride all
Options -MultiViews
</Directory>
</VirtualHost>

Noticed the RailsEnv production line there? That’s neat - that’s how Passenger knows which application it’s serving, other than that it’s a vanilla Apache virtual host entry.

Restart Apache - browse to the site and I got a database error. Sure enough I haven’t created my production database.

I setup the deployment script as described in the book. My deployment script is a little bit different - rather than checking out from local git server, I actually made it so that it checked out from the application Github repository.

And when I ran the deploy setup, I got the following error:

* executing `deploy:setup'
* executing "sudo -p 'sudo password:
.....
servers: ["felixt", "movie-depot-prod.passionate.int"]
Password:
connection failed for: felixt (SocketError: getaddrinfo: Name or service not known)

Umh ok, what does SocketError: getaddrinfo mean?

Since I am running Ubuntu 10.04 - here is the command to get SSH server installed… Hm on the second thought, I am too lazy to type - it’s been taking few days now to get this post up.. So just go this blog post:Basic SSH Setup On Ubuntu 10.04 Lucid Lynx Using OpenSSH Server - I pretty much followed the instruction there and it worked for me.

-----> Gemfile detected, running Bundler version 1.0.7
       Unresolved dependencies detected; Installing...
       Using --without development:test
       Some gems seem to be missing from your vendor/cache directory.
       Could not find activesupport-3.0.5.rc1 in any of the sources
       FAILED: http://devcenter.heroku.com/articles/bundler
 !     Heroku push rejected, failed to install gems via Bundler

I will have to look into it later - or ask the Heroku support (apparently they have a very good customer support there..).

The next step for me is to get Rails installed on my VivioTech CentOS VPS.

Again it feels nice how gems makes installing dependencies super easy. Integration between Ruby and Apache with Passenger looks very easy as well.

Deployment with Capistrano - looks to be the trickiest and somewhat limited (only supporting SSH). The deploy.rb (and recipes?) does seem to be less verbose compared to Ant script for example. I don’t know.. this is just an initial impression, I have always used Ant for ColdFusion deployment and I don’t see Capistrano offers anything that Ant doesn’t have (yet).