看起来根据 CORS 规范,GET 和 POST 请求应该透明地遵循 302 重定向。但 Chrome 正在取消我的请求。
这是执行请求的 JS:
var r = new XMLHttpRequest();
r.open('GET', 'https://dev.mysite.com/rest', true);
r.send();
这是应该发生的事情:
- 客户端:对 /rest 的 XHR POST 请求
- 服务器:响应 HTTP 302 重定向到 /rest/
- 客户:遵循该重定向
但是在第 2 步之后,Chrome 会取消该请求。如果没有 HTTP 302,请求将完美运行。我已经证实了这一点。
当请求运行时,我可以在 Chrome 的网络面板中看到只有一个 XHR——一个取消的 POST 请求,没有响应标头或响应正文。
使用 Chrome 的 net-internals 工具调试,我看到服务器发送了一个响应,然后请求被取消。这是请求的输出:
79295: URL_REQUEST
https://dev.mysite.com/rest
Start Time: 2013-08-30 12:41:11.637
t=1377880871637 [st= 0] +REQUEST_ALIVE [dt=13455]
t=1377880871638 [st= 1] URL_REQUEST_BLOCKED_ON_DELEGATE [dt=1]
--> delegate = "extension Adblock Plus"
t=1377880871639 [st= 2] +URL_REQUEST_START_JOB [dt=13453]
--> load_flags = 143540480 (DO_NOT_SAVE_COOKIES | DO_NOT_SEND_AUTH_DATA | DO_NOT_SEND_COOKIES | ENABLE_LOAD_TIMING | MAYBE_USER_GESTURE | REPORT_RAW_HEADERS | VERIFY_EV_CERT)
--> method = "POST"
--> priority = 2
--> upload_id = "0"
--> url = "https://dev.mysite.com/rest"
t=1377880871639 [st= 2] HTTP_CACHE_GET_BACKEND [dt=0]
t=1377880871639 [st= 2] +HTTP_STREAM_REQUEST [dt=7]
t=1377880871646 [st= 9] HTTP_STREAM_REQUEST_BOUND_TO_JOB
--> source_dependency = 79296 (HTTP_STREAM_JOB)
t=1377880871646 [st= 9] -HTTP_STREAM_REQUEST
t=1377880871646 [st= 9] +HTTP_TRANSACTION_SEND_REQUEST [dt=0]
t=1377880871646 [st= 9] HTTP_TRANSACTION_SEND_REQUEST_HEADERS
--> GET /facultyportfolio-rest HTTP/1.1
Host: dev.liberty.edu
Connection: keep-alive
Content-Length: 46
Origin: http://localhost:8080
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/29.0.1547.62 Safari/537.36
Content-Type: application/json; charset=UTF-8
Accept: */*
Referer: http://localhost:8080/ajaxtest.html
Accept-Encoding: gzip,deflate,sdch
Accept-Language: en-US,en;q=0.8
t=1377880871646 [st= 9] HTTP_TRANSACTION_SEND_REQUEST_BODY
--> did_merge = true
--> is_chunked = false
--> length = 46
t=1377880871646 [st= 9] -HTTP_TRANSACTION_SEND_REQUEST
t=1377880871646 [st= 9] +HTTP_TRANSACTION_READ_HEADERS [dt=1001]
t=1377880871646 [st= 9] HTTP_STREAM_PARSER_READ_HEADERS [dt=1000]
t=1377880872646 [st= 1009] HTTP_TRANSACTION_READ_RESPONSE_HEADERS
--> HTTP/1.1 302 Found
Date: Fri, 30 Aug 2013 16:41:11 GMT
Server: Apache/2
Access-Control-Allow-Origin: http://localhost:8080
Access-Control-Allow-Credentials: true
Location: https://dev.mysite.com/rest/
Content-Language: en-US
Vary: Accept-Encoding,User-Agent
Content-Encoding: gzip
Content-Length: 20
Connection: close
Content-Type: text/plain; charset=UTF-8
t=1377880872647 [st= 1010] -HTTP_TRANSACTION_READ_HEADERS
t=1377880872647 [st= 1010] +URL_REQUEST_BLOCKED_ON_DELEGATE [dt=12445]
t=1377880885091 [st=13454] CANCELLED
t=1377880885092 [st=13455] -URL_REQUEST_START_JOB
--> net_error = -3 (ERR_ABORTED)
t=1377880885092 [st=13455] -REQUEST_ALIVE
最后,您可以看到“已取消”,因为“URL_REQUEST_BLOCKED_ON_DELEGATE”。我不知道那是什么意思。但同样,如果没有 HTTP 302 重定向,则不会发生错误。
有谁知道是什么导致 Chrome 取消此请求?