我正在尝试使用最新版本的activerecord-postgres-hstore gem在Rails 3.2.9项目中使用Hstore,并且在使用ActiveRecord为Hstore中的值提供的store_accessor时遇到了一些麻烦。
我的模型如下所示:
class Person < ActiveRecord::Base
serialize :data, ActiveRecord::Coders::Hstore
attr_accessible :data, :name
store_accessor :data, :age, :gender
end
当我进入 rails 控制台时,我得到了:
Loading development environment (Rails 3.2.9)
1.9.3-p327 :001 > p = Person.find(3)
Person Load (9.8ms) SELECT "people".* FROM "people" WHERE "people"."id" = $1 LIMIT 1 [["id", 3]]
=> #<Person id: 3, name: "Leo", data: {"age"=>"34", "gender"=>"male"}, created_at: "2012-12-07 15:01:53", updated_at: "2012-12-07 15:27:40">
1.9.3-p327 :002 > p.age
=> nil
1.9.3-p327 :003 > p.age = "204"
=> "204"
1.9.3-p327 :004 > p.save!
(0.2ms) BEGIN
(0.6ms) UPDATE "people" SET "data" = 'age=>34,gender=>male,age=>204', "updated_at" = '2012-12-07 15:28:33.097404' WHERE "people"."id" = 3
(2.2ms) COMMIT
=> true
1.9.3-p327 :005 > p
=> #<Person id: 3, name: "Leo", data: {"age"=>"204", "gender"=>"male"}, created_at: "2012-12-07 15:01:53", updated_at: "2012-12-07 15:28:33">
1.9.3-p327 :006 > exit
% rails c 12-12-07 - 10:28:35
Loading development environment (Rails 3.2.9)
1.9.3-p327 :001 > p = Person.find(3)
Person Load (6.9ms) SELECT "people".* FROM "people" WHERE "people"."id" = $1 LIMIT 1 [["id", 3]]
=> #<Person id: 3, name: "Leo", data: {"age"=>"34", "gender"=>"male"}, created_at: "2012-12-07 15:01:53", updated_at: "2012-12-07 15:28:33">
请注意,"保存!"确实会更新此人。当我退出控制台并返回记录时,返回到原始数据集。
另外,请注意,当我尝试访问age
时,它返回 nil。
如果有人想知道这是store_accessor
方法在活动记录中的作用
商店.rb
def store_accessor(store_attribute, *keys)
Array(keys).flatten.each do |key|
define_method("#{key}=") do |value|
send("#{store_attribute}=", {}) unless send(store_attribute).is_a?(Hash)
send(store_attribute)[key] = value
send("#{store_attribute}_will_change!")
end
define_method(key) do
send("#{store_attribute}=", {}) unless send(store_attribute).is_a?(Hash)
send(store_attribute)[key]
end
end
end
这很奇怪,因为当我在控制台中执行相同的send(store_attribute)[key]
行时,它可以工作:
1.9.3-p327 :010 > p.send(:data)['age']
=> "34"
1.9.3-p327 :011 > p.send(:data)['age'] = "500"
=> "500"
1.9.3-p327 :012 > p.send("data_will_change!")
=> {"age"=>"500", "gender"=>"male"}
1.9.3-p327 :013 > p.save!
(0.2ms) BEGIN
(0.7ms) UPDATE "people" SET "data" = 'age=>500,gender=>male', "updated_at" = '2012-12-07 15:41:50.404719' WHERE "people"."id" = 3
(1.8ms) COMMIT
=> true
1.9.3-p327 :014 > p
=> #<Person id: 3, name: "Leo", data: {"age"=>"500", "gender"=>"male"}, created_at: "2012-12-07 15:01:53", updated_at: "2012-12-07 15:41:50">
1.9.3-p327 :015 > exit
% rails c 12-12-07 - 10:41:57
Loading development environment (Rails 3.2.9)
1.9.3-p327 :001 > p = Person.find(3)
Person Load (9.3ms) SELECT "people".* FROM "people" WHERE "people"."id" = $1 LIMIT 1 [["id", 3]]
=> #<Person id: 3, name: "Leo", data: {"age"=>"500", "gender"=>"male"}, created_at: "2012-12-07 15:01:53", updated_at: "2012-12-07 15:41:50">
1.9.3-p327 :002 >
知道这里会发生什么吗?
我最终一起删除了store_accessor,并使用以下代码为 hstore 键添加访问器
lib/hstore_accessor.rb
module HstoreAccessor
def self.included(base)
base.extend(ClassMethods)
end
module ClassMethods
def hstore_accessor(hstore_attribute, *keys)
Array(keys).flatten.each do |key|
define_method("#{key}=") do |value|
send("#{hstore_attribute}=", (send(hstore_attribute) || {}).merge(key.to_s => value))
send("#{hstore_attribute}_will_change!")
end
define_method(key) do
send(hstore_attribute) && send(hstore_attribute)[key.to_s]
end
end
end
end
end
ActiveRecord::Base.send(:include, HstoreAccessor)
config/initializers/active_record_extensions.rb
require "hstore_accessor"
人
class Person < ActiveRecord::Base
hstore_accessor :data, :size, :shape, :smell
end