Usage
You can use store_attribute
method to add additional accessors with a type to an existing store on a model.
store_attribute(store_name, name, type, options)
Where:
store_name
: The name of the store.name
: The name of the accessor to the store.type
: A symbol such as:string
or:integer
, or a type object to be used for the accessor.options
: (optional) A hash of cast type options such asprecision
,limit
,scale
,default
.
Type casting occurs every time you write data through accessor or update store itself and when object is loaded from database.
Note that if you update store explicitly then value isn’t type casted.
Examples:
class MegaUser < User
store_attribute :settings, :ratio, :integer, limit: 1
store_attribute :settings, :login_at, :datetime
store_attribute :settings, :active, :boolean
store_attribute :settings, :color, :string, default: "red"
store_attribute :settings, :colors, :json, default: ["red", "blue"]
store_attribute :settings, :data, :datetime, default: -> { Time.now }
end
u = MegaUser.new(active: false, login_at: "2015-01-01 00:01", ratio: "63.4608")
u.login_at.is_a?(DateTime) # => true
u.login_at = DateTime.new(2015, 1, 1, 11, 0, 0)
u.ratio # => 63
u.active # => false
# Default value is set
u.color # => red
# Default array is set
u.colors # => ["red", "blue"]
# A dynamic default can also be provided
u.data # => Current time
# And we also have a predicate method
u.active? # => false
u.reload
# After loading record from db store contains casted data
u.settings["login_at"] == DateTime.new(2015, 1, 1, 11, 0, 0) # => true
# If you update store explicitly then the value returned
# by accessor isn't type casted
u.settings["ratio"] = "3.141592653"
u.ratio # => "3.141592653"
# On the other hand, writing through accessor set correct data within store
u.ratio = "3.141592653"
u.ratio # => 3
u.settings["ratio"] # => 3
You can also specify type using usual store_accessor
method:
class SuperUser < User
store_accessor :settings, :privileges, login_at: :datetime
end
Or through store
:
class User < ActiveRecord::Base
store :settings, accessors: [:color, :homepage, login_at: :datetime], coder: JSON
end