Watarase¶ ↑

Watarase is a rails plugin for Image Upload.

Images are stored into the database as binary data. This plugin is inteded to be handled as a small image of the icon.

ImageMagick must be installed.

Add to Gemfile following

gem 'watarase'

Any model of the target is present is expected.

example

rails generate scaffold user username:string email:string

That model is the image handler.

Generate image holder. This is a model that is made separately.

rails generate watarase:uploader user

The generator made UserImageHolder the model class and the migration file.

Example of migration file is following.

class CreateUserImageHolders < ActiveRecord::Migration
  def change
    create_table :user_image_holders do |t|
      t.string :user_username
      t.string :filename
      t.string :content_type
      t.binary :image_data
      t.binary :image_thumb

      t.timestamps
    end
  end
end

In this case, the foreign key ‘user_username’ is type :string. It was named {model name}_{pk} automatically.

Define ‘acts_as_image_hander’ into Image handler model (ex. User).

class User
  self.primary_key :username # if this model's PK was 'username'.
  acts_as_image_handler # define image hander
end

Add ‘load_image’ action in ‘config/routes.rb’

resources :users do
  member do
    get 'load_image'
  end
end

Define ‘image_loadable <image_handler>’ definition in controllers.

If you need image caching then, use options caches: and expire_actions:.

class UsersController < ApplicationController
  image_loadable :user, caches: true, expire_actions: [:update], save_actions: [:create, :update]

In this case, action caching enabled, and clearing the cache in update action. The option save_actions is associate image_handler(ex. user) with image_holder(ex. user_image_holder).

def index
  @users = User.all
end

It is a good idea to make the following changes:

def index
  @users = User.all.merge(includes: [:user_image_holder])
end

Examples _form.html.erb for User

<%= form_for(@user) do |f| %>
  <% if @user.errors.any? %>
    <div id="error_explanation">
      <h2><%= pluralize(@user.errors.count, "error") %> prohibited this user from being saved:</h2>

      <ul>
      <% @user.errors.full_messages.each do |msg| %>
        <li><%= msg %></li>
      <% end %>
      </ul>
    </div>
  <% end %>

  <div class="field">
    <%= f.label :username %><br />
    <%= f.text_field :username %>
  </div>
  <div class="field">
    <%= f.label :email %><br />
    <%= f.text_field :email %>
  </div>
  <div class="field">
    <%= f.label :image_file %><br />
    <%= f.file_field :image_file %>
  </div>
  <% unless @user.new_record? %>
        <div class="field">
          <%= f.check_box :remove_image %>
          <%= f.label :remove_image %><br />
        </div>
  <% end %>
  <div class="actions">
    <%= f.submit %>
  </div>
<% end %>

Add file_field form, and check box for remove the image. Parameter name is fixed, :image_file and :remove_image.

Examples image load in index.html.erb

<% @users.each do |user| %>
<tr>
  <td><%= image_tag image_thumb_path user if user.user_image_holder %></td>
  <td><%= user.username %></td>
  <td><%= link_to 'Show', user %></td>
  <td><%= link_to 'Edit', edit_user_path(user) %></td>
  <td><%= link_to 'Destroy', user, method: :delete, data: { confirm: 'Are you sure?' } %></td>
</tr>
<% end %>

* Configuring parameters for plugin settings.
* Secure upload by file extentions.

This project rocks and uses MIT-LICENSE.