作业无法加载：未初始化的常量Syck :: Syck

我在后台使用延迟作业（collectiveideas fork）运行方法

我正在运行的方法如下所示，它取出了isbn的价格：

def update_prices(isbn13) @amazon = Nokogiri::XML(open("http://www.amazon.com/s/?url=search-alias%3Daps&field-keywords=#{isbn13}")) price = @amazon.search('span.listprice').first.text.gsub('$', '') book = Book.find_by_isbn13(isbn13) book.update_attribute(:amazon_us_price, price) end handle_asynchronously :update_prices 

现在，当我运行此作业时，作业将添加到数据库中，但在运行时遇到错误。 错误是非常大的，但我认为它的要点来自第一行：作业未能加载：未初始化的常量Syck :: Syck。

 {Job failed to load: uninitialized constant Syck::Syck. Handler: "--- !ruby/struct:Delayed::PerformableMethod object: &id005 !ruby/object:BooksController _action_name: show _config: !omap [] _env: &id001 GATEWAY_INTERFACE: CGI/1.1 PATH_INFO: /books/9780425160985 QUERY_STRING: \"\" REMOTE_ADDR: 127.0.0.1 REMOTE_HOST: localhost REQUEST_METHOD: GET REQUEST_URI: http://localhost:3000/books/9780425160985 SCRIPT_NAME: \"\" SERVER_NAME: localhost SERVER_PORT: \"3000\" SERVER_PROTOCOL: HTTP/1.1 SERVER_SOFTWARE: WEBrick/1.3.1 (Ruby/1.9.2/2010-08-18) HTTP_HOST: localhost:3000 HTTP_CONNECTION: keep-alive HTTP_REFERER: http://localhost:3000/books/search?utf8=%E2%9C%93&keywords=hornets+nest&commit=Search HTTP_ACCEPT: application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5 HTTP_USER_AGENT: Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10_6_6; en-US) AppleWebKit/534.13 (KHTML, like Gecko) Chrome/9.0.597.107 Safari/534.13 HTTP_ACCEPT_ENCODING: gzip,deflate,sdch HTTP_ACCEPT_LANGUAGE: en-US,en;q=0.8 HTTP_ACCEPT_CHARSET: ISO-8859-1,utf-8;q=0.7,*;q=0.3 HTTP_COOKIE: _bookcloud_session=BAh7B0kiD3Nlc3Npb25faWQGOgZFRiIlMTNkZWFlYTdiYjVjN2IzZDAyOTU1MDc1NTc1ZDJlZDBJIhBfY3NyZl90b2tlbgY7AEZJIjFrUHJoT0RlZmZoSzIrSVdFdFJNbGxMckxENEZnMTM1STZuQUJCdHJuak1BPQY7AEY%3D--c2b7958a5461253129b6d363e3d547bd44c83f9d rack.version: - 1 - 1 rack.input: !ruby/object:StringIO {} rack.errors: !ruby/object:IO {} rack.multithread: false rack.multiprocess: false rack.run_once: false rack.url_scheme: http HTTP_VERSION: HTTP/1.1 REQUEST_PATH: / action_dispatch.parameter_filter: - :password action_dispatch.secret_token: ab805f7bf1e681785a2ac4813edc43678cbe855682bc7ca9dc5f2116fc892d8ca41466f9bc261ef4ae15ad83c1c38780780d2f6bfe9c00c14abd68542a535400 action_dispatch.remote_ip: !ruby/object:ActionDispatch::RemoteIp::RemoteIpGetter check_ip_spoofing: true env: *id001 trusted_proxies: !ruby/regexp /(^127\\.0\\.0\\.1$|^(10|172\\.(1[6-9]|2[0-9]|30|31)|192\\.168)\\.)/i rack.session: !map:ActionDispatch::Session::AbstractStore::SessionHash session_id: 13deaea7bb5c7b3d02955075575d2ed0 _csrf_token: kPrhODeffhK2+IWEtRMllLrLD4Fg135I6nABBtrnjMA= rack.session.options: !map:ActionDispatch::Session::AbstractStore::OptionsHash :path: / :domain: :expire_after: :secure: false :httponly: true :id: 13deaea7bb5c7b3d02955075575d2ed0 rack.request.cookie_string: _bookcloud_session=BAh7B0kiD3Nlc3Npb25faWQGOgZFRiIlMTNkZWFlYTdiYjVjN2IzZDAyOTU1MDc1NTc1ZDJlZDBJIhBfY3NyZl90b2tlbgY7AEZJIjFrUHJoT0RlZmZoSzIrSVdFdFJNbGxMckxENEZnMTM1STZuQUJCdHJuak1BPQY7AEY%3D--c2b7958a5461253129b6d363e3d547bd44c83f9d rack.request.cookie_hash: _bookcloud_session: BAh7B0kiD3Nlc3Npb25faWQGOgZFRiIlMTNkZWFlYTdiYjVjN2IzZDAyOTU1MDc1NTc1ZDJlZDBJIhBfY3NyZl90b2tlbgY7AEZJIjFrUHJoT0RlZmZoSzIrSVdFdFJNbGxMckxENEZnMTM1STZuQUJCdHJuak1BPQY7AEY=--c2b7958a5461253129b6d363e3d547bd44c83f9d