README.markdown

Store file uploads in the database

This gem allows to store carrierwave uploads in the database, eg. on platforms with ephemeral filesystems like Heroku.

Installation

# In: Gemfile
gem 'carrierwave-blob', git: "https://gist.github.com/f1dc8c75d67b92b23a55.git"

Usage

1. Setup your uploader to use the blob storage:

# In: app/uploaders/picture_uploader.rb
storage CarrierWave::Storage::Blob

2. Generate a migration for your model:

rails generate carrier_wave_blob_migration Idea

3. Execute the migrations:

rake db:migrate

---

Created during RailsGirls Prague

carrierwave-blob-generator.rb

class CarrierWaveBlobMigrationGenerator < Rails::Generators::NamedBase
  desc    "Creates a migration to update column type to text"
  argument :fieldname, default: 'picture'

  check_class_collision

  def create_migration_file
    migration_nr = ActiveRecord::Migration.next_migration_number(Time.now.to_i)
    create_file "db/migrate/#{migration_nr}_update_#{name.downcase}_#{fieldname.downcase}_column.rb",
    <<-CONTENT.gsub(/^\s{6}/, '')
      class Update#{name.capitalize}#{fieldname.capitalize}Column < ActiveRecord::Migration
        def change
          change_column :#{name.tableize}, :#{fieldname}, :text, limit: nil
        end
      end

    CONTENT
    say "Don't forget to run `rake db:migrate`!", :yellow
  end
end

carrierwave-blob.gemspec

# -*- encoding: utf-8 -*-

Gem::Specification.new do |s|
  s.name        = "carrierwave-blob"
  s.version     = "0.0.1"
  s.platform    = Gem::Platform::RUBY
  s.summary       = "BLOB support for Carrierwave"
  s.authors       = [ 'Karel Minarik', 'Vojtech Hyza' ]
  s.email         = [ 'karmi@karmi.cz', 'vhyza@vhyza.eu' ]

  s.files         = `git ls-files`.split("\n")
  s.test_files    = `git ls-files -- {test,spec,features}/*`.split("\n")
  s.executables   = `git ls-files -- bin/*`.split("\n").map{ |f| File.basename(f) }

  s.require_paths = ["."]

  s.add_dependency "carrierwave"
end

carrierwave-blob.rb

# encoding: utf-8

module CarrierWave
  module Storage

    class Blob < Abstract
      class Content
        def initialize(content)
          @content = content
        end

        def url(options={})
          @content
        end

        def to_s
          @content
        end
      end

      def store!(file)
        # require "pry"; binding.pry
        type = uploader.file.content_type
        blob = Base64.encode64(self.uploader.file.read)
        uploader.model.update_columns self.uploader.mounted_as => "data:#{type};base64,#{blob}"
      end

      def retrieve!(identifier=nil)
        Content.new uploader.model.read_attribute(self.uploader.mounted_as)
      end
    end

  end
end

class CarrierWaveBlobRailtie < Rails::Railtie
  generators do
    require 'carrierwave-blob-generator'
  end
end