jQuery-File-Upload Plugin integration into Rails

I think what instruction #4 is telling you is to simply copy the various javascript files into your custom server environment, in this case, Ruby on Rails.

It's best to use the assets pipeline to serve up Javascript in RoR.

1) download and extract the archive to your development environment, you want to extract the folder JQuery-File-Upload to app/assets/javascripts directory.

when you are done you should have:

/whatever/app/assets/javascripts/JQuery-File-Upload/stuff

So now, you have to tell rails WHEN that javascript needs to be loaded.

To keep things easy we are going to assume that that javascript is needed on EVERY page!

If your current app is fairly 'default', the javascript manifest file:

app/assets/javscripts/application.js 

controls the javascript that will be included on every page

add this line to that file:

//= require_tree .

or

//= require_tree JQuery-File-Upload

If there is only ONE directory in app/assets/javascripts, both of the above are the same.

Hi its very easy to use blueimp file upload in rails. Simply you can install gems available for blueimp file upload.Famous are Carrierwave gem & Dragonfly gem. If you have one of this gems , you can use following steps to work on blueimp

Prerequisites

have jQuery setup in your app

copy jQuery File Upload files in the proper directories of your Rails app

Models For use with the Carrierwave gem

We'll use basic Carrierwave uploader:

class AvatarUploader < CarrierWave::Uploader::Base
  storage :file
  def store_dir
    "uploads/#{model.class.to_s.underscore}/#{mounted_as}/#{model.id}"
  end
end

Let's set up a Picture model

class Picture < ActiveRecord::Base
  include Rails.application.routes.url_helpers
  mount_uploader :avatar, AvatarUploader

  #one convenient method to pass jq_upload the necessary information
  def to_jq_upload
    {
      "name" => read_attribute(:avatar),
      "size" => avatar.size,
      "url" => avatar.url,
      "thumbnail_url" => avatar.thumb.url,
      "delete_url" => picture_path(:id => id),
      "delete_type" => "DELETE" 
    }
  end
end

For use with the Dragonfly gem

set up a Picture model (make sure you have both avatar_uid and avatar_name columns in your database)

class Picture < ActiveRecord::Base
  include Rails.application.routes.url_helpers
  image_accessor :avatar

  #one convenient method to pass jq_upload the necessary information
  def to_jq_upload
    {
      "name" => read_attribute(:avatar_name),
      "size" => avatar.size,
      "url" => avatar.url,
      "thumbnail_url" => avatar.thumb('80x80#').url,
      "delete_url" => picture_path(:id => id),
      "delete_type" => "DELETE" 
    }
  end
end

Controller

First one controller to handle the downloads: (html response is for browsers using iframe sollution)

class PicturesController < ApplicationController

  def index
    @pictures = Picture.all
    render :json => @pictures.collect { |p| p.to_jq_upload }.to_json
  end

  def create
    @picture = Picture.new(params[:picture])
    if @picture.save
      respond_to do |format|
        format.html {  
          render :json => [@picture.to_jq_upload].to_json, 
          :content_type => 'text/html',
          :layout => false
        }
        format.json {  
          render :json => [@picture.to_jq_upload].to_json           
        }
      end
    else 
      render :json => [{:error => "custom_failure"}], :status => 304
    end
  end

  def destroy
    @picture = Picture.find(params[:id])
    @picture.destroy
    render :json => true
  end
end

And it's routes:

resources :pictures, :only => [:index, :create, :destroy]

Let's play

In whatever view file you want, copy paste this code and enjoy.

<h2><%= t('photos.title') %></h2>
<%= form_for Picture.new, :html => { :multipart => true, :id => "fileupload"  } do |f| %>
        <!-- The fileupload-buttonbar contains buttons to add/delete files and start/cancel the upload -->
        <div class="row fileupload-buttonbar">
            <div class="span7">
                <!-- The fileinput-button span is used to style the file input field as button -->
                <span class="btn btn-success fileinput-button">
                    <i class="icon-plus icon-white"></i>
                    <span>Add files...</span>
                    <%= f.file_field :avatar %>
                </span>
                <button type="submit" class="btn btn-primary start">
                    <i class="icon-upload icon-white"></i>
                    <span>Start upload</span>
                </button>
                <button type="reset" class="btn btn-warning cancel">
                    <i class="icon-ban-circle icon-white"></i>
                    <span>Cancel upload</span>
                </button>
                <button type="button" class="btn btn-danger delete">
                    <i class="icon-trash icon-white"></i>
                    <span>Delete</span>
                </button>
                <input type="checkbox" class="toggle">
            </div>
            <div class="span5">
                <!-- The global progress bar -->
                <div class="progress progress-success progress-striped active fade">
                    <div class="bar" style="width:0%;"></div>
                </div>
            </div>
        </div>
        <!-- The loading indicator is shown during image processing -->
        <div class="fileupload-loading"></div>
        <br>
        <!-- The table listing the files available for upload/download -->
        <table class="table table-striped"><tbody class="files" data-toggle="modal-gallery" data-target="#modal-gallery"></tbody>
        </table>
    <% end %>
<script>
  var fileUploadErrors = {
    maxFileSize: 'File is too big',
    minFileSize: 'File is too small',
    acceptFileTypes: 'Filetype not allowed',
    maxNumberOfFiles: 'Max number of files exceeded',
    uploadedBytes: 'Uploaded bytes exceed file size',
    emptyResult: 'Empty file upload result'
  };
</script>