action_dispatch.cookies: !map:ActionDispatch::Cookies::CookieJar _bookcloud_session: BAh7B0kiD3Nlc3Npb25faWQGOgZFRiIlMTNkZWFlYTdiYjVjN2IzZDAyOTU1MDc1NTc1ZDJlZDBJIhBfY3NyZl90b2tlbgY7AEZJIjFrUHJoT0RlZmZoSzIrSVdFdFJNbGxMckxENEZnMTM1STZuQUJCdHJuak1BPQY7AEY=--c2b7958a5461253129b6d363e3d547bd44c83f9d action_dispatch.request.unsigned_session_cookie: session_id: 13deaea7bb5c7b3d02955075575d2ed0 _csrf_token: kPrhODeffhK2+IWEtRMllLrLD4Fg135I6nABBtrnjMA= action_dispatch.request.path_parameters: :controller: books :action: show :isbn13: \"9780425160985\" action_controller.instance: *id005 action_dispatch.request.content_type: action_dispatch.request.request_parameters: !map:ActiveSupport::HashWithIndifferentAccess {} rack.request.query_string: \"\" rack.request.query_hash: {} action_dispatch.request.query_parameters: !map:ActiveSupport::HashWithIndifferentAccess {} action_dispatch.request.parameters: &id002 !map:ActiveSupport::HashWithIndifferentAccess controller: books action: show isbn13: \"9780425160985\" action_dispatch.request.formats: - !ruby/object:Mime::Type string: text/html symbol: :html synonyms: - application/xhtml+xml _headers: Content-Type: text/html _params: *id002 _request: &id003 !ruby/object:ActionDispatch::Request env: *id001 filtered_parameters: controller: books action: show isbn13: \"9780425160985\" fullpath: /books/9780425160985 method: GET request_method: GET _response: !ruby/object:ActionDispatch::Response blank: false block: body: [] cache_control: {} cookie: [] etag: header: {} length: 0 request: *id003 sending_file: false status: 200 writer: !ruby/object:Proc {} _response_body: _status: 200 action_has_layout: true author: Patricia Daniels Cornwell book: !ruby/ActiveRecord:Book attributes: isbn13: \"9780425160985\" title: Hornet's Nest author: Patricia Daniels Cornwell price: created_at: &id004 2011-03-03 10:41:27.757528 Z updated_at: *id004 amazon_us_price: id: 38 lookup: !ruby/object:Nokogiri::XML::Document decorators: errors: [] node_cache: - !ruby/object:Nokogiri::XML::Element {} - !ruby/object:Nokogiri::XML::Element {} - !ruby/object:Nokogiri::XML::Element {} lookup_context: !ruby/object:ActionView::LookupContext details: :handlers: - :erb - :rjs - :builder - :rhtml - :rxml :formats: - :html :locale: - :en - :en details_key: frozen_formats: false skip_default_locale: false view_paths: !seq:ActionView::PathSet - !ruby/object:ActionView::FileSystemResolver cached: {} caching: false path: /Users/nick/Dropbox/rails/bookcloud/app/views title: Hornet's Nest view_context_class: method_name: :update_prices_without_delay args: - \"9780425160985\" " /Users/nick/.rvm/gems/ruby-1.9.2-p0@rorticket/gems/delayed_job-2.1.4/lib/delayed/backend/base.rb:81:in `rescue in payload_object' /Users/nick/.rvm/gems/ruby-1.9.2-p0@rorticket/gems/delayed_job-2.1.4/lib/delayed/backend/base.rb:79:in `payload_object' /Users/nick/.rvm/gems/ruby-1.9.2-p0@rorticket/gems/delayed_job-2.1.4/lib/delayed/backend/base.rb:87:in `invoke_job' /Users/nick/.rvm/gems/ruby-1.9.2-p0@rorticket/gems/delayed_job-2.1.4/lib/delayed/worker.rb:120:in `block (2 levels) in run' /Users/nick/.rvm/rubies/ruby-1.9.2-p0/lib/ruby/1.9.1/timeout.rb:57:in `timeout' /Users/nick/.rvm/gems/ruby-1.9.2-p0@rorticket/gems/delayed_job-2.1.4/lib/delayed/worker.rb:120:in `block in