Global access to Rake DSL methods is deprecated

I am working through the Ruby on Rails 3 tutorial book and typed the following on the command line:

rake db:migrate

which produced the following warning.

WARNING: Global access to Rake DSL methods is deprecated.  Please Include
    ...  Rake::DSL into classes and modules which use the Rake DSL methods.

WARNING: DSL method DemoApp::Application#task called at /Users/imac/.rvm/gems/ruby-1.9.2-p180@rails3tutorial/gems/railties-3.0.7/lib/rails/application.rb:215:in `initialize_tasks'

I am not sure what to do about it or how to work with it. I don't know any other command for Rake.

How can I fix this problem?

Adding include Rake::DSL to the Rakefile before the applications load_tasks were called also worked for me.

So in the above user's case before the DemoApp::Application.load_tasks in the Rakefile.

I found this in Stack Overflow question Ruby on Rails and Rake problems: uninitialized constant Rake::DSL. It refers to a @DHH tweet.

Put the following in your Gemfile

gem "rake", "0.8.7"

You may see something like

rake aborted!
You have already activated Rake 0.9.1 ...

I still had a copy of Rake 0.9.1 in my directory so I deleted it.

You can "delete" Rake 0.9.1 by running the following command:

gem uninstall rake -v=0.9.1

If you have multiple versions of the gem installed, you'll be prompted to pick a version.

After 0.9.1 was cleaned out, I ran

bundle update rake

and was finally able to create my database files. I was using rake db:create, but it should work for rake db:migrate as well.

I hope it helps.

I was having the same problem on Windows with the installer. Ruby 1.9.2 and Rails 3.0.9. Here is what I did:

bundle update rake
bundle show rake

After doing that I was running rake 0.9.2.

Then I updated the Rakefile in application root folder as follows:

require File.expand_path('../config/application', __FILE__)
require 'rake'
# If you named your application something other than SampleApp, change that below
module ::SampleApp
	class Application
		include Rake::DSL
	end
end

module ::RakeFileUtils
	extend Rake::FileUtilsExt
end

SampleApp::Application.load_tasks

As noted in the comment, make sure the name of your app is correct in the two appropriate lines above.

If you are seeing this on later versions of Rails (like 3.+) you may also want to verify that your environment is clean by using RVM <http://beginrescueend.com/> and creating a specific ruby & gemset for your projects.

Use an .rvmrc file on a per-project basis, this will guarantee you aren't getting older system gems into your projects. Which has bitten me before.

This prevents having to monkey around with generated Rakefiles & such.

bundle exec rake db:migrate will solve your ruby version issues