rails 文件上传

注: 本片文章参考 redmine

1.
rails upload_file
2.  database.yml

ruby 代码

development:
  adapter: sqlite3
  dbfile: db/dev.db

test:
  adapter: sqlite3
  dbfile: db/test.db

production:
  adapter: sqlite3
  dbfile: db/prod.db

3.
ruby script/generate model attachment filename:string disk_filename:string content_type:string created_on:datetime downloads:integer filesize:integer
4.
rake db:migrate
5.
ruby script\generate controller attachment show upload

6.vi app\controllers\attachment_controller.rb

ruby 代码

class AttachmentController < ApplicationController
  def show
  end

  def upload
   
  end
 
  def create
    Attachment.create(:file => params[:file])
    redirect_to :action => "show"
  end
 
  def download
    @attachment = Attachment.find(params[:id])
    @attachment.increment_download

    send_file @attachment.diskfile, :filename => @attachment.filename
  end
end

7.vi app\views\attachment\show.rhtml

xml 代码

<table>
  <thead>
    <th>Filename</th>
    <th>Disk_filename</th>
    <th>Content_type</th>
    <th>Downloads</th>
    <th>Filesize</th>
  </thead>
  <tbody>
    <% Attachment.find(:all).each do |a| %>
    <tr>
    <td><a href="/attachment/download/<%= a.id%>"><%= a.filename %></a></td>
    <td><%= a.disk_filename%></td>
    <td><%= a.content_type%></td>
    <td><%= a.downloads%></td>
    <td><%= a.filesize%></td>
  </tr>
    <% end %>
  </tbody>
</table>

<hr />
<a href=/attachment/upload>upload</a>

8.vi app\views\attachment\upload.rhtml

xml 代码

<form action="/attachment/create/1" class="tabular" enctype="multipart/form-data" method="post">
<input id="file" name="file" size="30" type="file" />
<input name="commit" type="submit" value="Create" />
<!---->form>

9.vi app\models\attachment.rb

ruby 代码

class Attachment < ActiveRecord::Base
  validates_presence_of :filename

  cattr_accessor :storage_path
  @@storage_path = "#{RAILS_ROOT}/files"

  def validate
    errors.add_to_base :too_long if self.filesize > 5140.kilobytes
  end

    def file=(incomming_file)
        unless incomming_file.nil?
            @temp_file = incomming_file
            if @temp_file.size > 0
                self.filename = sanitize_filename(@temp_file.original_filename)
                self.disk_filename = DateTime.now.strftime("%y%m%d%H%M%S") + "_" + self.filename
                self.content_type = @temp_file.content_type
                self.filesize = @temp_file.size
            end
        end
    end

    def file
     nil
    end

    def before_save
        if @temp_file && (@temp_file.size > 0)
            logger.debug("saving '#{self.diskfile}'")
            File.open(diskfile, "wb") do |f|
                f.write(@temp_file.read)
            end
        end
    end

    def after_destroy
        if self.filename?
            File.delete(diskfile) if File.exist?(diskfile)
        end
    end

    # Returns file's location on disk
    def diskfile
        "#{@@storage_path}/#{self.disk_filename}"
    end

  def increment_download
    increment!(:downloads)
  end

    def self.most_downloaded
        find(:all, :limit => 5, :order => "downloads DESC")
    end

  private
  def sanitize_filename(value)
      just_filename = value.gsub(/^.*(\\|\/)/, '')
      @filename = just_filename.gsub(/[^\w\.\-]/,'_')
  end

end

10.
在根目录创建文件夹 files