Class: ActiveModel::Errors
Relationships & Source Files | |
Super Chains via Extension / Inclusion / Inheritance | |
Class Chain:
self,
Forwardable
|
|
Instance Chain:
|
|
Inherits: | Object |
Defined in: | activemodel/lib/active_model/errors.rb |
Overview
Provides error related functionalities 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, :blank, message: "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 self.human_attribute_name(attr, = {})
attr
end
def self.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 Translation
you will not need to implement the last two. Likewise, using 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. # => ["name cannot be nil"]
# etc..
Class Method Summary
-
.new(base) ⇒ Errors
constructor
Pass in the instance of the object that is using the errors object.
Instance Attribute Summary
::Enumerable
- Included
#many? | Returns |
Instance Method Summary
-
#[](attribute)
When passed a symbol or a name of a method, returns an array of errors for the method.
-
#add(attribute, type = :invalid, **options)
Adds a new error of
type
onattribute
. -
#added?(attribute, type = :invalid, options = {}) ⇒ Boolean
Returns
true
if an error matches providedattribute
andtype
, orfalse
otherwise. -
#as_json(options = nil)
Returns a
::Hash
that can be used as the JSON representation for this object. -
#attribute_names
Returns all error attribute names.
-
#clear
Clears all errors.
-
#delete(attribute, type = nil, **options)
Delete messages for
key
. -
#details
Returns a
::Hash
of attributes with an array of their error details. -
#each(&block)
Iterates through each error object.
-
#empty? ⇒ Boolean
Returns true if there are no errors.
-
#full_message(attribute, message)
Returns a full message for a given attribute.
-
#full_messages
(also: #to_a)
Returns all the full error messages in an array.
-
#full_messages_for(attribute)
Returns all the full error messages for a given attribute in an array.
-
#generate_message(attribute, type = :invalid, options = {})
Translates an error message in its default scope (
activemodel.errors.messages
). - #group_by_attribute
-
#has_key?(attribute)
Alias for #include?.
-
#import(error, override_options = {})
Imports one error.
-
#include?(attribute) ⇒ Boolean
(also: #has_key?, #key?)
Returns
true
if the error messages include an error for the given keyattribute
,false
otherwise. -
#key?(attribute)
Alias for #include?.
-
#merge!(other)
Merges the errors from
other
, eachError
wrapped asNestedError
. -
#messages
Returns a
::Hash
of attributes with an array of their error messages. -
#messages_for(attribute)
Returns all the error messages for a given attribute in an array.
-
#of_kind?(attribute, type = :invalid) ⇒ Boolean
Returns
true
if an error on the attribute with the given type is present, orfalse
otherwise. -
#size
Returns number of errors.
-
#to_a
Alias for #full_messages.
-
#to_hash(full_messages = false)
Returns a
::Hash
of attributes with their error messages. -
#where(attribute, type = nil, **options)
Search for errors matching
attribute
,type
, oroptions
.
::Enumerable
- Included
#compact_blank | Returns a new |
#exclude? | The negative of the |
#excluding | Returns a copy of the enumerable excluding the specified elements. |
#in_order_of | Returns a new |
#including | Returns a new array that includes the passed elements. |
#index_by | Convert an enumerable to a hash, using the block result as the key and the element as the value. |
#index_with | Convert an enumerable to a hash, using the element as the key and the block result as the value. |
#maximum | Calculates the maximum from the extracted elements. |
#minimum | Calculates the minimum from the extracted elements. |
#pick | Extract the given key from the first element in the enumerable. |
#pluck | Extract the given key from each element in the enumerable. |
#sole | Returns the sole item in the enumerable. |
#without | Alias for Enumerable#excluding. |
Constructor Details
.new(base) ⇒ Errors
Pass in the instance of the object that is using the errors object.
class Person
def initialize
@errors = ActiveModel::Errors.new(self)
end
end
# File 'activemodel/lib/active_model/errors.rb', line 117
def initialize(base) @base = base @errors = [] end
Instance Attribute Details
#errors (readonly) Also known as: #objects
[ GitHub ]# File 'activemodel/lib/active_model/errors.rb', line 107
attr_reader :errors
#objects (readonly)
Alias for #errors.
# File 'activemodel/lib/active_model/errors.rb', line 108
alias :objects :errors
Instance Method Details
#[](attribute)
# File 'activemodel/lib/active_model/errors.rb', line 229
def [](attribute) (attribute) end
#add(attribute, type = :invalid, **options)
Adds a new error of type
on attribute
. More than one error can be added to the same attribute
. If no type
is supplied, :invalid
is assumed.
person.errors.add(:name)
# Adds <#ActiveModel::Error attribute=name, type=invalid>
person.errors.add(:name, :not_implemented, message: "must be implemented")
# Adds <#ActiveModel::Error attribute=name, type=not_implemented,
={:=>"must be implemented"}>
person.errors.
