Rails app deployment

I have written a few Rails applications, but I couldn't have implemented anything useful for my day-to-day use. At least one of these applications I wrote seems usable, but I found Rails app deployment was the blocking factor. I wrote a very simple app and just focused on Rails app deployment today. It turned out that there are enough things to overcome and that's why I couldn't complete my projects.

Picking a production configuration

It is nice for Rails to have easy-to-use application servers such as Mongrel or Webrick. For a low traffic site like mine, it should be okay in terms of performance. However, I have existing python CGIs and contents may not run. I need to create a hybrid envornment to serve both legacy CGIs and new Rails apps. There are a bunch of possibilities, and I picked apache + Phusion Passenger because 1) the existing site runs apache and 2) it seems to be one of the good choices in 2008-2009.

Phusion Passenger installation on Gentoo Linux

Installation of Phusion Passenger was simple, but apache configuration was not. This is not Passenger's fault by the way. Passenger is an Apache loadable module. Apache needs to load it when it starts. Gentoo Linux stores module configurations in /etc/apache2/modules.d (not /etc/modules.d!). I created /etc/apache2/99_passenger_gaku_net.conf I had a couple of erros here and here's how I debugged.

• I had wrong PassengerRuby path. Passenger didn't spit error. Just type the Ruby path and make sure it runs a Ruby interpretor.
• Use PassengerLogLevel directive for debugging. PassengerLogLevel 1
• I enabled Apache's /server-info handler by opening it up to everyone temporalily. To do this, modify /etc/apache2/modules.d/00_mod_info.conf. Then, http://www.gaku.net/server-info shows useful info on Apache, and it should have mod_passenger.c in the page when the module was properly loaded. (/server-info is turned off now).

Installing a Rails app

As I have existing content on my site, I decided to give /isbn to my test Rails app. Other URI will be served by existing configuration. It can be achieved by adding a following line in my vhost configution in /etc/apache2/vhost.d/.

RailsBaseURI /isbn

The filesystem directory /web/isbn needs to point the Rails app's public directory. I created a symboic link from my web directory. My error here was using a wrong directive. There is RukeBaseURI. I needed to use RailsBaseURI.

Bay Area OSM on my Garmin 60csx

I've been using an OSM map made by cloudmead for last couple of days, but it is hard to read under the sun, because streets are rendered in light gray. I've decided to generate one. I used the bounding box of bbox=-122.496,37.017,-121.807,37.84297 to cover most of the San Francisco Bay area. It roughly covers San Francisco to San Jose. It doesn't cover Northern part of the Bay area as I don't go there often.

wget -O down.osm http://www.informationfreeway.org/api/0.5/map?bbox=-122.496,37.017,-121.807,37.84297

The one above no longer works in 2010. Try the following one:

wget -O down.osm http://www.informationfreeway.org/api/0.6/map?bbox=-122.496,37.017,-121.807,37.84297

java -Xmx512M -jar mkgmap.jar --gmapsupp down.osm

The downloaded data was 168MB. .img file genereated by mkgmap is just about 3MB and it is quite impressive. The time to convert was only 30 secs or so.

portage conflicts with bash

I haven't updated Gentoo Linux for long time. When I did emerge portage, it was blocked with bash. However, the latest bash needed portage too. Because bash and portage depends on each other, it can't be resolved in one shot. The basic strategy of solving these dependencies is to update bash to certain version, update portage and update bash to the latest. Look at /usr/portage/app-shells/bash, I have following packages: -rw-r--r-- 1 root root 3408 Mar 23 2006 bash-2.05b-r11.ebuild -rw-r--r-- 1 root root 5065 Jun 25 2007 bash-3.0-r12.ebuild -rw-r--r-- 1 root root 4613 Jun 25 2007 bash-3.0-r13.ebuild -rw-r--r-- 1 root root 4724 Jun 25 2007 bash-3.0-r14.ebuild -rw-r--r-- 1 root root 4601 Feb 27 2007 bash-3.1_p17.ebuild -rw-r--r-- 1 root root 5190 Feb 9 2008 bash-3.2_p17-r1.ebuild -rw-r--r-- 1 root root 5653 Jun 1 2008 bash-3.2_p33.ebuild -rw-r--r-- 1 root root 6156 Aug 24 10:35 bash-3.2_p39.ebuild -rw-r--r-- 1 root root 6156 Nov 20 12:57 bash-3.2_p48.ebuild So, I picked 3.2_p17-r1 as the intermediate version. # emerge -1 =bash-3.2_p17-r1 # emerge -1 portage # emerge bash Yay!

I have a lighttpd + Ruby on Rails via FCGI installation and I started to see 500 - Internal Server Error from lighttpd when I accessed my rails application.

