Get Your Ass to 1.9!

You already know that you _should_ be running Ruby 1.9, why aren't you? This is how New Relic upgraded our big-ass, five year old Rails 2.3 app to Ruby 1.9.

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1. GET YOUR ASS TO 1.9! @nicbenders @ralphbod http://nicbenders.com/ruby-19/
2. GET YOUR ASS TO 1.9! @nicbenders @ralphbod http://nicbenders.com/ruby-19/
6. Ruby 1.9 has been out since 2009 (Ruby 2.0 is even out now) Ruby 1.8 will reach EOL in June REE has already reached EOL
7. 0 3750 7500 11250 15000 1.8.6 1.8.7 1.9.2 1.9.3 2.0.0
8. The New Relic App (as of mid-2012) 5 year old codebase 70,000 "Code LOC" and 59,000 "Test LOC" Rails 2.3.14 (started as Rails 1.2.3) REE-1.8.7-2010.02
9. Putting it off Rearchitecting the app first Do it all in a big spike! Have a ruby_19 branch STUPID THINGS WE TRIED
10. Do EVERYTHING on master Setup a CI job for it Start with your smaller apps THE BIG IDEA
11. Be on latest Rails 2.3 or newer Use rbenv / rvm everywhere You already use Bundler, right? Decent test coverage (50% is ok) THE FOUNDATION
12. Getting the test suite to run Upgrade obsolete 3rd party libs THE HARD PART
13. Every commit is run both ways Slowly burn-down the failures (This took us several months) THE GRIND
14. platforms :ruby_19 do gem 'debugger' gem 'crypt19' end platforms :ruby_18 do gem 'ruby-debug' gem 'utility_belt' gem 'fastercsv' gem 'crypt', '1.1.4', :require => nil end
15. # Rails 2.3 did not get along with Ruby 1.9.3 until we did this # See - http://bit.ly/WPAj7a if ::RUBY_VERSION.split('.')[0,3] == ['1','9','3'] MissingSourceFile::REGEXPS.push( [/^cannot load such file -- (.+)$/i, 1] ) end
16. # Prevent accidentally calling #[] on a number [Fixnum, Bignum].each do |k| k.class_eval do def [](*args) raise NoMethodError, "Calling #[] on numbers is wrong." end end end
17. # Use to_sym to ensure that you always have a # symbol in 1.8 or 1.9 instance_methods.map(&:to_sym).include?(:connection)
18. require "csv" # In Ruby 1.8, the library is called FasterCSV, # in 1.9 it's just CSV. So use some constant tricks # to make sure it's always "CSV" for us if CSV.const_defined? :Reader # Ruby 1.8 compatible require 'fastercsv' Object.send(:remove_const, :CSV) CSV = FasterCSV else # CSV is now FasterCSV in ruby 1.9 end
19. --- a/script/server +++ b/script/server @@ -1,3 +1,3 @@ #!/usr/bin/env ruby -require File.dirname(__FILE__) + '/../config/boot' +require File.expand_path('../../config/boot', __FILE__) require 'commands/server'
20. Mongrel Ordered Hashes Regex changes Encodings Enumerable String Lambda Arity
21. Local dev environment first Then each "Staging" env Practice the roll-back plan STARTING THE DEPLOY
22. Roll out servers one-by-one Have extra capacity available Be patient! THE BIG DAY
24. Rotate the knowledge Make it easy to test both locally Background jobs were un-tested THINGS TO DO BETTER
25. Changing the wheels on the bus at 80 mph: upgrading to Rails 3 on an active master branch Andrew Bloomgarden and Julian Giuca
26. JOIN THE TEAM newrelic.com/about/jobs