I swore I wouldn't

I received the error “The change you wanted was rejected” after I moved a rails app from one host to another.

Looking into the log file, the following error appears:

ActionController::InvalidAuthenticityToken (ActionController::InvalidAuthenticityToken):
/usr/lib/ruby/1.8/mongrel/rails.rb:76:in `process'
/usr/lib/ruby/1.8/mongrel/rails.rb:74:in `synchronize'
/usr/lib/ruby/1.8/mongrel/rails.rb:74:in `process'
/usr/lib/ruby/1.8/mongrel.rb:159:in `process_client'
/usr/lib/ruby/1.8/mongrel.rb:158:in `each'
/usr/lib/ruby/1.8/mongrel.rb:158:in `process_client'
/usr/lib/ruby/1.8/mongrel.rb:285:in `run'
/usr/lib/ruby/1.8/mongrel.rb:285:in `initialize'
/usr/lib/ruby/1.8/mongrel.rb:285:in `new'
/usr/lib/ruby/1.8/mongrel.rb:285:in `run'
/usr/lib/ruby/1.8/mongrel.rb:268:in `initialize'
/usr/lib/ruby/1.8/mongrel.rb:268:in `new'
/usr/lib/ruby/1.8/mongrel.rb:268:in `run'
/usr/lib/ruby/1.8/mongrel/configurator.rb:282:in `run'
/usr/lib/ruby/1.8/mongrel/configurator.rb:281:in `each'
/usr/lib/ruby/1.8/mongrel/configurator.rb:281:in `run'
/usr/lib/ruby/1.8/mongrel/command.rb:212:in `run'

Rendering /vol/sites/site/public/422.html (422 Unprocessable Entity)


Some further investigation revealed that there was an issue with how rails 2.3.8 was handling cookies.  I stumbled upon the following fix at https://rails.lighthouseapp.com/projects/8994/tickets/4690.

I used Ken Collins’ fix of adding his mongrel.rb (http://gist.github.com/471663) to config/initializers and now all is well.