我有图片模型，它存储整个应用程序中的图片，在可成像列中存储图像所有者对象。我希望能够以不同的分辨率保存这些图片。
class Picture < AbstractModel
belongs_to :imageable, polymorphic: true
mount_uploader :image, ImageUploader
end
class User < AbstractModel
has_one :picture, class_name: Picture, as: :imageable, dependent: :destroy
accepts_nested_attributes_for :picture
end
class Event < AbstractModel
has_one :picture, class_name: Picture, as: :imageable, dependent: :destroy
accepts_nested_attributes_for :picture
end
在Carrierwave我做过
class ImageUploader < CarrierWave::Uploader::Base
version :xs if: :for_user? do
process resize_to_fit: [100, 100]
end
private
def for_user?(_picture)
# And here I hit the problem!
# model.is_a? User
end
end
我如何在这里获取图片所有者模型？
model模型上的 Picture变量引用，我已尝试使用pry的所有变量，但未成功。
当然我可以直接在这个片段中的用户和事件中存储图像链接，但是，在realworld代码中，我有大约15个使用图像的不同模型，我必须提供在ActiveAdmin CMS中编辑它的能力（但它是另一个故事：）
更新
当我创建新记录时，主要问题就出现了。所以，我试图添加inverse_of，但它没有帮助。
class Picture < AbstractModel
belongs_to :imageable, polymorphic: true, inverse_of: :pictures
mount_uploader :image, ImageUploader
class User < AbstractModel
has_one :picture, class_name: Picture, as: :imageable, dependent: :destroy, inverse_of: :imageable
accepts_nested_attributes_for :picture
以下是model方法
for_user?的状态
[5] pry(#<ImageUploader>)> ap model
Изображение для {
:id => nil,
:image => #<ImageUploader:0x005583dee8f938 @model=#<Picture id: nil, image: nil, imageable_id: nil, imageable_type: nil, created_at: nil, updated_at: nil>, @mounted_as=:image, @cache_id="1463023347-21567-5096", @filename="rootp_HE_pause-20160113_141810.jpg", @original_filename="rootp_HE_pause-20160113_141810.jpg", @file=#<CarrierWave::SanitizedFile:0x005583dee8cf30 @file="/home/kvokka/proj/volunteers/public/uploads/tmp/1463023347-21567-5096/rootp_HE_pause-20160113_141810.jpg", @original_filename=nil, @content_type="image/jpeg">, @versions={:mini=>#<ImageUploader::Uploader47012442238420:0x005583dee724a0 @model=#<Picture id: nil, image: nil, imageable_id: nil, imageable_type: nil, created_at: nil, updated_at: nil>, @mounted_as=:image>, :xs=>#<ImageUploader::Uploader47012435752020:0x005583dee72450 @model=#<Picture id: nil, image: nil, imageable_id: nil, imageable_type: nil, created_at: nil, updated_at: nil>, @mounted_as=:image>, :avatar=>#<ImageUploader::Uploader47012437005860:0x005583dee72428 @model=#<Picture id: nil, image: nil, imageable_id: nil, imageable_type: nil, created_at: nil, updated_at: nil>, @mounted_as=:image>}>,
:imageable_id => nil,
:imageable_type => nil,
:created_at => nil,
:updated_at => nil
UPDATE2
我用inverse_of :: picture和inverse_of :: pictures进行了争吵。语法错误。它使用inverse_of :: imageable运行，但结果是相同的。
最后一个版本的ImageUploader（我为了简洁而剪了它）是
class ImageUploader < CarrierWave::Uploader::Base
version :xs do
process resize_to_fit: [100, 100]
end
version :avatar, if: :for_user? do
process resize_to_fit: [360, 360]
end
private
def for_user?(_)
model.imageable.is_a? User
end
end
UPDATE3
我做了一些控制台移动，所以你可以看到，该模型接受嵌套属性。在has_one关系的情况下，它也可以在没有#inverse_of方法的情况下工作（这一刻对我来说很棘手）。所以，日志：
[43] pry(main)> ap v = VolunteerCenter.create(title: 'tst', address:'tst', city: City.first, phone:'123456',email: 'mm@mm.ru', description: 'ololo', link: 'http://ddd.ru', picture: (Picture.new( remote_image_url: 'https://retina.news.mail.ru/prev780x440/pic/e5/35/image25749462_adfc024a9b54b718c1a755445661b099.jpg')))
