Question

我有一个rake任务，从API获取JSON数据，解析它，并将其保存到数据库中：

task :embedly => :environment do
  require 'json'
  require 'uri'
  require 'open-uri'

  Video.all.each do |video|
    json_stream = open("http://api.embed.ly/1/oembed?key=08b652e6b3ea11e0ae3f4040d3dc5c07&url=#{video.video_url}&maxwidth=525")
    ruby_hash = JSON.parse(json_stream.read)
    thumbnail_url = ruby_hash['thumbnail_url']
    embed_code = ruby_hash['html']
    video.update_attributes(:thumbnail_url => thumbnail_url, :embed_code => embed_code)
  end  
end

当我运行rake任务时，我在堆栈跟踪中出现此错误，我不知道是什么导致它：

rake aborted!
404 Not Found
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/open-uri.rb:277:in `open_http'
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/open-uri.rb:616:in `buffer_open'
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/open-uri.rb:164:in `open_loop'
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/open-uri.rb:162:in `catch'
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/open-uri.rb:162:in `open_loop'
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/open-uri.rb:132:in `open_uri'
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/open-uri.rb:518:in `open'
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/open-uri.rb:30:in `open'
/rubyprograms/dreamstill/lib/tasks/tasks.rake:16
/rubyprograms/dreamstill/lib/tasks/tasks.rake:15:in `each'
/rubyprograms/dreamstill/lib/tasks/tasks.rake:15
/Library/Ruby/Gems/1.8/gems/rake-0.8.7/lib/rake.rb:636:in `call'
/Library/Ruby/Gems/1.8/gems/rake-0.8.7/lib/rake.rb:636:in `execute'
/Library/Ruby/Gems/1.8/gems/rake-0.8.7/lib/rake.rb:631:in `each'
/Library/Ruby/Gems/1.8/gems/rake-0.8.7/lib/rake.rb:631:in `execute'
/Library/Ruby/Gems/1.8/gems/rake-0.8.7/lib/rake.rb:597:in `invoke_with_call_chain'
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/monitor.rb:242:in `synchronize'

有关问题的任何想法以及如何解决问题？

Answer 1

如果指定的资源（视频/图片）不存在，则embed.ly api返回404。 OpenURI将此作为例外处理。要捕获错误，您可以执行以下操作：

task :embedly => :environment do
  require 'json'
  require 'uri'
  require 'open-uri'

  Video.all.each do |video|
    begin
      json_stream = open("http://api.embed.ly/1/oembed?key=08b652e6b3ea11e0ae3f4040d3dc5c07&url=#{video.video_url}&maxwidth=525")
      ruby_hash = JSON.parse(json_stream.read)
      thumbnail_url = ruby_hash['thumbnail_url']
      embed_code = ruby_hash['html']
      video.update_attributes(:thumbnail_url => thumbnail_url, :embed_code => embed_code)
    rescue OpenURI::HTTPError => ex
      puts "Handle missing video here"
    end 
  end  
end

您还可以在运行任务之前检查视频/网址是否有效。

Answer 2

您不是对video.url <：p>进行网址编码的网址

json_stream = open("...url=#{video.video_url}...")

所以你可能会产生一个错位的URL，api.embed.ly告诉你它找不到它。例如，如果video.video_url为http://a.b?c=d&e=f，那么e=f将被视为http://api.embed.ly/1/oembed的参数，而不是传递给http://a.b。

您可能希望这样做：

require 'cgi'
#...
json_stream = open("...url=#{CGI.escape(video.video_url)}...")

在rake任务中使用open-uri 404错误...导致它的原因是什么？

2 个答案: