WritePermissionFor

I like my authorization checking in my models, not in my controllers. (Call me weird.)

Also, I don't need sophisticated roles and other magic to deal with my models. That way the write_permission_for macro was born.

Example

Simple example:

class Project < ActiveRecord::Base
  belongs_to :user
  # ..
  write_permission_for :creator => true
end

project = Project.first
creator = Project.first.user
user = User.last

project.write_permission_for?(creator)
# => true
project.write_permission_for?(user)
# => false

More advanced example:

# add_column :users, :admin, :boolean, :default => false
class User < ActiveRecord::Base
  def role?(role)
    admin?
  end
end

class Project < ActiveRecord::Base
  belongs_to :user
  # ..
  write_permission_for :admin, :creator => true
end

project = Project.first
creator = Project.first.user
admin = User.find_by_admin(true)
user = User.last

project.write_permission_for?(admin)
# => true
project.write_permission_for?(creator)
# => true
project.write_permission_for?(user)
# => false

Even more advanced example:

class Release < ActiveRecord::Base
  belongs_to :project
  # ..
  write_permission_for :admin do |record, user|
    record.project.user == user
  end
end

class Project < ActiveRecord::Base
  belongs_to :user
end

class User < ActiveRecord::Base
end

release = Release.first
project_creator = release.project.user

release.write_permission_for?(project_creator)
# => true

Running the specs

You need to have the rspec, rr, and machinist gems installed (all of which you should be using anyway).

[sudo] gem install rspec rr
[sudo] gem install notahat-machinist --source http://gems.github.com

After that (and presuming SQLite is available on your system) running the specs should be a matter of:

rake

Sample output:

write_permission_for :creator => true
- is writeable for creator
- is not writeable for user
- is not writeable for admin

write_permission_for :admin
- is not writeable for user
- is not writeable for creator
- is writeable for admin

write_permission_for :admin, :creator => true
- is not writeable for user
- is writeable for creator
- is writeable for admin

write_permission_for (:admin) { |record, user| user == project.user }
- is writeable for the project creator
- is not writeable for user
- is not writeable for creator
- is writeable for admin

Copyright (c) 2009 Patrick Lenz, released under the MIT license