City Load (0.8ms) SELECT "cities".* FROM "cities" ORDER BY "cities"."id" ASC LIMIT 1
(0.2ms) BEGIN
SQL (0.4ms) INSERT INTO "volunteer_centers" ("title", "address", "city_id", "phone", "email", "description", "link", "created_at", "updated_at") VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9) RETURNING "id" [["title", "tst"], ["address", "tst"], ["city_id", 1], ["phone", "123456"], ["email", "mm@mm.ru"], ["description", "ololo"], ["link", "http://ddd.ru"], ["created_at", "2016-05-12 12:13:44.417945"], ["updated_at", "2016-05-12 12:13:44.417945"]]
SQL (0.3ms) INSERT INTO "pictures" ("image", "imageable_type", "imageable_id", "created_at", "updated_at") VALUES ($1, $2, $3, $4, $5) RETURNING "id" [["image", "image25749462_adfc024a9b54b718c1a755445661b099.jpg"], ["imageable_type", "VolunteerCenter"], ["imageable_id", 11], ["created_at", "2016-05-12 12:13:44.421458"], ["updated_at", "2016-05-12 12:13:44.421458"]]
(2.2ms) COMMIT
tst {
:id => 11,
:title => "tst",
:created_at => Thu, 12 May 2016 12:13:44 UTC +00:00,
:updated_at => Thu, 12 May 2016 12:13:44 UTC +00:00,
:address => "tst",
:city_id => 1,
:phone => "123456",
:email => "mm@mm.ru",
:description => "ololo",
:vk_link => nil,
:link => "http://ddd.ru"
}
=> nil
[44] pry(main)> ap v.picture
VolunteerCenter Load (0.6ms) SELECT "volunteer_centers".* FROM "volunteer_centers" WHERE "volunteer_centers"."id" = $1 LIMIT 1 [["id", 11]]
Изображение для tst {
:id => 120,
:image => #<ImageUploader:0x0055596544d928 @model=#<Picture id: 120, image: "image25749462_adfc024a9b54b718c1a755445661b099.jpg", imageable_id: 11, imageable_type: "VolunteerCenter", created_at: "2016-05-12 12:13:44", updated_at: "2016-05-12 12:13:44">, @mounted_as=:image, @cache_id=nil, @filename="image25749462_adfc024a9b54b718c1a755445661b099.jpg", @original_filename="image25749462_adfc024a9b54b718c1a755445661b099.jpg", @file=#<CarrierWave::SanitizedFile:0x00555963f0c690 @file="/home/kvokka/proj/volunteers/public/uploads/picture/image/120/image25749462_adfc024a9b54b718c1a755445661b099.jpg", @original_filename=nil, @content_type="image/jpeg">, @versions={:mini=>#<ImageUploader::Uploader46921211280280:0x00555966c55890 @model=#<Picture id: 120, image: "image25749462_adfc024a9b54b718c1a755445661b099.jpg", imageable_id: 11, imageable_type: "VolunteerCenter", created_at: "2016-05-12 12:13:44", updated_at: "2016-05-12 12:13:44">, @mounted_as=:image, @parent_cache_id="1463055224-8966-4735", @cache_id=nil, @filename="image25749462_adfc024a9b54b718c1a755445661b099.jpg", @original_filename="image25749462_adfc024a9b54b718c1a755445661b099.jpg", @file=#<CarrierWave::SanitizedFile:0x00555966e89620 @file="/home/kvokka/proj/volunteers/public/uploads/picture/image/120/mini_image25749462_adfc024a9b54b718c1a755445661b099.jpg", @original_filename=nil, @content_type="image/jpeg">, @versions={}, @storage=#<CarrierWave::Storage::File:0x00555966e8a4a8 @uploader=#<ImageUploader::Uploader46921211280280:0x00555966c55890 ...