ZenLinux Blog

I deployed a Ruby on Rails application using Vlad the Deployer for the first time today. Vlad is a much, much simpler alternative to Capistrano, which I’ve also used.

However, the process wasn’t as smooth as it could have been. I ran into the following issues that required some digging:

1. My subversion repository is accessed via an https web server, which happens to use a self-signed SSL certificate. The svn program prompts you to verify and save this certificate the first time you perform a checkout. Vlad hung on this prompt until I logged into my deployment server as the user and manually completed a checkout from the repository.

2. My subversion repository is also password-protected using HTTP authentication. Vlad apparently doesn’t know how to deal with this, as I couldn’t find any documented variables to set an svn username or password. However, I could override the subversion command, and add switches for the username and password in my deploy.rb file:

set :svn_cmd, "svn --username=\"USERNAME\" --password=\"PASSWORD\""

3. The vlad:start task runs apachectl to give apache a kick after starting up mongrel. That binary was not in my user’s path, so I had to edit the user’s .bashrc file to add /usr/sbin to the $PATH environment variable. Second, the apachectl command needs to be run with root privileges, and Vlad seems to have no knowledge of sudo. To fix this, I was going to override the vlad:start task, and started poking around the gem sources to see how the original task was defined. That’s when I noticed that it sets the variable :web_command internally, so I was instead able to override that with another addition to my deploy.rb file:

set :web_command, "sudo apachectl"

These weren’t a huge deal, but that’s only because I’ve dealt with Capistrano and have an idea of what variables should exist to configure these kinds of options. I’m liking Vlad a lot.

In fact, I’m pretty sure for October I’ll be doing a presentation for NHRuby.org on Vlad the Deployer.