If you are finding a solution to implement file upload or file attachment, you almost landed to the right place.

Here I’m going to share with you how good paperclip is and why I think this is the best solution I found after working on web application development for over 7 years on almost every web platform.

After I’ve learn the basic of Ruby on Rails, I’m finding for a solution on file upload, even though it can be done through a simple HTML tag, it is not scalable.

How is your project if you are planning to move your web application into the world of Cloud?

With the common HTML file upload tag, you can’t scale and move your web application into cloud easily.

The paperclip created by thoughtbot, the creator of many favorite Gems.

A short features of paperclip are…

• It handling MIME type, file size, file name into your existing model
• It can automagically generates a different version of original image with different size
• You can move your web application into cloud environment immediately
• Working with generic file storage, Amazon S3, Rackspace Cloud Files or Heroku

Just the above features, I’ve been convinced to look at it over any other Gems such as attachment_fu which I believe it also good as well.

What your only requirement to use paperclip is only the ImageMagick which available on every platform, I’ve set the things up and paperclip working in 10 minutes!

Here is the quick steps you can follow to make the use of paperclip from you Rails application

• gem install paperclip

  or using the Bundler by adding this line into your Gemfile

  gem 'paperclip'

• Install ImageMagick, download it from http://www.imagemagick.org
• Make sure you have the ImageMagick directory in your environment PATH variable
• Edit your model by adding this line into it

  has_attached_file :banner

  (change ‘banner’ with your desired members name – This will tell paperclip to add file uploading into this model)

• Generate new migration and add 4 fields into the table, the code will look like this…

• class AddImagesToTable < ActiveRecord::Migration
  def self.up
  add_column : offers, :banner_file_name, :string
  add_column : offers, :banner_content_type, :string
  add_column : offers, :banner_file_size, :integer
  add_column : offers, :banner_updated_at,   :datetime
  end 
  
  def self.down
  remove_column : offers, :banner_file_name
  remove_column : offers, :banner_content_type
  remove_column : offers, :banner_file_size
  remove_column : offers, :banner_updated_at
  end
  end

• Migrate the database!

  rake db:migrate

• Modify the form tag, add multipart attribute…

  <%= form_for(@post, :html => {:multipart => true}) do |f| %>

• Place the file upload object inside the form tag

  <%= f.file_field :banner %>

• Now you can run and upload the file into the model!
• If you want to render the file, use this piece of code

  <%= image_tag @post.banner.url %>

That’s all the basic sample how to use paperclip, it is surprisingly easy for me.

If you are looking for advanced features of paperclip, visit the project page at Github and you will get everything.

Hope this help.