has_storage

Organize directories and files, respecting a maximum number of items per directory.

Instalation

1) Install the plugin with script/plugin install git://github.com/fnando/has_storage.git 2) Generate a migration with script/generate migration create_storages and add the following code:

class CreateStorages < ActiveRecord::Migration
  def self.up
    create_table :storages do |t|
      t.string :name, :cluster
    end

    add_index :storages, [:name, :cluster]
  end

  def self.down
    drop_table :storages
  end
end

3) Add the fields attachment_path, attachment_content_type and attachment_size to your model. Just run script/generate migration add_attachment_fields_to_user.

class AddAttachmentFieldsToUser < ActiveRecord::Migration
  def self.up
    add_column :user, :attachment_size, :integer
    add_column :user, :attachment_path, :text
    add_column :user, :attachment_content_type, :string
  end
end

3) Run the migrations with rake db:migrate

Usage

1) Add the method call has_storage to your model.

class User < ActiveRecord::Base
  has_storage

  attr_accessible :avatar_file

  after_save :save_avatar

  private
    def save_avatar
      return if avatar_file.blank?
      write_attribute(:avatar_path, allocate(:avatars, :file => avatar_file, :file_name => "#{id}-avatar.jpg"))
      self.avatar_file = nil
      save
    end
end

2) Available options:

:base_dir  => Where the storage directory will reside. Can be interpolated.
:to        => The output file name. Can be interpolated.
:hex       => Save cluster sloth as hex number
:depth     => Define the cluster structure depth
:max_items => How many items per directory
:processor => An array of processors (see below)

To remove any saved file, just add after_destroy :destroy_file!. This will update the model if nil values.

Some options can be interpolated, like :base_dir and :to. This means that you can set attributes/methods from the instance object to build your path.

has_storage :base_dir => ":rails_root/storage", :to => ":user_id-:uid.:extension"

The option above will set a final path like {Rails.root}/storage/1/200/400/500-abcefghij.pdf. Here's the recognized interpolation placeholders:

:rails_root => The value from RAILS_ROOT constant
:storage_name => The class name using :tableize method
:base_name  => The :from file name without the extension
:name       => The :from file name with the extension
:extension  => The extension from the file defined by :from

The best way of defining the path is to set the path that can be changed as the :base_dir and to put the rest in the :to path. Just make sure the base_dir do not use any value from the instance.

has_storage :base_dir => ":rails_root/storage",
  :to => ":storage_name/:id-:base_name.:extension"

You can apply post processors. Just define a new class like

class SimplesIdeias::Storages::Processor::Ocr
  def initialize(options)  
  end

  def run
  end
end

The ActiveRecord instance will respond to a file attribute; is this attribute that you have to set the file

@user.file = params[:avatar]
@user.file = "/tmp/avatar.jpg"
@user.file = File.open("/tmp/avatar.jpg", "rb")

NOTE: The master branch has a new implemention; for the old one, use the tag stable-1.

Copyright (c) 2007-2008 Nando Vieira, released under the MIT license