# => {:name=>["is invalid", "must be implemented"]}
If type
is a string, it will be used as error message.
If type
is a symbol, it will be translated using the appropriate scope (see #generate_message).
person.errors.add(:name, :blank)
person.errors.
# => {:name=>["can't be blank"]}
person.errors.add(:name, :too_long, count: 25)
person.errors.
# => ["is too long (maximum is 25 characters)"]
If type
is a proc, it will be called, allowing for things like Time.now
to be used within an error.
If the :strict
option is set to true
, it will raise StrictValidationFailed
instead of adding the error. :strict
option can also be set to any other exception.
person.errors.add(:name, :invalid, strict: true)
# => ActiveModel::StrictValidationFailed: Name is invalid
person.errors.add(:name, :invalid, strict: NameIsInvalid)
# => NameIsInvalid: Name is invalid
person.errors. # => {}
attribute
should be set to :base
if the error is not directly associated with a single attribute.
person.errors.add(:base, :name_or_email_blank,
message: "either name or email must be present")
person.errors.
# => {:base=>["either name or email must be present"]}
person.errors.details
# => {:base=>[{error: :name_or_email_blank}]}
# File 'activemodel/lib/active_model/errors.rb', line 342
def add(attribute, type = :invalid, ** ) attribute, type, = normalize_arguments(attribute, type, ** ) error = Error.new(@base, attribute, type, ** ) if exception = [:strict] exception = ActiveModel::StrictValidationFailed if exception == true raise exception, error. end @errors.append(error) error end
#added?(attribute, type = :invalid, options = {}) ⇒ Boolean
Returns true
if an error matches provided attribute
and type
, or false
otherwise. type
is treated the same as for #add.
person.errors.add :name, :blank
person.errors.added? :name, :blank # => true
person.errors.added? :name, "can't be blank" # => true
If the error requires options, then it returns true
with the correct options, or false
with incorrect or missing options.
person.errors.add :name, :too_long, count: 25
person.errors.added? :name, :too_long, count: 25 # => true
person.errors.added? :name, "is too long (maximum is 25 characters)" # => true
person.errors.added? :name, :too_long, count: 24 # => false
person.errors.added? :name, :too_long # => false
person.errors.added? :name, "is too long" # => false
#as_json(options = nil)
Returns a ::Hash
that can be used as the JSON representation for this object. You can pass the :full_messages
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"]}
# File 'activemodel/lib/active_model/errors.rb', line 247
def as_json( = nil) to_hash( && [: ]) end
#attribute_names
# File 'activemodel/lib/active_model/errors.rb', line 237
def attribute_names @errors.map(&:attribute).uniq.freeze end
#clear
Clears all errors. Clearing the errors does not, however, make the model valid. The next time the validations are run (for example, via ActiveRecord::Validations#valid?), the errors collection will be filled again if any validations fail.
# File 'activemodel/lib/active_model/errors.rb', line 80
rdoc_method :method: clear
#delete(attribute, type = nil, **options)
#details
Returns a ::Hash
of attributes with an array of their error details.
# File 'activemodel/lib/active_model/errors.rb', line 276
def details hash = group_by_attribute.transform_values do |errors| errors.map(&:details) end hash.default = EMPTY_ARRAY hash.freeze hash end
#each(&block)
# File 'activemodel/lib/active_model/errors.rb', line 67
rdoc_method :method: each
#empty? ⇒ Boolean
Returns true if there are no errors.
# File 'activemodel/lib/active_model/errors.rb', line 90
rdoc_method :method: empty?
#full_message(attribute, message)
Returns a full message for a given attribute.
person.errors. (:name, 'is invalid') # => "Name is invalid"
# File 'activemodel/lib/active_model/errors.rb', line 451
def (attribute, ) Error. (attribute, , @base) end
#full_messages Also known as: #to_a
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.
# => ["Name is too short (minimum is 5 characters)", "Name can't be blank", "Email can't be blank"]
# File 'activemodel/lib/active_model/errors.rb', line 415
def @errors.map(&: ) end
#full_messages_for(attribute)
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. (:name)
# => ["Name is too short (minimum is 5 characters)", "Name can't be blank"]
# File 'activemodel/lib/active_model/errors.rb', line 430
def (attribute) where(attribute).map(&: ).freeze end
#generate_message(attribute, type = :invalid, options = {})
Translates an error message in its default scope (activemodel.errors.messages
).
