This repository has been archived by the owner on Dec 12, 2021. It is now read-only.
-
Notifications
You must be signed in to change notification settings - Fork 783
/
controller_additions.rb
317 lines (303 loc) · 12.4 KB
/
controller_additions.rb
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
module CanCan
# This module is automatically included into all controllers.
# It also makes the "can?" and "cannot?" methods available to all views.
module ControllerAdditions
module ClassMethods
# Sets up a before filter which loads and authorizes the current resource. This performs both
# load_resource and authorize_resource and accepts the same arguments. See those methods for details.
#
# class BooksController < ApplicationController
# load_and_authorize_resource
# end
#
def load_and_authorize_resource(*args)
cancan_resource_class.add_before_filter(self, :load_and_authorize_resource, *args)
end
# Sets up a before filter which loads the model resource into an instance variable.
# For example, given an ArticlesController it will load the current article into the @article
# instance variable. It does this by either calling Article.find(params[:id]) or
# Article.new(params[:article]) depending upon the action. The index action will
# automatically set @articles to Article.accessible_by(current_ability).
#
# If a conditions hash is used in the Ability, the +new+ and +create+ actions will set
# the initial attributes based on these conditions. This way these actions will satisfy
# the ability restrictions.
#
# Call this method directly on the controller class.
#
# class BooksController < ApplicationController
# load_resource
# end
#
# A resource is not loaded if the instance variable is already set. This makes it easy to override
# the behavior through a before_filter on certain actions.
#
# class BooksController < ApplicationController
# before_filter :find_book_by_permalink, :only => :show
# load_resource
#
# private
#
# def find_book_by_permalink
# @book = Book.find_by_permalink!(params[:id)
# end
# end
#
# If a name is provided which does not match the controller it assumes it is a parent resource. Child
# resources can then be loaded through it.
#
# class BooksController < ApplicationController
# load_resource :author
# load_resource :book, :through => :author
# end
#
# Here the author resource will be loaded before each action using params[:author_id]. The book resource
# will then be loaded through the @author instance variable.
#
# That first argument is optional and will default to the singular name of the controller.
# A hash of options (see below) can also be passed to this method to further customize it.
#
# See load_and_authorize_resource to automatically authorize the resource too.
#
# Options:
# [:+only+]
# Only applies before filter to given actions.
#
# [:+except+]
# Does not apply before filter to given actions.
#
# [:+through+]
# Load this resource through another one. This should match the name of the parent instance variable or method.
#
# [:+through_association+]
# The name of the association to fetch the child records through the parent resource. This is normally not needed
# because it defaults to the pluralized resource name.
#
# [:+shallow+]
# Pass +true+ to allow this resource to be loaded directly when parent is +nil+. Defaults to +false+.
#
# [:+singleton+]
# Pass +true+ if this is a singleton resource through a +has_one+ association.
#
# [:+parent+]
# True or false depending on if the resource is considered a parent resource. This defaults to +true+ if a resource
# name is given which does not match the controller.
#
# [:+class+]
# The class to use for the model (string or constant).
#
# [:+instance_name+]
# The name of the instance variable to load the resource into.
#
# [:+find_by+]
# Find using a different attribute other than id. For example.
#
# load_resource :find_by => :permalink # will use find_by_permlink!(params[:id])
#
# [:+collection+]
# Specify which actions are resource collection actions in addition to :+index+. This
# is usually not necessary because it will try to guess depending on if the id param is present.
#
# load_resource :collection => [:sort, :list]
#
# [:+new+]
# Specify which actions are new resource actions in addition to :+new+ and :+create+.
# Pass an action name into here if you would like to build a new resource instead of
# fetch one.
#
# load_resource :new => :build
#
def load_resource(*args)
cancan_resource_class.add_before_filter(self, :load_resource, *args)