>>>, :xs=>#<ImageUploader::Uploader46921211274220:0x00555966c55868 @model=#<Picture id: 120, image: "image25749462_adfc024a9b54b718c1a755445661b099.jpg", imageable_id: 11, imageable_type: "VolunteerCenter", created_at: "2016-05-12 12:13:44", updated_at: "2016-05-12 12:13:44">, @mounted_as=:image, @parent_cache_id="1463055224-8966-4735", @cache_id=nil, @filename="image25749462_adfc024a9b54b718c1a755445661b099.jpg", @original_filename="image25749462_adfc024a9b54b718c1a755445661b099.jpg", @file=#<CarrierWave::SanitizedFile:0x005559659d60c0 @file="/home/kvokka/proj/volunteers/public/uploads/picture/image/120/xs_image25749462_adfc024a9b54b718c1a755445661b099.jpg", @original_filename=nil, @content_type="image/jpeg">, @versions={}, @storage=#<CarrierWave::Storage::File:0x005559659d7010 @uploader=#<ImageUploader::Uploader46921211274220:0x00555966c55868 ...>>>, :avatar==>#<ImageUploader::Uploader46921211257860:0x00555966c55840 @model=#<Picture id: 120, image: "image25749462_adfc024a9b54b718c1a755445661b099.jpg", imageable_id: 11, imageable_type: "VolunteerCenter", created_at: "2016-05-12 12:13:44", updated_at: "2016-05-12 12:13:44">, @mounted_as=:image, @parent_cache_id="1463055224-8966-4735", @cache_id=nil, @filename="image25749462_adfc024a9b54b718c1a755445661b099.jpg", @original_filename="image25749462_adfc024a9b54b718c1a755445661b099.jpg", @file=#<CarrierWave::SanitizedFile:0x00555963379328 @file="/home/kvokka/proj/volunteers/public/uploads/picture/image/120/avatar=_image25749462_adfc024a9b54b718c1a755445661b099.jpg", @original_filename=nil, @content_type="image/jpeg">, @versions={}, @storage=#<CarrierWave::Storage::File:0x0055596337a390 @uploader=#<ImageUploader::Uploader46921211257860:0x00555966c55840 ...>>>}, @storage=#<CarrierWave::Storage::File:0x00555965d85fb8 @uploader=#<ImageUploader:0x0055596544d928 ...>>>,
:imageable_id => 11,
:imageable_type => "VolunteerCenter",
:created_at => Thu, 12 May 2016 12:13:44 UTC +00:00,
:updated_at => Thu, 12 May 2016 12:13:44 UTC +00:00
}
UPDATE4
当我在回调方法中使用pry运行时会发生这种情况。
class ImageUploader < CarrierWave::Uploader::Base
version :avatar, if: :for_user? do
puts 'This line never run'
process resize_to_fit: [360, 360]
end
private
def for_user?(picture)
binding.pry
model.imageable.is_a? User
end
我关闭所有验证以澄清。
此回调被调用3次，并且在前2 User实例未准备就绪，并且在最后一个回调之后，回调不起作用。
[46] pry(main)> ap u = User.create(email: 'example@test.com', password: '123456', password_confirmation: '123456', picture: (Picture.create remote_image_url: 'http://onrails.club/uploads/default/29/31f7627609164af8.png'))
From: /home/kvokka/proj/volunteers/app/uploaders/image_uploader.rb @ line 68 ImageUploader#for_user?:
66: def for_user?(_)
67: binding.pry
=> 68: model.imageable.is_a? User
69: end
@cache_id "1463060913-8966-3349"
@file #<CarrierWave::SanitizedFile:0x00555963268330 @file="/hom...
@filename "31f7627609164af8.png"
@model #<Picture id: nil, image: nil, imageable_id: nil, imageab...
@mounted_as :image
@original_filename "31f7627609164af8.png"
@versions {:mini=>#<ImageUploader::Uploader46921199022860:0x0055596...
[1] pry(#<ImageUploader>)>
From: /home/kvokka/proj/volunteers/app/uploaders/image_uploader.rb @ line 68 ImageUploader#for_user?:
66: def for_user?(_)
67: binding.pry
=> 68: model.imageable.is_a? User
69: end
@cache_id "1463060913-8966-3349"
@file #<CarrierWave::SanitizedFile:0x00555963268330 @file="/hom...
@filename "31f7627609164af8.png"
@model #<Picture id: nil, image: nil, imageable_id: nil, imageab...
@mounted_as :image
@original_filename "31f7627609164af8.png"
@versions {:mini=>#<ImageUploader::Uploader46921199022860:0x0055596...
