aboutsummaryrefslogtreecommitdiffstats
path: root/activemodel/lib/active_model/errors.rb
blob: 1b467273510b45314bff2f05449248b50605041a (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
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
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
# -*- coding: utf-8 -*-

require 'active_support/core_ext/array/conversions'
require 'active_support/core_ext/string/inflections'

module ActiveModel
  # == Active \Model \Errors
  #
  # Provides a modified +Hash+ that you can include in your object
  # for handling error messages and interacting with Action View helpers.
  #
  # A minimal implementation could be:
  #
  #   class Person
  #     # Required dependency for ActiveModel::Errors
  #     extend ActiveModel::Naming
  #
  #     def initialize
  #       @errors = ActiveModel::Errors.new(self)
  #     end
  #
  #     attr_accessor :name
  #     attr_reader   :errors
  #
  #     def validate!
  #       errors.add(:name, "cannot be nil") if name.nil?
  #     end
  #
  #     # The following methods are needed to be minimally implemented
  #
  #     def read_attribute_for_validation(attr)
  #       send(attr)
  #     end
  #
  #     def Person.human_attribute_name(attr, options = {})
  #       attr
  #     end
  #
  #     def Person.lookup_ancestors
  #       [self]
  #     end
  #   end
  #
  # The last three methods are required in your object for Errors to be
  # able to generate error messages correctly and also handle multiple
  # languages. Of course, if you extend your object with ActiveModel::Translation
  # you will not need to implement the last two. Likewise, using
  # ActiveModel::Validations will handle the validation related methods
  # for you.
  #
  # The above allows you to do:
  #
  #   person = Person.new
  #   person.validate!            # => ["cannot be nil"]
  #   person.errors.full_messages # => ["name cannot be nil"]
  #   # etc..
  class Errors
    include Enumerable

    CALLBACKS_OPTIONS = [:if, :unless, :on, :allow_nil, :allow_blank, :strict]

    attr_reader :messages

    # Pass in the instance of the object that is using the errors object.
    #
    #   class Person
    #     def initialize
    #       @errors = ActiveModel::Errors.new(self)
    #     end
    #   end
    def initialize(base)
      @base     = base
      @messages = {}
    end

    def initialize_dup(other) # :nodoc:
      @messages = other.messages.dup
      super
    end

    # Clear the error messages.
    #
    #   person.errors.full_messages # => ["name cannot be nil"]
    #   person.errors.clear
    #   person.errors.full_messages # => []
    def clear
      messages.clear
    end

    # Returns +true+ if the error messages include an error for the given key
    # +attribute+, +false+ otherwise.
    #
    #   person.errors.messages        # => {:name=>["cannot be nil"]}
    #   person.errors.include?(:name) # => true
    #   person.errors.include?(:age)  # => false
    def include?(attribute)
      messages[attribute].present?
    end
    # aliases include?
    alias :has_key? :include?

    # Get messages for +key+.
    #
    #   person.errors.messages   # => {:name=>["cannot be nil"]}
    #   person.errors.get(:name) # => ["cannot be nil"]
    #   person.errors.get(:age)  # => nil
    def get(key)
      messages[key]
    end

    # Set messages for +key+ to +value+.
    #
    #   person.errors.get(:name) # => ["cannot be nil"]
    #   person.errors.set(:name, ["can't be nil"])
    #   person.errors.get(:name) # => ["can't be nil"]
    def set(key, value)
      messages[key] = value
    end

    # Delete messages for +key+. Returns the deleted messages.
    #
    #   person.errors.get(:name)    # => ["cannot be nil"]
    #   person.errors.delete(:name) # => ["cannot be nil"]
    #   person.errors.get(:name)    # => nil
    def delete(key)
      messages.delete(key)
    end

    # When passed a symbol or a name of a method, returns an array of errors
    # for the method.
    #
    #   person.errors[:name]  # => ["cannot be nil"]
    #   person.errors['name'] # => ["cannot be nil"]
    def [](attribute)
      get(attribute.to_sym) || set(attribute.to_sym, [])
    end

