rails开发利器：视频播放插件plugin（如何开发一个简单的插件）

1.  For:　rails2.3.8  
   因为我的项目是基于rails2.3.8的，以后在做rails3.0的
2. plugin的名称是 video_player, 新建plugin
   

   ruby  script/generate plugin video_player --with-generator

   
   
3. 重新组织我的文件目录
   新建video_player和rails文件夹，新建rails/init.rb文件
   

   mkdir railsmkdir lib/video_playertouch rails/init.rb

   
   修改 rails/init.rb

   require 'video_player'

   
   删除多余的文件

    rm -rf init.rb install.rb

4. 整理一下我的思路：
   4.1 我需要新建一个helper,用于显示flash video, 而且能分直播和非直播的模式
   4.2 我需要新建一个rake task,用于资源的复制
5. 开发helper方法
   新建lib/app/helpers/video_player_helper.rb文件
   

   module VideoPlayerHelper   def video_player(url_bad='',live=true,width=500, height=400)    flash_url_bad = "http://#{request.env["HTTP_HOST"]}/player.swf"    flash_url = flash_url_bad    player = "<object width='#{width}' height='#{height}'>"    player += '<param value="transparent" name="wmode"></param>'    player +=  "<param value='#{flash_url}' name='movie'></param>"    url = URI.escape(url_bad, Regexp.new("[^#{URI::PATTERN::UNRESERVED}]"))    if live      player += "<param value='src=#{url}&streamType=live&autoRewind=true&autoPlay=true&bufferingOverlay=false&autoDynamicStreamSwitch=false&optimizeInitialIndex=false&bufferTime=0&initialBufferTime=0&expandedBufferTime=0&dynamicStreamBufferTime=0&dvrBufferTime=0&dvrDynamicStreamingBufferTime=0&liveBufferTime=0&liveDynamicStreamingBufferTime=0&minContinuousPlaybackTime=0' name='flashvars'> </param> "    else      player += "<param value='src=#{url}&autoRewind=true&autoPlay=true' name='flashvars'> </param>"    end    player += "<param value='true' name='allowFullScreen'></param>            <param value='always' name='allowscriptaccess'></param>            <embed width='#{width}' height='#{height}' wmode='transparent'"    if live      player += "flashvars='src=#{url}&streamType=live&autoRewind=true&autoPlay=true&bufferingOverlay=false&autoDynamicStreamSwitch=false&optimizeInitialIndex=false&bufferTime=0&initialBufferTime=0&expandedBufferTime=0&dynamicStreamBufferTime=0&dvrBufferTime=0&dvrDynamicStreamingBufferTime=0&liveBufferTime=0&liveDynamicStreamingBufferTime=0&minContinuousPlaybackTime=0'"    else      player += "flashvars='src=#{url}&autoRewind=true&autoPlay=true'"    end    player += " allowfullscreen='true'  allowscriptaccess='always'  type='application/x-shockwave-flash'        src='#{flash_url}'> </embed></object>"    return player  endend

   
   修改video_player.rb文件，将helper加入application中

   %w{ helpers }.each do |dir|  path = File.join(File.dirname(__FILE__), 'app', dir)  $LOAD_PATH << path  ActiveSupport::Dependencies.load_paths << path  ActiveSupport::Dependencies.load_once_paths.delete(path)end if defined?(ActionView::Base)  ActionView::Base.send :include, VideoPlayerHelperend

   
   
   
6. 新建一个rake,用于复制player.swf到Public目录
   

   require 'fileutils'include FileUtils::Verbosedesc "copy player.swf to public dir"task :copy_video_player do  play_swf = File.join(File.dirname(__FILE__),"player.swf")  cp(play_swf, File.join(RAILS_ROOT, "public"))end

7. 代码地址
   https://github.com/chucai/videoplayer