File Upload

Using acts_as_attachment; see also attachment_fu, file_column

  1. Install acts_as_attachment

    2. script/plugin source http://svn.techno-weenie.net/projects/plugins
script/plugin install acts_as_attachment

  2. Create a model for storing photos

    3. script/generate attachment_model photo

    edit the generated migration

    
class CreatePhotos < ActiveRecord::Migration
  def self.up
    create_table :photos do |t|
      t.column "coffee_house_id", :integer, :null => false
      t.column "content_type", :string
      t.column "filename", :string     
      t.column "size", :integer
      
      # used with thumbnails, always required
      t.column "parent_id",  :integer 
      t.column "thumbnail", :string
      
      # required for images only
      t.column "width", :integer  
      t.column "height", :integer

      # required for db-based files only
      #t.column "db_file_id", :integer
    end

    # only for db-based files
    # create_table :db_files, :force => true do |t|
    #      t.column :data, :binary
    # end
  end

  def self.down
    drop_table :photos
    
    # only for db-based files
    # drop_table :db_files
  end
end

    run migration

    rake db:migrate

    edit the generated model

    class Photo < ActiveRecord::Base
  belongs_to :coffee_house
  acts_as_attachment :storage => :file_system, :content_type => :image, :thumbnails => {:normal => '300', 'thumb' => '75'}
  validates_as_attachment
end

  3. Create controller actions and views

    4. add actions to coffee_house_controller

    
  def new_photo
    @photo = Photo.new(:coffee_house_id=>params[:id])
  end

  def create_photo
    @photo = Photo.new(params[:photo])
    if @photo.save
      redirect_to :action => 'show', :id => @photo.coffee_house_id
    else
      render :action => 'new_photo'
    end
  end

  def destroy_photo
    @photo = Photo.find_by_id(params[:id])
    redirect_to :action => 'index' and return unless @photo
    @coffee_house = @photo.coffee_house
    @photo.destroy
    render :action => 'show'
  end

    GETs should be safe - update for new actions (find this snippet in coffee_house_controller.rb and add the bolded action names)

    
  # GETs should be safe (see http://www.w3.org/2001/tag/doc/whenToUseGet.html)
  verify :method => :post, :only => [ :destroy, :create, :update, :create_photo, :destroy_photo ],
         :redirect_to => { :action => :list }

    create view in app/views/coffee_house/new_photo.rhtml

    
<h1>New photo</h1>
<%= error_messages_for :photo %>
<% form_for :photo, :url => { :action => 'create_photo' }, :html => { :multipart => true } do |f| -%>
  <p><%= f.hidden_field :coffee_house_id %></p>
  <p><%= f.file_field :uploaded_data %></p>
  <p><%= submit_tag :Create %></p>
<% end -%>

  4. Integrate with the CoffeeHouse application

    5. Add relation to app/models/coffee_house.rb

    has_many :photos, :dependent => :destroy

    Add a gallery and new photo link to app/views/coffee_house/show.rhtml

    
<% for column in CoffeeHouse.content_columns %>
<p>
  <%= column.human_name %>: <%=h @coffee_house.send(column.name) %>
</p>
<% end %>

<% for photo in @coffee_house.photos -%>
  <p><%= photo.filename %></p>
  <%= image_tag photo.public_filename('thumb') %>
  <%= image_tag photo.public_filename, :size => photo.image_size %>
<% end -%>

<p><%= link_to 'Add photo', :action => 'new_photo', :id => @coffee_house %></p>


<%= link_to 'Edit', :action => 'edit', :id => @coffee_house %> |
<%= link_to 'Back', :action => 'list' %>

  5. File storage

    • create directory public/photos
    • make it recursively writeable for the web server

  6. RMagick integration

    7. add at the end of config/environment.rb: require 'RMagick'