    # Adds to the supplied attribute the supplied error message.
    #
    #   person.errors[:name] = "must be set"
    #   person.errors[:name] # => ['must be set']
    def []=(attribute, error)
      self[attribute] << error
    end

    # Iterates through each error key, value pair in the error messages hash.
    # Yields the attribute and the error for that attribute. If the attribute
    # has more than one error message, yields once for each error message.
    #
    #   person.errors.add(:name, "can't be blank")
    #   person.errors.each do |attribute, error|
    #     # Will yield :name and "can't be blank"
    #   end
    #
    #   person.errors.add(:name, "must be specified")
    #   person.errors.each do |attribute, error|
    #     # Will yield :name and "can't be blank"
    #     # then yield :name and "must be specified"
    #   end
    def each
      messages.each_key do |attribute|
        self[attribute].each { |error| yield attribute, error }
      end
    end

    # Returns the number of error messages.
    #
    #   person.errors.add(:name, "can't be blank")
    #   person.errors.size # => 1
    #   person.errors.add(:name, "must be specified")
    #   person.errors.size # => 2
    def size
      values.flatten.size
    end

    # Returns all message values.
    #
    #   person.errors.messages # => {:name=>["cannot be nil", "must be specified"]}
    #   person.errors.values   # => [["cannot be nil", "must be specified"]]
    def values
      messages.values
    end

    # Returns all message keys.
    #
    #   person.errors.messages # => {:name=>["cannot be nil", "must be specified"]}
    #   person.errors.keys     # => [:name]
    def keys
      messages.keys
    end

    # Returns an array of error messages, with the attribute name included.
    #
    #   person.errors.add(:name, "can't be blank")
    #   person.errors.add(:name, "must be specified")
    #   person.errors.to_a # => ["name can't be blank", "name must be specified"]
    def to_a
      full_messages
    end

    # Returns the number of error messages.
    #
    #   person.errors.add(:name, "can't be blank")
    #   person.errors.count # => 1
    #   person.errors.add(:name, "must be specified")
    #   person.errors.count # => 2
    def count
      to_a.size
    end

    # Returns +true+ if no errors are found, +false+ otherwise.
    # If the error message is a string it can be empty.
    #
    #   person.errors.full_messages # => ["name cannot be nil"]
    #   person.errors.empty?        # => false
    def empty?
      all? { |k, v| v && v.empty? && !v.is_a?(String) }
    end
    # aliases empty?
    alias_method :blank?, :empty?

    # Returns an xml formatted representation of the Errors hash.
    #
    #   person.errors.add(:name, "can't be blank")
    #   person.errors.add(:name, "must be specified")
    #   person.errors.to_xml
    #   # =>
    #   #  <?xml version=\"1.0\" encoding=\"UTF-8\"?>
    #   #  <errors>
    #   #    <error>name can't be blank</error>
    #   #    <error>name must be specified</error>
    #   #  </errors>
    def to_xml(options={})
      to_a.to_xml({ root: "errors", skip_types: true }.merge!(options))
    end

    # Returns a Hash that can be used as the JSON representation for this
    # object. You can pass the <tt>:full_messages</tt> option. This determines
    # if the json object should contain full messages or not (false by default).
    #
    #   person.errors.as_json                      # => {:name=>["cannot be nil"]}
    #   person.errors.as_json(full_messages: true) # => {:name=>["name cannot be nil"]}
    def as_json(options=nil)
      to_hash(options && options[:full_messages])
    end

    # Returns a Hash of attributes with their error messages. If +full_messages+
    # is +true+, it will contain full messages (see +full_message+).
    #
    #   person.errors.to_hash       # => {:name=>["cannot be nil"]}
    #   person.errors.to_hash(true) # => {:name=>["name cannot be nil"]}
    def to_hash(full_messages = false)
      if full_messages
        self.messages.each_with_object({}) do |(attribute, array), messages|
          messages[attribute] = array.map { |message| full_message(attribute, message) }
        end
      else
        self.messages.dup
      end
    end

