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.