问题
I am working on Ubuntu 10.04 LTS, Lucid Lynx, have installed Ruby on Rails 3 on it. I am not able to start Rails server. I am getting the following error.
mah@mah-laptop:~/Desktop/projects/ver$ rails s
/home/mah/.rvm/gems/ruby-1.9.2-p0/gems/railties-3.0.8/lib/rails/commands.rb:29:in `block in <top (required)>': undefined method `root' for nil:NilClass (NoMethodError)
from /home/mah/.rvm/gems/ruby-1.9.2-p0/gems/railties-3.0.8/lib/rails/commands.rb:27:in `tap'
from /home/mah/.rvm/gems/ruby-1.9.2-p0/gems/railties-3.0.8/lib/rails/commands.rb:27:in `<top (required)>'
from script/rails:6:in `require'
from script/rails:6:in `<main>'
I am using Rails 3.0.8 and rake version 0.8.7
I tried bundle exec but got same error.
Thanks for any help in advance
UPDATE
Here is what I get after bundle exec rake db:migrate --trace
mah@mah-laptop:~/Desktop/projects/ver$ bundle exec rake db:migrate --trace
rake aborted!
uninitialized constant Ver
/home/mah/.rvm/gems/ruby-1.9.2-p0/gems/aws-s3-0.6.2/lib/aws/s3/extensions.rb:206:in `const_missing_from_s3_library'
/home/mah/Desktop/projects/ver/Rakefile:7:in `<top (required)>'
/home/mah/.rvm/gems/ruby-1.9.2-p0/gems/rake-0.9.2/lib/rake/rake_module.rb:25:in `load'
/home/mah/.rvm/gems/ruby-1.9.2-p0/gems/rake-0.9.2/lib/rake/rake_module.rb:25:in `load_rakefile'
/home/mah/.rvm/gems/ruby-1.9.2-p0/gems/rake-0.9.2/lib/rake/application.rb:495:in `raw_load_rakefile'
/home/mah/.rvm/gems/ruby-1.9.2-p0/gems/rake-0.9.2/lib/rake/application.rb:78:in `block in load_rakefile'
/home/mah/.rvm/gems/ruby-1.9.2-p0/gems/rake-0.9.2/lib/rake/application.rb:129:in `standard_exception_handling'
/home/mah/.rvm/gems/ruby-1.9.2-p0/gems/rake-0.9.2/lib/rake/application.rb:77:in `load_rakefile'
/home/mah/.rvm/gems/ruby-1.9.2-p0/gems/rake-0.9.2/lib/rake/application.rb:61:in `block in run'
/home/mah/.rvm/gems/ruby-1.9.2-p0/gems/rake-0.9.2/lib/rake/application.rb:129:in `standard_exception_handling'
/home/mah/.rvm/gems/ruby-1.9.2-p0/gems/rake-0.9.2/lib/rake/application.rb:59:in `run'
/home/mah/.rvm/gems/ruby-1.9.2-p0/gems/rake-0.9.2/bin/rake:32:in `<top (required)>'
/home/mah/.rvm/gems/ruby-1.9.2-p0/bin/rake:19:in `load'
/home/mah/.rvm/gems/ruby-1.9.2-p0/bin/rake:19:in `<main>'
回答1:
This error means that Rails.application isn't initialized. I didn't actually know that, I
cheated.
So that then begs the question: how did you set up this application?
Perhaps this application doesn't contain a config/application.rb file that defines a class that inherits from Rails::Application and therefore is causing this problem. In my application here, I've got this one you could use as an example.
来源：https://stackoverflow.com/questions/6488824/not-able-to-start-rails-server