    # Adds +message+ to the error messages on +attribute+. More than one error
    # can be added to the same +attribute+. If no +message+ is supplied,
    # <tt>:invalid</tt> is assumed.
    #
    #   person.errors.add(:name)
    #   # => ["is invalid"]
    #   person.errors.add(:name, 'must be implemented')
    #   # => ["is invalid", "must be implemented"]
    #
    #   person.errors.messages
    #   # => {:name=>["must be implemented", "is invalid"]}
    #
    # If +message+ is a symbol, it will be translated using the appropriate
    # scope (see +generate_message+).
    #
    # If +message+ is a proc, it will be called, allowing for things like
    # <tt>Time.now</tt> to be used within an error.
    #
    # If the <tt>:strict</tt> option is set to +true+, it will raise
    # ActiveModel::StrictValidationFailed instead of adding the error.
    # <tt>:strict</tt> option can also be set to any other exception.
    #
    #   person.errors.add(:name, nil, strict: true)
    #   # => ActiveModel::StrictValidationFailed: name is invalid
    #   person.errors.add(:name, nil, strict: NameIsInvalid)
    #   # => NameIsInvalid: name is invalid
    #
    #   person.errors.messages # => {}
    #
    # +attribute+ should be set to <tt>:base</tt> if the error is not
    # directly associated with a single attribute.
    #
    #   person.errors.add(:base, "either name or email must be present")
    #   person.errors.messages
    #   # => {:base=>["either name or email must be present"]}
    def add(attribute, message = :invalid, options = {})
      message = normalize_message(attribute, message, options)
      if exception = options[:strict]
        exception = ActiveModel::StrictValidationFailed if exception == true
        raise exception, full_message(attribute, message)
      end

      self[attribute] << message
    end

    # Will add an error message to each of the attributes in +attributes+
    # that is empty.
    #
    #   person.errors.add_on_empty(:name)
    #   person.errors.messages
    #   # => {:name=>["can't be empty"]}
    def add_on_empty(attributes, options = {})
      Array(attributes).each do |attribute|
        value = @base.send(:read_attribute_for_validation, attribute)
        is_empty = value.respond_to?(:empty?) ? value.empty? : false
        add(attribute, :empty, options) if value.nil? || is_empty
      end
    end

    # Will add an error message to each of the attributes in +attributes+ that
    # is blank (using Object#blank?).
    #
    #   person.errors.add_on_blank(:name)
    #   person.errors.messages
    #   # => {:name=>["can't be blank"]}
    def add_on_blank(attributes, options = {})
      Array(attributes).each do |attribute|
        value = @base.send(:read_attribute_for_validation, attribute)
        add(attribute, :blank, options) if value.blank?
      end
    end

    # Returns +true+ if an error on the attribute with the given message is
    # present, +false+ otherwise. +message+ is treated the same as for +add+.
    #
    #   person.errors.add :name, :blank
    #   person.errors.added? :name, :blank # => true
    def added?(attribute, message = :invalid, options = {})
      message = normalize_message(attribute, message, options)
      self[attribute].include? message
    end

    # Returns all the full error messages in an array.
    #
    #   class Person
    #     validates_presence_of :name, :address, :email
    #     validates_length_of :name, in: 5..30
    #   end
    #
    #   person = Person.create(address: '123 First St.')
    #   person.errors.full_messages
    #   # => ["Name is too short (minimum is 5 characters)", "Name can't be blank", "Email can't be blank"]
    def full_messages
      map { |attribute, message| full_message(attribute, message) }
    end

    # Returns all the full error messages for a given attribute in an array.
    #
    #   class Person
    #     validates_presence_of :name, :email
    #     validates_length_of :name, in: 5..30
    #   end
    #
    #   person = Person.create()
    #   person.errors.full_messages_for(:name)
    #   # => ["Name is too short (minimum is 5 characters)", "Name can't be blank"]
    def full_messages_for(attribute)
      (get(attribute) || []).map { |message| full_message(attribute, message) }
    end

