Paperclip helps you implementing file attachment with ActiveRecord with Rails. Follow the example below and see how it works.
1. Install ImageMagick (ImageMagick – Manipulate Image File by Shell Commands)
- apt-get install imagemagick
2. Create a Image Model with the required Paperclip fields
- rails generate model Image image_file_name:string image_content_type:string image_file_size:integer image_updated_at:datetime
2. Edit the app/models/image.rb and specify has_attached_file attribute
class Image < ActiveRecord::Base
has_attached_file :image,
:styles => { :medium => "300x300>",
:thumb => "100x100>" }
end
The :medium and :thumb are the display styles which is shown the image in views.
3. Create the Images controller
- rails generate controller Images
4. Edit the app/controllers/images_controller.rb as follow
class ImagesController < ApplicationController
def index
@images = Image.all
end
def show
@image = Image.find(params[:id])
end
def new
@image = Image.new
end
def create
@image = Image.new(params[:image])
if @image.save
redirect_to @image
else
redirect_to images_path
end
end
def edit
@image = Image.find(params[:id])
end
def update
@image = Image.find(params[:id])
if @image.update_attributes(params[:image])
redirect_to @image
end
end
end
5. Create the following views
app/views/images/index.html.erb
<% @images.each do |x| %> <p><%= image_tag x.image.url(:thumb) %></p> <% end %>
app/views/images/new.html.erb, app/views/images/edit.html.erb
<%= form_for(@image, :html => { :multipart => true }) do |f| %>
<div class="field">
<%= f.file_field :image %>
</div>
<div class="actions">
<%= f.submit "Create" %>
</div>
<% end %>
app/views/images/show.html.erb
<%= image_tag @image.image.url %> <%= image_tag @image.image.url(:medium) %> <%= image_tag @image.image.url(:thumb) %> <%= debug @image %>
6. Add the route mapping in config/routes
... resources :images ...
7. Specify the path of the ImageMagick convert command in config/environments/development.rb. You can check the path by which convert.
... # ImageMagick path for Paperclip Paperclip.options[:command_path] = "/usr/bin/" ...
8. Start your Rails application and try to upload the image @ http://<server>:3000/images/new
9. You can access the image by http://<server>:3000/images/<id> and edit it by http://<server>:3000/images/<id>/edit.
10. See all images @ http://<server>:3000/images
11. The uploaded images are stored @ public/system/:attachment/:id/:style/:filename. In the above example, the :medium style of image with :id => 1 would be located @ public/system/images/1/medium
Done =)
Reference:
