Rails 4 paperclip Background job - ruby-on-rails-4

Question

CURRENT LOGIC
First, I think I have read all the articles on paperclip and I'm still stucked despite all the infos learned... So I can say taht your help is really really precious.
Secondly, I do not use delayed_paperclip, nor s3_direct_upload (but jquery directUpload).
I have users profile with 4 differents pictures : logo, avatar, worka, workb
Each format (logo, avatar, worka, workb) has 3 styles (:small, :thumb, :medium)
User can update its pictures => so update action is concerned
The 4 files fields are in a form with other classic fields (name, email, ...)
Upload is managed by jQuery DirectUpload + Paperclip
When user click the file field to add an image:
jQuery DirectUpload uploads the file into a temp directory on s3
jQuery callbacks with the url(key)
The url is assigned as :temp to an hidden field generated in javascript
When form submit button is pressed:
I assign to paperclip the url of the file uploaded with direct upload, with the help of #user.logo.temp which contains the url(key)
Paperclip generates all styles
<input type="hidden" name="user[logo_attributes][temp]" value="https://bucketname.s3.amazonaws.com/temp/e4b46d01-5d69-483b.jpg">
MY PROBLEM: STYLES GENERATION BRINGS ME TO HEROKU IDLE and TIMEOUT #15 #12
.
ATTEMPTS: I tried to isolate the upload process to put it in a background job
.
I can't figure out how to block paperclip styles generation at the first upload and generate them after in a background job
before_post_process block all post process, even in background job
I didn't use .reprocess! Since paperclip 4, update is triggered and... infinite loop..., so I use .assign and .save instead
The file is correctly assigned from S3 hosted file, then processed by paperclip
I'm not sure about the file from file field, if it is uploaded or not (no trace of that in the console, but since the form is submited, the file too, even if unused.
.
NEED: STYLES BLOCKED THEN PROCESSING IN A BACKGROUND JOB
My Logo Model
class Logo < Document
S3_TEMP_URL_FORMAT = %r{\/\/bucketname\.s3\.amazonaws\.com\/(?<path>temp\/.+\/(?<filename>.+))\z}.freeze
has_attached_file :attachment,
styles: { medium: "300x300#" },
convert_options: { medium: "-quality 75 -strip" },
default_url: ":parent_type/:class/:style/missing.png",
path: "/documents/:parent_type/:id_partition/:class/:style/:basename.:extension"
validates_attachment :attachment,
content_type: { content_type: ["image/gif", "image/png", "image/jpg", "image/jpeg"] },
size: { less_than: 1.megabyte }
validates :temp,
# presence: true,
format: { with: S3_TEMP_URL_FORMAT }
before_save :set_attachment
after_save :set_remote_url
before_post_process :stop_process
def stop_process
false
end
def styles_process
self.attachment.assign(attachment)
self.save
end
def set_attachment
# puts "BEGIN -- SET ATTACHMENT"
tries ||= 5
s3_temp_url_data = S3_TEMP_URL_FORMAT.match(self.temp)
s3 = AWS::S3.new
s3_temp_head = s3.buckets[ENV['S3_BUCKET']].objects[s3_temp_url_data[:path]].head
self.attachment_file_name = s3_temp_url_data[:filename]
self.attachment_file_size = s3_temp_head.content_length
self.attachment_content_type = s3_temp_head.content_type
self.attachment_updated_at = s3_temp_head.last_modified
rescue AWS::S3::Errors::NoSuchKey => e
tries -= 1
if tries > 0
sleep(3)
retry
else
false
end
end
def set_remote_url
s3_temp_url_data = S3_TEMP_URL_FORMAT.match(self.temp)
s3 = AWS::S3.new
self.attachment = URI.parse(self.temp)
self.save
s3.buckets[ENV['S3_BUCKET']].objects.with_prefix(s3_temp_url_data[:path]).delete_all
end
end
My Controller
def update
account_update_params = devise_parameter_sanitizer.sanitize(:account_update)
#user = User.find(current_user.id)
if #user.update_attributes(account_update_params)
# Here is the styles processing
# This is where the Resque background job would go
#user.logo.styles_process
set_flash_message :notice, :updated
redirect_to after_update_path_for(#user)
else
render :edit
end
end
My Form
<%= form_for(resource, as: resource_name, url: registration_path(resource_name), method: :put, html: { class: "form-horizontal directUpload", role: "form" }) do |f| %>
<%= f.fields_for :logo do |l| %>
<%= l.file_field(:attachment, accept: 'image/gif,image/png,image/jpg,image/jpeg') %>
<% end %>
<input type="hidden" name="user[logo_attributes][temp]" value="https://bucketname.s3.amazonaws.com/temp/e4b46d01-5d69-483b.jpg">
<% end %>