    # Returns a full message for a given attribute.
    #
    #   person.errors.full_message(:name, 'is invalid') # => "Name is invalid"
    def full_message(attribute, message)
      return message if attribute == :base
      attr_name = attribute.to_s.tr('.', '_').humanize
      attr_name = @base.class.human_attribute_name(attribute, default: attr_name)
      I18n.t(:"errors.format", {
        default:  "%{attribute} %{message}",
        attribute: attr_name,
        message:   message
      })
    end

    # Translates an error message in its default scope
    # (<tt>activemodel.errors.messages</tt>).
    #
    # Error messages are first looked up in <tt>models.MODEL.attributes.ATTRIBUTE.MESSAGE</tt>,
    # if it's not there, it's looked up in <tt>models.MODEL.MESSAGE</tt> and if
    # that is not there also, it returns the translation of the default message
    # (e.g. <tt>activemodel.errors.messages.MESSAGE</tt>). The translated model
    # name, translated attribute name and the value are available for
    # interpolation.
    #
    # When using inheritance in your models, it will check all the inherited
    # models too, but only if the model itself hasn't been found. Say you have
    # <tt>class Admin < User; end</tt> and you wanted the translation for
    # the <tt>:blank</tt> error message for the <tt>title</tt> attribute,
    # it looks for these translations:
    #
    # * <tt>activemodel.errors.models.admin.attributes.title.blank</tt>
    # * <tt>activemodel.errors.models.admin.blank</tt>
    # * <tt>activemodel.errors.models.user.attributes.title.blank</tt>
    # * <tt>activemodel.errors.models.user.blank</tt>
    # * any default you provided through the +options+ hash (in the <tt>activemodel.errors</tt> scope)
    # * <tt>activemodel.errors.messages.blank</tt>
    # * <tt>errors.attributes.title.blank</tt>
    # * <tt>errors.messages.blank</tt>
    def generate_message(attribute, type = :invalid, options = {})
      type = options.delete(:message) if options[:message].is_a?(Symbol)

      if @base.class.respond_to?(:i18n_scope)
        defaults = @base.class.lookup_ancestors.map do |klass|
          [ :"#{@base.class.i18n_scope}.errors.models.#{klass.model_name.i18n_key}.attributes.#{attribute}.#{type}",
            :"#{@base.class.i18n_scope}.errors.models.#{klass.model_name.i18n_key}.#{type}" ]
        end
      else
        defaults = []
      end

      defaults << options.delete(:message)
      defaults << :"#{@base.class.i18n_scope}.errors.messages.#{type}" if @base.class.respond_to?(:i18n_scope)
      defaults << :"errors.attributes.#{attribute}.#{type}"
      defaults << :"errors.messages.#{type}"

      defaults.compact!
      defaults.flatten!

      key = defaults.shift
      value = (attribute != :base ? @base.send(:read_attribute_for_validation, attribute) : nil)

      options = {
        default: defaults,
        model: @base.model_name.human,
        attribute: @base.class.human_attribute_name(attribute),
        value: value
      }.merge!(options)

      I18n.translate(key, options)
    end

  private
    def normalize_message(attribute, message, options)
      case message
      when Symbol
        generate_message(attribute, message, options.except(*CALLBACKS_OPTIONS))
      when Proc
        message.call
      else
        message
      end
    end
  end

  # Raised when a validation cannot be corrected by end users and are considered
  # exceptional.
  #
  #   class Person
  #     include ActiveModel::Validations
  #
  #     attr_accessor :name
  #
  #     validates_presence_of :name, strict: true
  #   end
  #
  #   person = Person.new
  #   person.name = nil
  #   person.valid?
  #   # => ActiveModel::StrictValidationFailed: Name can't be blank
  class StrictValidationFailed < StandardError
  end
end