Ocelot Request headers must contain only ASCII characters

小渣渣

回顾：

Ocelot 系列（一）ASP.NET Core 网关实战
https://www.itsvse.com/thread-9284-1-1.html

启动 ocelot 网关，访问接口报错如下：

Status Code: 502; Bad Gateway                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 

项目是 ASP.NET Core 3.1，Ocelot 使用的版本是 16.0.1

info: Ocelot.RateLimit.Middleware.ClientRateLimitMiddleware[0]
      requestId: 0HM8JAOKL2C09:00000006, previousRequestId: no previous request id, message: EndpointRateLimiting is not enabled for /{url}
warn: Ocelot.Responder.Middleware.ResponderMiddleware[0]
      requestId: 0HM8JAOKL2C09:00000006, previousRequestId: no previous request id, message: Error Code: ConnectionToDownstreamServiceError Message: Error connecting to downstream service, exception: System.Net.Http.HttpRequestException: Request headers must contain only ASCII characters.
         at System.Net.Http.HttpConnection.WriteStringAsync(String s)
         at System.Net.Http.HttpConnection.WriteHeadersAsync(HttpHeaders headers, String cookiesFromContainer)
         at System.Net.Http.HttpConnection.SendAsyncCore(HttpRequestMessage request, CancellationToken cancellationToken)
         at System.Net.Http.HttpConnectionPool.SendWithNtConnectionAuthAsync(HttpConnection connection, HttpRequestMessage request, Boolean doRequestAuth, CancellationToken cancellationToken)
         at System.Net.Http.HttpConnectionPool.SendWithRetryAsync(HttpRequestMessage request, Boolean doRequestAuth, CancellationToken cancellationToken)
         at System.Net.Http.DiagnosticsHandler.SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
         at System.Net.Http.HttpClient.FinishSendAsyncBuffered(Task`1 sendTask, HttpRequestMessage request, CancellationTokenSource cts, Boolean disposeCts)
         at Ocelot.Requester.HttpClientHttpRequester.GetResponse(HttpContext httpContext) errors found in ResponderMiddleware. Setting error response for request path:/test1/home/index, request method: GET

使用 Fiddler 抓包如下，发现 cookie 有中文字符串，如下：

Host: localhost:5002
Connection: keep-alive
Cache-Control: max-age=0
sec-ch-ua: "Google Chrome";v="89", "Chromium";v="89", ";Not A Brand";v="99"
sec-ch-ua-mobile: ?0
Upgrade-Insecure-Requests: 1
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/89.0.4389.114 Safari/537.36
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.9
Sec-Fetch-Site: none
Sec-Fetch-Mode: navigate
Sec-Fetch-User: ?1
Sec-Fetch-Dest: document
Accept-Encoding: gzip, deflate, br
Accept-Language: zh-CN,zh;q=0.9
Cookie: aaa=测试

浏览器写入 cookie 代码（以下代码 value 未做转义）可以复现该问题：

登录可见。

浏览器console写入cookie
https://www.itsvse.com/thread-4682-1-1.html

尝试清空 cookie 缓存，网关恢复正常，如下图：



附 Ocelot 执行中间件顺序如下：

PreErrorResponderMiddleware
PreAuthenticationMiddleware
AuthenticationMiddleware
PreAuthorisationMiddleware
AuthorisationMiddleware       
PreQueryStringBuilderMiddleware


（完）