<!-- The template to display files available for upload -->
<script id="template-upload" type="text/x-tmpl">
{% for (var i=0, file; file=o.files[i]; i++) { %}
    <tr class="template-upload fade">
        <td class="preview"><span class="fade"></span></td>
        <td class="name"><span>{%=file.name%}</span></td>
        <td class="size"><span>{%=o.formatFileSize(file.size)%}</span></td>
        {% if (file.error) { %}
            <td class="error" colspan="2"><span class="label label-important">{%=locale.fileupload.error%}</span> {%=locale.fileupload.errors[file.error] || file.error%}</td>
        {% } else if (o.files.valid && !i) { %}
            <td>
                <div class="progress progress-success progress-striped active"><div class="bar" style="width:0%;"></div></div>
            </td>
            <td class="start">{% if (!o.options.autoUpload) { %}
                <button class="btn btn-primary">
                    <i class="icon-upload icon-white"></i>
                    <span>{%=locale.fileupload.start%}</span>
                </button>
            {% } %}</td>
        {% } else { %}
            <td colspan="2"></td>
        {% } %}
        <td class="cancel">{% if (!i) { %}
            <button class="btn btn-warning">
                <i class="icon-ban-circle icon-white"></i>
                <span>{%=locale.fileupload.cancel%}</span>
            </button>
        {% } %}</td>
    </tr>
{% } %}
</script>
<!-- The template to display files available for download -->
<script id="template-download" type="text/x-tmpl">
{% for (var i=0, file; file=o.files[i]; i++) { %}
    <tr class="template-download fade">
        {% if (file.error) { %}
            <td></td>
            <td class="name"><span>{%=file.name%}</span></td>
            <td class="size"><span>{%=o.formatFileSize(file.size)%}</span></td>
            <td class="error" colspan="2"><span class="label label-important">{%=locale.fileupload.error%}</span> {%=locale.fileupload.errors[file.error] || file.error%}</td>
        {% } else { %}
            <td class="preview">{% if (file.thumbnail_url) { %}
                <a href="{%=file.url%}" title="{%=file.name%}" rel="gallery" download="{%=file.name%}"><img src="{%=file.thumbnail_url%}"></a>
            {% } %}</td>
            <td class="name">
                <a href="{%=file.url%}" title="{%=file.name%}" rel="{%=file.thumbnail_url&&'gallery'%}" download="{%=file.name%}">{%=file.name%}</a>
            </td>
            <td class="size"><span>{%=o.formatFileSize(file.size)%}</span></td>
            <td colspan="2"></td>
        {% } %}
        <td class="delete">
            <button class="btn btn-danger" data-type="{%=file.delete_type%}" data-url="{%=file.delete_url%}">
                <i class="icon-trash icon-white"></i>
                <span>{%=locale.fileupload.destroy%}</span>
            </button>
            <input type="checkbox" name="delete" value="1">
        </td>
    </tr>
{% } %}
</script>



<!-- The jQuery UI widget factory, can be omitted if jQuery UI is already included -->
<%= javascript_include_tag 'jquery.ui.widget.js' %>
<!-- The Templates and Load Image plugins are included for the FileUpload user interface -->
<script src="https://blueimp.github.com/JavaScript-Templates/tmpl.min.js"></script>
<script src="https://blueimp.github.com/JavaScript-Load-Image/load-image.all.min.js"></script>
<!-- The Iframe Transport is required for browsers without support for XHR file uploads -->
<%= javascript_include_tag 'jquery.iframe-transport.js' %>
<%= javascript_include_tag 'jquery.fileupload.js' %>
<%= javascript_include_tag 'jquery.fileupload-ui.js' %>
<!-- add include_tag js files to config.assets.precompile in ...environments/production.rb if you have it in vendor/ assets -->

<script type="text/javascript" charset="utf-8">
    $(function () {
        // Initialize the jQuery File Upload widget:
        $('#fileupload').fileupload();
        // 
        // Load existing files:
        $.getJSON($('#fileupload').prop('action'), function (files) {
          var fu = $('#fileupload').data('blueimp-fileupload'), 
            template;
          fu._adjustMaxNumberOfFiles(-files.length);
          template = fu._renderDownload(files)
            .appendTo($('#fileupload .files'));
          // Force reflow:
          fu._reflow = fu._transition && template.length &&
            template[0].offsetWidth;
          template.addClass('in');
          $('#loading').remove();
        });

    });
</script>