Cannot upload image by carrierwave - ruby-on-rails

Question

I am using carrierwave to upload my image but failed. Please help me.
Versions used:
rails (4.0.1)
carrierwave (0.10.0)
carrierwave-mongoid (0.7.1)
carrierwave_backgrounder (0.4.1)
My uploader:
#<EventImageUploader:0x007fc6a948ede8
#model=#<Event::EventImage
_id: 5876f63b6c616cea34630000,
c_at(created_at): 2017-01-12 03:21:31 UTC,
image: nil,
image_tmp: "1484191291-59956-9524/2016-12-10_23-45.jpg">,
#mounted_as=:image>
My image is nil, but the image under image_tmp exists. My sidekiq is running fine too.
Here is my worker:
class ImageWorker < ::CarrierWave::Workers::StoreAsset
def perform(*args)
super(*args)
record = ::CarrierWave::Workers::Base.perform(*args)
if record
p "success"
else
raise "record #{args} not found, failed"
end
end
end
How to make the upload works? Thank you.

Answer 1

After viewing the source of CarrierWave::Workers::StoreAsset#perform,
the reason why the image cannot be uploaded is because of embedded documents.
The line from source record = resource.find id will return nil because resource is an embedded class and you cannot find id by an embedded class.
To solve the problem, see here. My code should work if I add the following:
class Event
include Mongoid::Document
embeds_many :images
end
class EventImage
include Mongoid::Document
embedded_in :Event
mount_uploader :image, ImageUploader
process_in_background :image
def self.find(id)
bson_id = Moped::BSON::ObjectId.from_string(id) # needed for Mongoid 3
root = Event.where('images._id' => bson_id).first
root.images.find(id)
end
end
If you get the error uninitialized constant Moped::BSON, make sure to require it in the first place.