aboutsummaryrefslogtreecommitdiffstats
path: root/actionpack/lib/abstract_controller/callbacks.rb
blob: 7004e607a179ec6ec071b40316621238892e6a86 (plain) (blame)
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
module AbstractController
  module Callbacks
    extend ActiveSupport::Concern

    # Uses ActiveSupport::Callbacks as the base functionality. For
    # more details on the whole callback system, read the documentation
    # for ActiveSupport::Callbacks.
    include ActiveSupport::Callbacks

    included do
      define_callbacks :process_action, :terminator => "response_body"
    end

    # Override AbstractController::Base's process_action to run the
    # process_action callbacks around the normal behavior.
    def process_action(*args)
      run_callbacks(:process_action, action_name) do
        super
      end
    end

    module ClassMethods
      # If :only or :except are used, convert the options into the
      # primitive form (:per_key) used by ActiveSupport::Callbacks.
      # The basic idea is that :only => :index gets converted to
      # :if => proc {|c| c.action_name == "index" }, but that the
      # proc is only evaluated once per action for the lifetime of
      # a Rails process.
      #
      # ==== Options
      # * <tt>only</tt>   - The callback should be run only for this action
      # * <tt>except</tt>  - The callback should be run for all actions except this action
      def _normalize_callback_options(options)
        if only = options[:only]
          only = Array(only).map {|o| "action_name == '#{o}'"}.join(" || ")
          options[:per_key] = {:if => only}
        end
        if except = options[:except]
          except = Array(except).map {|e| "action_name == '#{e}'"}.join(" || ")
          options[:per_key] = {:unless => except}
        end
      end

      # Skip before, after, and around filters matching any of the names
      #
      # ==== Parameters
      # * <tt>names</tt> - A list of valid names that could be used for
      #   callbacks. Note that skipping uses Ruby equality, so it's
      #   impossible to skip a callback defined using an anonymous proc
      #   using #skip_filter
      def skip_filter(*names, &blk)
        skip_before_filter(*names)
        skip_after_filter(*names)
        skip_around_filter(*names)
      end

      # Take callback names and an optional callback proc, normalize them,
      # then call the block with each callback. This allows us to abstract
      # the normalization across several methods that use it.
      #
      # ==== Parameters
      # * <tt>callbacks</tt> - An array of callbacks, with an optional
      #   options hash as the last parameter.
      # * <tt>block</tt>    - A proc that should be added to the callbacks.
      #
      # ==== Block Parameters
      # * <tt>name</tt>     - The callback to be added
      # * <tt>options</tt>  - A hash of options to be used when adding the callback
      def _insert_callbacks(callbacks, block)
        options = callbacks.last.is_a?(Hash) ? callbacks.pop : {}
        _normalize_callback_options(options)
        callbacks.push(block) if block
        callbacks.each do |callback|
          yield callback, options
        end
      end

      ##
      # :method: before_filter
      #
      # :call-seq: before_filter(names, block)
      #
      # Append a before filter. See _insert_callbacks for parameter details.

      ##
      # :method: prepend_before_filter
      #
      # :call-seq: prepend_before_filter(names, block)
      #
      # Prepend a before filter. See _insert_callbacks for parameter details.

      ##
      # :method: skip_before_filter
      #
      # :call-seq: skip_before_filter(names, block)
      #
      # Skip a before filter. See _insert_callbacks for parameter details.

      ##
      # :method: append_before_filter
      #
      # :call-seq: append_before_filter(names, block)
      #
      # Append a before filter. See _insert_callbacks for parameter details.

      ##
      # :method: after_filter
      #
      # :call-seq: after_filter(names, block)
      #
      # Append an after filter. See _insert_callbacks for parameter details.

      ##
      # :method: prepend_after_filter
      #
      # :call-seq: prepend_after_filter(names, block)
      #
      # Prepend an after filter. See _insert_callbacks for parameter details.

      ##
      # :method: skip_after_filter
      #
      # :call-seq: skip_after_filter(names, block)
      #
      # Skip an after filter. See _insert_callbacks for parameter details.

      ##
      # :method: append_after_filter
      #
      # :call-seq: append_after_filter(names, block)
      #
      # Append an after filter. See _insert_callbacks for parameter details.

      ##
      # :method: around_filter
      #
      # :call-seq: around_filter(names, block)
      #
      # Append an around filter. See _insert_callbacks for parameter details.

      ##
      # :method: prepend_around_filter
      #
      # :call-seq: prepend_around_filter(names, block)
      #
      # Prepend an around filter. See _insert_callbacks for parameter details.

      ##
      # :method: skip_around_filter
      #
      # :call-seq: skip_around_filter(names, block)
      #
      # Skip an around filter. See _insert_callbacks for parameter details.

      ##
      # :method: append_around_filter
      #
      # :call-seq: append_around_filter(names, block)
      #
      # Append an around filter. See _insert_callbacks for parameter details.

      # set up before_filter, prepend_before_filter, skip_before_filter, etc.
      # for each of before, after, and around.
      [:before, :after, :around].each do |filter|
        class_eval <<-RUBY_EVAL, __FILE__, __LINE__ + 1
          # Append a before, after or around filter. See _insert_callbacks
          # for details on the allowed parameters.
          def #{filter}_filter(*names, &blk)                                                 # def before_filter(*names, &blk)
            _insert_callbacks(names, blk) do |name, options|                                 #   _insert_callbacks(names, blk) do |name, options|
              options[:if] = (Array.wrap(options[:if]) << "!halted") if #{filter == :after}  #     options[:if] = (Array.wrap(options[:if]) << "!halted") if false
              set_callback(:process_action, :#{filter}, name, options)                       #     set_callback(:process_action, :before, name, options)
            end                                                                              #   end
          end                                                                                # end

          # Prepend a before, after or around filter. See _insert_callbacks
          # for details on the allowed parameters.
          def prepend_#{filter}_filter(*names, &blk)                                            # def prepend_before_filter(*names, &blk)
            _insert_callbacks(names, blk) do |name, options|                                    #   _insert_callbacks(names, blk) do |name, options|
              options[:if] = (Array.wrap(options[:if]) << "!halted") if #{filter == :after}     #     options[:if] = (Array.wrap(options[:if]) << "!halted") if false
              set_callback(:process_action, :#{filter}, name, options.merge(:prepend => true))  #     set_callback(:process_action, :before, name, options.merge(:prepend => true))
            end                                                                                 #   end
          end                                                                                   # end

          # Skip a before, after or around filter. See _insert_callbacks
          # for details on the allowed parameters.
          def skip_#{filter}_filter(*names, &blk)                        # def skip_before_filter(*names, &blk)
            _insert_callbacks(names, blk) do |name, options|             #   _insert_callbacks(names, blk) do |name, options|
              skip_callback(:process_action, :#{filter}, name, options)  #     skip_callback(:process_action, :before, name, options)
            end                                                          #   end
          end                                                            # end

          # *_filter is the same as append_*_filter
          alias_method :append_#{filter}_filter, :#{filter}_filter  # alias_method :append_before_filter, :before_filter
        RUBY_EVAL
      end
    end
  end
end