blob: da6bc8795082e1cc04145ecc8097a4d3f6e57077 (
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
|
module ActiveRecord
# Declare an enum attribute where the values map to integers in the database, but can be queried by name. Example:
#
# class Conversation < ActiveRecord::Base
# enum status: [ :active, :archived ]
# end
#
# Conversation::STATUS # => { active: 0, archived: 1 }
#
# # conversation.update! status: 0
# conversation.active!
# conversation.active? # => true
# conversation.status # => :active
#
# # conversation.update! status: 1
# conversation.archived!
# conversation.archived? # => true
# conversation.status # => :archived
#
# # conversation.update! status: 1
# conversation.status = :archived
#
# You can set the default value from the database declaration, like:
#
# create_table :conversations do |t|
# t.column :status, :integer, default: 0
# end
#
# Good practice is to let the first declared status be the default.
#
# Finally, it's also possible to explicitly map the relation between attribute and database integer:
#
# class Conversation < ActiveRecord::Base
# enum status: { active: 0, archived: 1 }
# end
module Enum
def enum(definitions)
definitions.each do |name, values|
enum_values = {}
name = name.to_sym
# def direction=(value) self[:direction] = DIRECTION[value] end
define_method("#{name}=") { |value| self[name] = enum_values[value] }
# def direction() DIRECTION.key self[:direction] end
define_method(name) { enum_values.key self[name] }
pairs = values.respond_to?(:each_pair) ? values.each_pair : values.each_with_index
pairs.each do |value, i|
enum_values[value] = i
# scope :incoming, -> { where direction: 0 }
scope value, -> { where name => i }
# def incoming?() direction == 0 end
define_method("#{value}?") { self[name] == i }
# def incoming! update! direction: :incoming end
define_method("#{value}!") { update! name => value.to_sym }
end
end
end
end
end
|