我经常喜欢清理通过Airbrake出现的500个错误。我正在生产中运行一个Rails 4.2.4站点，我发现一个反复出现的错误非常令人困惑。
错误为：
Missing partial shared/_rhs with {:locale=>[:en], :formats=>["xE2x80x8B/xE2x80x8B"], :variants=>[], :handlers=>[:erb, :builder, :raw, :ruby, :coffee, :haml, :jbuilder]}.
查看Airbrake的env部分以查找错误，相关部分似乎是：
"action_dispatch.request.accepts": "["\xE2\x80\x8B/\xE2\x80\x8B"]",
"action_dispatch.request.content_type": "",
"action_dispatch.request.flash_hash": "",
"action_dispatch.request.formats": "["\xE2\x80\x8B/\xE2\x80\x8B"]",
看起来浏览器(自称Chrome)要求使用未识别的格式，但我不知道它为什么会这样做。它似乎只要求头部。
我可以忽略它，但如果有人对它最初发生的原因有任何想法，我会感兴趣的。
完整的env(删除了标识内容项)是：
{
"DOCUMENT_ROOT": "[******]",
"HTTPS": "on",
"HTTP_ACCEPT": "/",
"HTTP_ACCEPT_ENCODING": "gzip,deflate,sdch",
"HTTP_ACCEPT_LANGUAGE": "en-US,en;q=0.8",
"HTTP_CACHE_CONTROL": "no-cache",
"HTTP_CONNECTION": "keep-alive",
"HTTP_HOST": "[******]",
"HTTP_PRAGMA": "no-cache",
"HTTP_USER_AGENT": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_3) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/50.0.2661.49 Safari/537.36",
"ORIGINAL_FULLPATH": "[******]",
"ORIGINAL_SCRIPT_NAME": "",
"PASSENGER_APP_ENV": "live",
"PASSENGER_APP_TYPE": "rack",
"PASSENGER_SHOW_VERSION_IN_HEADER": "false",
"PATH_INFO": "[******]",
"QUERY_STRING": "",
"REMOTE_ADDR": "[******]",
"REMOTE_PORT": "47888",
"REQUEST_METHOD": "HEAD",
"REQUEST_URI": "[******]",
"ROUTES_40753200_SCRIPT_NAME": "",
"ROUTES_48254480_SCRIPT_NAME": "",
"SCGI": "1",
"SCRIPT_NAME": "",
"SERVER_ADDR": "[******]",
"SERVER_NAME": "[******]",
"SERVER_PORT": "443",
"SERVER_PROTOCOL": "HTTP/1.1",
"SERVER_SOFTWARE": "nginx/1.6.0",
"action_dispatch.cookies_digest": "",
"action_dispatch.cookies_serializer": "",
"action_dispatch.parameter_filter": "["password"]",
"action_dispatch.redirect_filter": "[]",
"action_dispatch.remote_ip": "[******]",
"action_dispatch.request.accepts": "["\xE2\x80\x8B/\xE2\x80\x8B"]",
"action_dispatch.request.content_type": "",
"action_dispatch.request.flash_hash": "",
"action_dispatch.request.formats": "["\xE2\x80\x8B/\xE2\x80\x8B"]",
"action_dispatch.request.parameters": {
"action": "show_by_tag_and_slug",
"controller": "[******]",
"slug": "[******]",
"tag": "[******]"
},
"action_dispatch.request.path_parameters": {
"action": "show_by_tag_and_slug",
"controller": "[******]",
"slug": "[******]",
"tag": "[******]"
},
"action_dispatch.request.query_parameters": "",
"action_dispatch.request.request_parameters": "",
"action_dispatch.request_id": "f120141c-58e6-4429-ad98-1ab352f1c7ce",
"action_dispatch.show_detailed_exceptions": "false",
"action_dispatch.show_exceptions": "true",
"newrelic.transaction_started": "true",
"preview_manager": "#<Preview::Manager:0x007fa334e8eca0>",
"rack.hijack": "#<Proc:0x007fa34ee79020@/home/release/.rvm/gems/ruby-2.2.2/gems/passenger-4.0.53/lib/phusion_passenger/rack/thread_handler_extension.rb:69 (lambda)>",
"rack.hijack?": "true",
"rack.multiprocess": "true",
"rack.multithread": "false",
"rack.request.query_hash": "",
"rack.request.query_string": "",
"rack.run_once": "false",
"rack.url_scheme": "https",
"rack.version": "["1", "2"]",
"warden": "Warden::Proxy:70169690063580 @config={:default_scope=>:user, :scope_defaults=>{}, :default_strategies=>{:user=>[:rememberable, :database_authenticatable]}, :intercept_401=>false, :failure_app=>#<Devise::Delegator:0x00000004e859a0>}"
}
字符xE2x80x8B似乎是Unicode中的零宽度空格字符。这就是为什么，如果您将字符串粘贴到ruby控制台，您将得到以下内容：
"xE2x80x8B/xE2x80x8B"
# => "/"
即，看起来只是斜线/，但实际上被两个零宽度空间包围。我不知道为什么浏览器会在Accepts标头中发送这样的字符，这可能是浏览器中的错误，甚至是某种攻击。。。