[1] pry(#<ImageUploader>)>
(0.3ms) BEGIN
SQL (0.7ms) INSERT INTO "pictures" ("image", "created_at", "updated_at") VALUES ($1, $2, $3) RETURNING "id" [["image", "31f7627609164af8.png"], ["created_at", "2016-05-12 13:48:40.071387"], ["updated_at", "2016-05-12 13:48:40.071387"]]
From: /home/kvokka/proj/volunteers/app/uploaders/image_uploader.rb @ line 68 ImageUploader#for_user?:
66: def for_user?(_)
67: binding.pry
=> 68: model.imageable.is_a? User
69: end
@cache_id nil
@file #<CarrierWave::SanitizedFile:0x005559639c6348 @file="/hom...
@filename "31f7627609164af8.png"
@model #<Picture id: 112, image: "31f7627609164af8.png", imageab...
@mounted_as :image
@original_filename "31f7627609164af8.png"
@storage #<CarrierWave::Storage::File:0x00555963b5add0 @uploader=#...
@versions {:mini=>#<ImageUploader::Uploader46921199022860:0x0055596...
[1] pry(#<ImageUploader>)>
(2.9ms) COMMIT
(0.2ms) BEGIN
User Exists (0.7ms) SELECT 1 AS one FROM "users" WHERE "users"."email" = 'example@test.com' LIMIT 1
SQL (0.4ms) INSERT INTO "users" ("email", "encrypted_password", "created_at", "updated_at") VALUES ($1, $2, $3, $4) RETURNING "id" [["email", "example@test.com"], ["encrypted_password", "$2a$11$qq8tVgzISJguKz7oVJWyVO45vW/ujSEsi/ow29w78nC9ByOdjrPYK"], ["created_at", "2016-05-12 13:48:41.761836"], ["updated_at", "2016-05-12 13:48:41.761836"]]
SQL (0.4ms) UPDATE "pictures" SET "imageable_type" = $1, "imageable_id" = $2, "updated_at" = $3 WHERE "pictures"."id" = $4 [["imageable_type", "User"], ["imageable_id", 31], ["updated_at", "2016-05-12 13:48:41.764681"], ["id", 112]]
(2.7ms) COMMIT
, {
:id => 31,
:email => "example@test.com",
:encrypted_password => "$2a$11$qq8tVgzISJguKz7oVJWyVO45vW/ujSEsi/ow29w78nC9ByOdjrPYK",
:reset_password_token => nil,
:reset_password_sent_at => nil,
:remember_created_at => nil,
:sign_in_count => 0,
:current_sign_in_at => nil,
:last_sign_in_at => nil,
:current_sign_in_ip => nil,
:last_sign_in_ip => nil,
:created_at => Thu, 12 May 2016 13:48:41 UTC +00:00,
:updated_at => Thu, 12 May 2016 13:48:41 UTC +00:00,
:name => nil,
:surname => nil,
:phone => nil,
:dob => nil,
:gender => nil,
:height => nil,
:about => nil,
:information_source_id => nil,
:institution_id => nil,
:clothes_size_id => nil,
:city_id => nil,
:volunteer_center_id => nil,
:blood_id => nil,
:vkontakte_link => nil,
:medical_contraindications => nil
}
=> nil
问题仍然存在
答案 0 :(得分：0)
我如何在这里获取图片所有者模型？
当您说“图片所有者模型”时，假设您指的是用户记录，那么您可以执行以下操作
class ImageUploader < CarrierWave::Uploader::Base
...
def for_user?(picture)
user = model.imageable
user.is_a? User
# => true
end
...
end
来自include_once：
picture参数是要上传的文件对象（这不是图片模型的实例）
model是对使用此ImageUploader的实例对象的引用，在您的情况下，它引用Picture模型的实例。请注意，这与上面的picture不同。
现在您知道model是Picture的实例，Picture belongs_to :imageable，:imageable是多态关联，实际上是User在你的情况下记录，然后你可以用上面的答案访问相关的记录。但请注意，它可能并不总是User记录，因为它是多态关联。
<强>更新
我猜model.imageable无法正常工作，因为从嵌套参数设置后，可成像记录为零。
你能试试吗
class Picture < AbstractModel
belongs_to :imageable, polymorphic: true, inverse_of: :picture # WITHOUT s
<强>更新
inverse_of看起来不适用于多态关联（docs和here）
inverse_of支持有一些限制：
- 他们不使用：通过协会。
- 他们不兼容：多态关联。
- 他们不能与：作为协会。
- 对于belongs_to关联，忽略has_many反向关联。
P.S。这可能很棘手。如果我以后有时间，我会尝试重现这个问题。