run' /Users/nick/.rvm/rubies/ruby-1.9.2-p0/lib/ruby/1.9.1/benchmark.rb:309:in `realtime' /Users/nick/.rvm/gems/ruby-1.9.2-p0@rorticket/gems/delayed_job-2.1.4/lib/delayed/worker.rb:119:in `run' /Users/nick/.rvm/gems/ruby-1.9.2-p0@rorticket/gems/delayed_job-2.1.4/lib/delayed/worker.rb:177:in `reserve_and_run_one_job' /Users/nick/.rvm/gems/ruby-1.9.2-p0@rorticket/gems/delayed_job-2.1.4/lib/delayed/worker.rb:104:in `block in work_off' /Users/nick/.rvm/gems/ruby-1.9.2-p0@rorticket/gems/delayed_job-2.1.4/lib/delayed/worker.rb:103:in `times' /Users/nick/.rvm/gems/ruby-1.9.2-p0@rorticket/gems/delayed_job-2.1.4/lib/delayed/worker.rb:103:in `work_off' /Users/nick/.rvm/gems/ruby-1.9.2-p0@rorticket/gems/delayed_job-2.1.4/lib/delayed/worker.rb:78:in `block (2 levels) in start' /Users/nick/.rvm/rubies/ruby-1.9.2-p0/lib/ruby/1.9.1/benchmark.rb:309:in `realtime' /Users/nick/.rvm/gems/ruby-1.9.2-p0@rorticket/gems/delayed_job-2.1.4/lib/delayed/worker.rb:77:in `block in start' /Users/nick/.rvm/gems/ruby-1.9.2-p0@rorticket/gems/delayed_job-2.1.4/lib/delayed/worker.rb:74:in `loop' /Users/nick/.rvm/gems/ruby-1.9.2-p0@rorticket/gems/delayed_job-2.1.4/lib/delayed/worker.rb:74:in `start' /Users/nick/.rvm/gems/ruby-1.9.2-p0@rorticket/gems/delayed_job-2.1.4/lib/delayed/tasks.rb:9:in `block (2 levels) in ' /Users/nick/.rvm/gems/ruby-1.9.2-p0@global/gems/rake-0.8.7/lib/rake.rb:636:in `call' /Users/nick/.rvm/gems/ruby-1.9.2-p0@global/gems/rake-0.8.7/lib/rake.rb:636:in `block in execute' /Users/nick/.rvm/gems/ruby-1.9.2-p0@global/gems/rake-0.8.7/lib/rake.rb:631:in `each' /Users/nick/.rvm/gems/ruby-1.9.2-p0@global/gems/rake-0.8.7/lib/rake.rb:631:in `execute' /Users/nick/.rvm/gems/ruby-1.9.2-p0@global/gems/rake-0.8.7/lib/rake.rb:597:in `block in invoke_with_call_chain' /Users/nick/.rvm/rubies/ruby-1.9.2-p0/lib/ruby/1.9.1/monitor.rb:201:in `mon_synchronize' /Users/nick/.rvm/gems/ruby-1.9.2-p0@global/gems/rake-0.8.7/lib/rake.rb:590:in `invoke_with_call_chain' /Users/nick/.rvm/gems/ruby-1.9.2-p0@global/gems/rake-0.8.7/lib/rake.rb:583:in `invoke' /Users/nick/.rvm/gems/ruby-1.9.2-p0@global/gems/rake-0.8.7/lib/rake.rb:2051:in `invoke_task' /Users/nick/.rvm/gems/ruby-1.9.2-p0@global/gems/rake-0.8.7/lib/rake.rb:2029:in `block (2 levels) in top_level' /Users/nick/.rvm/gems/ruby-1.9.2-p0@global/gems/rake-0.8.7/lib/rake.rb:2029:in `each' /Users/nick/.rvm/gems/ruby-1.9.2-p0@global/gems/rake-0.8.7/lib/rake.rb:2029:in `block in top_level' /Users/nick/.rvm/gems/ruby-1.9.2-p0@global/gems/rake-0.8.7/lib/rake.rb:2068:in `standard_exception_handling' /Users/nick/.rvm/gems/ruby-1.9.2-p0@global/gems/rake-0.8.7/lib/rake.rb:2023:in `top_level' /Users/nick/.rvm/gems/ruby-1.9.2-p0@global/gems/rake-0.8.7/lib/rake.rb:2001:in `block in run' /Users/nick/.rvm/gems/ruby-1.9.2-p0@global/gems/rake-0.8.7/lib/rake.rb:2068:in `standard_exception_handling' /Users/nick/.rvm/gems/ruby-1.9.2-p0@global/gems/rake-0.8.7/lib/rake.rb:1998:in `run' /Users/nick/.rvm/gems/ruby-1.9.2-p0@global/gems/rake-0.8.7/bin/rake:31:in `' /Users/nick/.rvm/gems/ruby-1.9.2-p0@global/bin/rake:19:in `load' /Users/nick/.rvm/gems/ruby-1.9.2-p0@global/bin/rake:19:in `' 

知道可能导致错误的原因吗？ 我以前从未听说过Syck。

Answer 1

在boot.rb中包含以下代码行（config \ boot.rb）

 require 'yaml' YAML::ENGINE.yamler= 'syck' 

Answer 2

对于那些不起作用的人，像我一样，我发现包含Psych gem来处理YAML解析修复了这个问题。 请参阅： Delayed_job：作业无法加载：未初始化的常量Syck :: Syck