Error
messages are first looked up in activemodel.errors.models.MODEL.attributes.ATTRIBUTE.MESSAGE
, if it’s not there, it’s looked up in activemodel.errors.models.MODEL.MESSAGE
and if that is not there also, it returns the translation of the default message (e.g. activemodel.errors.messages.MESSAGE
). 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 class Admin < User; end
and you wanted the translation for the :blank
error message for the title
attribute, it looks for these translations:
-
activemodel.errors.models.admin.attributes.title.blank
-
activemodel.errors.models.admin.blank
-
activemodel.errors.models.user.attributes.title.blank
-
activemodel.errors.models.user.blank
-
any default you provided through the
options
hash (in theactivemodel.errors
scope) -
activemodel.errors.messages.blank
-
errors.attributes.title.blank
-
errors.messages.blank
# File 'activemodel/lib/active_model/errors.rb', line 479
def (attribute, type = :invalid, = {}) Error. (attribute, type, @base, ) end
#group_by_attribute
# File 'activemodel/lib/active_model/errors.rb', line 289
def group_by_attribute @errors.group_by(&:attribute) end
#has_key?(attribute)
Alias for #include?.
# File 'activemodel/lib/active_model/errors.rb', line 207
alias :has_key? :include?
#import(error, override_options = {})
Imports one error. Imported errors are wrapped as a NestedError
, providing access to original error object. If attribute or type needs to be overridden, use override_options
.
Options
-
:attribute
- Override the attribute the error belongs to. -
:type
- Override type of the error.
# File 'activemodel/lib/active_model/errors.rb', line 154
def import(error, = {}) [:attribute, :type].each do |key| if .key?(key) [key] = [key].to_sym end end @errors.append(NestedError.new(@base, error, )) end
#include?(attribute) ⇒ Boolean
Also known as: #has_key?, #key?
# File 'activemodel/lib/active_model/errors.rb', line 202
def include?(attribute) @errors.any? { |error| error.match?(attribute.to_sym) } end
#key?(attribute)
Alias for #include?.
# File 'activemodel/lib/active_model/errors.rb', line 208
alias :key? :include?
#merge!(other)
Merges the errors from other
, each Error
wrapped as NestedError
.
Parameters
-
other
- TheErrors
instance.
Examples
person.errors.merge!(other)
#messages
Returns a ::Hash
of attributes with an array of their error messages.
# File 'activemodel/lib/active_model/errors.rb', line 268
def hash = to_hash hash.default = EMPTY_ARRAY hash.freeze hash end
#messages_for(attribute)
Returns all the 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. (:name)
# => ["is too short (minimum is 5 characters)", "can't be blank"]
# File 'activemodel/lib/active_model/errors.rb', line 444
def (attribute) where(attribute).map(&: ) end
#of_kind?(attribute, type = :invalid) ⇒ Boolean
Returns true
if an error on the attribute with the given type is present, or false
otherwise. type
is treated the same as for #add.
person.errors.add :age
person.errors.add :name, :too_long, count: 25
person.errors.of_kind? :age # => true
person.errors.of_kind? :name # => false
person.errors.of_kind? :name, :too_long # => true
person.errors.of_kind? :name, "is too long (maximum is 25 characters)" # => true
person.errors.of_kind? :name, :not_too_long # => false
person.errors.of_kind? :name, "is too long" # => false
#size
Returns number of errors.
# File 'activemodel/lib/active_model/errors.rb', line 104
rdoc_method :method: size
#to_a
Alias for #full_messages.
# File 'activemodel/lib/active_model/errors.rb', line 418
alias :to_a :
#to_hash(full_messages = false)
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"]}
# File 'activemodel/lib/active_model/errors.rb', line 256
def to_hash( = false) = ? : : : group_by_attribute.transform_values do |errors| errors.map(& ) end end
#where(attribute, type = nil, **options)
Search for errors matching attribute
, type
, or options
.
Only supplied params will be matched.
person.errors.where(:name) # => all name errors.
person.errors.where(:name, :too_short) # => all name errors being too short
person.errors.where(:name, :too_short, minimum: 2) # => all name errors being too short and minimum is 2
# File 'activemodel/lib/active_model/errors.rb', line 189
def where(attribute, type = nil, ** ) attribute, type, = normalize_arguments(attribute, type, ** ) @errors.select { |error| error.match?(attribute, type, ** ) } end