end
# Sets up a before filter which authorizes the resource using the instance variable.
# For example, if you have an ArticlesController it will check the @article instance variable
# and ensure the user can perform the current action on it. Under the hood it is doing
# something like the following.
#
# authorize!(params[:action].to_sym, @article || Article)
#
# Call this method directly on the controller class.
#
# class BooksController < ApplicationController
# authorize_resource
# end
#
# If you pass in the name of a resource which does not match the controller it will assume
# it is a parent resource.
#
# class BooksController < ApplicationController
# authorize_resource :author
# authorize_resource :book
# end
#
# Here it will authorize :+show+, @+author+ on every action before authorizing the book.
#
# That first argument is optional and will default to the singular name of the controller.
# A hash of options (see below) can also be passed to this method to further customize it.
#
# See load_and_authorize_resource to automatically load the resource too.
#
# Options:
# [:+only+]
# Only applies before filter to given actions.
#
# [:+except+]
# Does not apply before filter to given actions.
#
# [:+parent+]
# True or false depending on if the resource is considered a parent resource. This defaults to +true+ if a resource
# name is given which does not match the controller.
#
# [:+class+]
# The class to use for the model (string or constant). This passed in when the instance variable is not set.
# Pass +false+ if there is no associated class for this resource and it will use a symbol of the resource name.
#
# [:+instance_name+]
# The name of the instance variable for this resource.
#
# [:+through+]
# Authorize conditions on this parent resource when instance isn't available.
#
def authorize_resource(*args)
cancan_resource_class.add_before_filter(self, :authorize_resource, *args)
end
# Add this to a controller to ensure it performs authorization through +authorized+! or +authorize_resource+ call.
# If neither of these authorization methods are called, a CanCan::AuthorizationNotPerformed exception will be raised.
# This is normally added to the ApplicationController to ensure all controller actions do authorization.
#
# class ApplicationController < ActionController::Base
# check_authorization
# end
#
# Any arguments are passed to the +after_filter+ it triggers.
#
# See skip_authorization_check to bypass this check on specific controller actions.
def check_authorization(*args)
self.after_filter(*args) do |controller|
unless controller.instance_variable_defined?(:@_authorized)
raise AuthorizationNotPerformed, "This action failed the check_authorization because it does not authorize_resource. Add skip_authorization_check to bypass this check."
end
end
end
# Call this in the class of a controller to skip the check_authorization behavior on the actions.
#
# class HomeController < ApplicationController
# skip_authorization_check :only => :index
# end
#
# Any arguments are passed to the +before_filter+ it triggers.
def skip_authorization_check(*args)
self.before_filter(*args) do |controller|
controller.instance_variable_set(:@_authorized, true)
end
end
def skip_authorization(*args)
raise ImplementationRemoved, "The CanCan skip_authorization method has been renamed to skip_authorization_check. Please update your code."
end
def cancan_resource_class
if ancestors.map(&:to_s).include? "InheritedResources::Actions"
InheritedResource
else
ControllerResource
end
end
end
def self.included(base)
base.extend ClassMethods
base.helper_method :can?, :cannot?
end
# Raises a CanCan::AccessDenied exception if the current_ability cannot
# perform the given action. This is usually called in a controller action or
# before filter to perform the authorization.
#
# def show
# @article = Article.find(params[:id])
# authorize! :read, @article
# end
#
# A :message option can be passed to specify a different message.
#
# authorize! :read, @article, :message => "Not authorized to read #{@article.name}"
#
# You can also use I18n to customize the message. Action aliases defined in Ability work here.
#
# en:
# unauthorized:
# manage:
# all: "Not authorized to %{action} %{subject}."
# user: "Not allowed to manage other user accounts."
# update:
# project: "Not allowed to update this project."
#
# You can rescue from the exception in the controller to customize how unauthorized
# access is displayed to the user.
#
# class ApplicationController < ActionController::Base
# rescue_from CanCan::AccessDenied do |exception|
# flash[:error] = exception.message
# redirect_to root_url
# end
# end
#
# See the CanCan::AccessDenied exception for more details on working with the exception.
#
# See the load_and_authorize_resource method to automatically add the authorize! behavior
# to the default RESTful actions.
def authorize!(*args)
@_authorized = true
current_ability.authorize!(*args)
end
def unauthorized!(message = nil)
raise ImplementationRemoved, "The unauthorized! method has been removed from CanCan, use authorize! instead."
end
# Creates and returns the current user's ability and caches it. If you
# want to override how the Ability is defined then this is the place.
# Just define the method in the controller to change behavior.
#
# def current_ability
# # instead of Ability.new(current_user)
# @current_ability ||= UserAbility.new(current_account)
# end
#
# Notice it is important to cache the ability object so it is not
# recreated every time.
def current_ability
@current_ability ||= ::Ability.new(current_user)
end
# Use in the controller or view to check the user's permission for a given action
# and object.
#
# can? :destroy, @project
#
# You can also pass the class instead of an instance (if you don't have one handy).
#
# <% if can? :create, Project %>
# <%= link_to "New Project", new_project_path %>
# <% end %>
#
# If it's a nested resource, you can pass the parent instance in a hash. This way it will
# check conditions which reach through that association.
#
# <% if can? :create, @category => Project %>
# <%= link_to "New Project", new_project_path %>
# <% end %>
#
# This simply calls "can?" on the current_ability. See Ability#can?.
def can?(*args)
current_ability.can?(*args)
end
# Convenience method which works the same as "can?" but returns the opposite value.
#
# cannot? :destroy, @project
#
def cannot?(*args)
current_ability.cannot?(*args)
end
end
end
if defined? ActionController
ActionController::Base.class_eval do
include CanCan::ControllerAdditions
end
end