2008-11-29 01:15:11: (log.c.75) server started
2008-11-29 01:15:22: (mod_fastcgi.c.1743) connect failed: Connection refused on unix:/tmp/ruby-railsapp.fastcgi-0
2008-11-29 01:15:22: (mod_fastcgi.c.2912) backend died; we'll disable it for 5 seconds and send the request to another backend instead: reconnects: 0 load: 1
2008-11-29 01:15:23: (mod_fastcgi.c.2471) unexpected end-of-file (perhaps the fastcgi process died): pid: 2068 socket: unix:/tmp/ruby-railsapp.fastcgi-0
2008-11-29 01:15:23: (mod_fastcgi.c.3234) child exited, pid: 2068 status: 1
2008-11-29 01:15:23: (mod_fastcgi.c.3281) response not received, request sent: 867 on socket: unix:/tmp/ruby-railsapp.fastcgi-0 for /dispatch.fcgi , closing connection

There's no error in log/fastcgi.crash.log nor log/development.log of my Rails installation. It appeared that public/dispatch.fcgi was called and failed. I put a bunch of fprintf-equivarent and found out that the line with

require File.dirname(__FILE__) + "/../config/environment".

was the line where it failed. I needed to know how it failed, and I put code to dump the stack trace:

begin
require File.dirname(__FILE__) + "/../config/environment"
rescue Exception => exception
File.open('/tmp/a.log', 'a') do |f|
  f.puts exception.class.name + ":" + exception.message
  f.puts exception.backtrace.join("\n")
end
end

and it gave me some clue:

SystemExit:exit /Users/gaku/ror/iphone/public/../config/boot.rb:65:in `exit' /Users/gaku/ror/iphone/public/../config/boot.rb:65:in `load_rails_gem' /Users/gaku/ror/iphone/public/../config/boot.rb:53:in `load_initializer' /Users/gaku/ror/iphone/public/../config/boot.rb:38:in `run' /Users/gaku/ror/iphone/public/../config/boot.rb:11:in `boot!' /Users/gaku/ror/iphone/public/../config/boot.rb:109 /Users/gaku/ror/iphone/public/../config/environment.rb:11:in `require' /Users/gaku/ror/iphone/public/../config/environment.rb:11 /Users/gaku/ror/iphone/public/dispatch.fcgi:28:in `require' /Users/gaku/ror/iphone/public/dispatch.fcgi:28

It failed in load_rails_gem and there was an attempt to dump error message to stderr, but FCGI didn't spit the message anywhere. The message was:

$stderr.puts %(Missing the Rails #{version} gem. Please `gem install -v#{version} rails`, update your RAILS_GEM_VERSION settingin config/environment.rb for the Rails version you do have installed, or comment out RAILS_GEM_VERSION to use the latest version installed.)

I have rails 2.2.2 gem installed, and I updated RAILS_GEM_VERSION variable in config/environment.rb to 2.2.2. However, in fact, the code tried to run

gem 'rails', '2.2.2'

and threw Gem::LoadError. I need to dig deeper. I put another stack trace code to the Gem::LoadError handler and it revealed another trace:

Gem::LoadError:Could not find RubyGem activesupport (= 2.2.2) /opt/local/lib/ruby/site_ruby/1.8/rubygems.rb:636:in `report_activate_error' /opt/local/lib/ruby/site_ruby/1.8/rubygems.rb:141:in `activate' /opt/local/lib/ruby/site_ruby/1.8/rubygems.rb:165:in `activate' /opt/local/lib/ruby/site_ruby/1.8/rubygems.rb:164:in `each' /opt/local/lib/ruby/site_ruby/1.8/rubygems.rb:164:in `activate' /opt/local/lib/ruby/site_ruby/1.8/rubygems.rb:49:in `gem' /Users/gaku/ror/iphone/public/../config/boot.rb:62:in `load_rails_gem' /Users/gaku/ror/iphone/public/../config/boot.rb:53:in `load_initializer' /Users/gaku/ror/iphone/public/../config/boot.rb:38:in `run' /Users/gaku/ror/iphone/public/../config/boot.rb:11:in `boot!' /Users/gaku/ror/iphone/public/../config/boot.rb:123 /Users/gaku/ror/iphone/public/../config/environment.rb:11:in `require' /Users/gaku/ror/iphone/public/../config/environment.rb:11 /Users/gaku/ror/iphone/public/dispatch.fcgi:28:in `require' /Users/gaku/ror/iphone/public/dispatch.fcgi:28

It was not a failure to load rails 2.2.2 gem, but it failed to load underlying gem called activesupport. It says "Could not find RubyGem activesupport (= 2.2.2)". It looked to me that I also have activesupport 2.2.2 according to my gem list --local command. However, when I run gem uninstall activesupport, there's an strange error:

kvant-2% sudo gem uninstall activesupport ERROR: While executing gem ... (Gem::InstallError) Unknown gem activesupport >= 0

So, I reinstalled activesupport anyway and this fixed the problem. It looks like the cause of the problem was broken activesupport gem installation. It should have happened during my upgrade of Rails from 2.1 to 2.2. I don't know how it happen though. Lessons

• lighttpd's "child exited with status 1 /Users/gaku/ror/iphone/public/dispatch.fcgi" actually means Ruby fcgi script exit with status 1. Rails framework has such code.
• Stack trace is easy and informative in Ruby.
• gem installation could be broken. gem uninstall/install may help.

Bacce in San Francisco

This is a Italian restaurant in North beach.
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Eclipse download maze

I am trying out a few JavaScript IDEs and JSEclipse needs Eclipse. So, I went to Eclipse.org to install Eclipse. There's a big button saying "Download Eclipse", and I was taken to Downloads page. It was simple before, but now it is complicated. There are several Eclipse packages, as well as "Third Party Distros". Also, there's an ad saying "eclipse europa". What I need is something called eclipse-sdk, but it is not there. It is pretty confusing. There's no how to pick a right package, nor description of distros. I couldn't know what Eclipse Classic means. The download section seems better to be fixed.