Saving files using Paperclip without upload - ruby-on-rails

Question

I had a quick question. Is it possible to save a file without actually uploading it through a form?
For example, let's say I'm looking at attachments from emails, and I want to save them using a paperclip. How do I do this? Do I manually have to call a save_file(or something similar) somewhere?
Any help would be much appreciated!

Answer 1

I have a rake task that loads images (client logos) from a directory directly onto parperclip. You can probably adapt it to your needs.
This is my simplified Client model:
class Client < ActiveRecord::Base
LOGO_STYLES = {
:original => ['1024x768>', :jpg],
:medium => ['256x192#', :jpg],
:small => ['128x96#', :jpg]
}
has_attached_file :logo,
:styles => Client::LOGO_STYLES,
:url => "/clients/logo/:id.jpg?style=:style"
attr_protected :logo_file_name, :logo_content_type, :logo_size
Then on my rake task I do this:
# the logos are in a folder with path logos_dir
Dir.glob(File.join(logos_dir,'*')).each do |logo_path|
if File.basename(logo_path)[0]!= '.' and !File.directory? logo_path
client_code = File.basename(logo_path, '.*') #filename without extension
client = Client.find_by_code(client_code) #you could use the ids, too
raise "could not find client for client_code #{client_code}" if client.nil?
File.open(logo_path) do |f|
client.logo = f # just assign the logo attribute to a file
client.save
end #file gets closed automatically here
end
end
Regards!

Answer 2

The file saved in Paperclip doesn't have to be uploaded directly through a form.
I'm using Paperclip in a project to save files from URLs from webcrawler results. I'm not sure how you'd get email attachments (are they on the local file system of the server? Is your app an email app like GMail?) but as long as you can get a file stream (via something like open(URI.parse(crawl_result)) in my case...) you can attach that file to your model field that's marked has_attached_file.
This blog post about Easy Upload via URL with Paperclip helped me figure this out.
Since it now appears the original blog post is no longer available - here's the gist of it pulled from wayback machine:
This example shows a Photo model that has an Image attachment.
The technique we're using requires adding a *_remote_url (string) column for your attachment, which is used to store the original URL. So, in this case, we need to add a column named image_remote_url the photos table.
# db/migrate/20081210200032_add_image_remote_url_to_photos.rb
class AddImageRemoteUrlToPhotos < ActiveRecord::Migration
def self.up
add_column :photos, :image_remote_url, :string
end
def self.down
remove_column :photos, :image_remote_url
end
end
Nothing special is required for the controller...
# app/controllers/photos_controller.rb
class PhotosController < ApplicationController
def create
#photo = Photo.new(params[:photo])
if #photo.save
redirect_to photos_path
else
render :action => 'new'
end
end
end
In the form, we add a text_field called :image_url, so people can upload a file or provide a URL...
# app/views/photos/new.html.erb
<%= error_messages_for :photo %>
<% form_for :photo, :html => { :multipart => true } do |f| %>
Upload a photo: <%= f.file_field :image %><br>
...or provide a URL: <%= f.text_field :image_url %><br>
<%= f.submit 'Submit' %>
<% end %>
The meaty stuff is in the Photo model. We need to require open-uri, add an attr_accessor :image_url, and do the normal has_attached_file stuff. Then, we add a before_validation callback to download the file in the image_url attribute (if provided) and save the original URL as image_remote_url. Finally, we do a validates_presence_of :image_remote_url, which allows us to rescue from the many exceptions that can be raised when attempting to download the file.
# app/models/photo.rb
require 'open-uri'
class Photo < ActiveRecord::Base
attr_accessor :image_url
has_attached_file :image # etc...
before_validation :download_remote_image, :if => :image_url_provided?
validates_presence_of :image_remote_url, :if => :image_url_provided?, :message => 'is invalid or inaccessible'
private
def image_url_provided?
!self.image_url.blank?
end
def download_remote_image
self.image = do_download_remote_image
self.image_remote_url = image_url
end
def do_download_remote_image
io = open(URI.parse(image_url))
def io.original_filename; base_uri.path.split('/').last; end
io.original_filename.blank? ? nil : io
rescue # catch url errors with validations instead of exceptions (Errno::ENOENT, OpenURI::HTTPError, etc...)
end
end
Everything will work as normal, including the creation of thumbnails, etc. Plus, since we're doing all of the hard stuff in the model, "uploading" a file via URL works from within script/console as well:
$ script/console
Loading development environment (Rails 2.2.2)
>> Photo.new(:image_url => 'http://www.google.com/intl/en_ALL/images/logo.gif')
=> #<Photo image_file_name: "logo.gif", image_remote_url: "http://www.google.com/intl/en_ALL/images/logo.gif">