google-chrome - Chrome 在 HTTP 302 重定向时取消 CORS XHR

Question

看起来像根据CORS Spec 、GET 和 POST 请求应透明地遵循 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();

应该发生以下情况:

1. 客户端:XHR POST 请求到/rest
2. 服务器:响应 HTTP 302 重定向至/rest/
3. 客户端:遵循该重定向

但在第 2 步之后，Chrome 会取消该请求。如果没有 HTTP 302，该请求将完美运行。我已经确认了这一点。

当请求运行时，我在 Chrome 的网络面板中只能看到一个 XHR——一个取消的 POST 请求，没有响应 header 或响应正文。

使用Chrome的net-internals工具进行调试，我看到服务器发送了响应，之后请求被取消。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”。我不知道这意味着什么。但同样，如果没有 HTTP 302 重定向，则不会发生错误。

有人知道是什么原因导致 Chrome 取消此请求吗？

Answer 1

这里的答案是混合的，暗示了代码中的某些设置等，这可能会解决 CORS 的重定向问题，但 CORS 规范明确指定了此类 CORS 重定向何时会失败/通过:根据规范，浏览器应该

1. 如果对重定向资源的请求不需要飞行前检查(例如没有自定义 header 的简单 CORS 请求)，则允许 3XX 重定向。请参阅https://www.w3.org/TR/cors/#simple-cross-origin-request-0

If the manual redirect flag is unset and the response has an HTTP status code of 301, 302, 303, 307, or 308 Apply the redirect steps

如果对重定向资源的请求需要飞行前检查，则不允许 3XX 重定向。请参阅https://www.w3.org/TR/cors/#cross-origin-request-with-preflight-0

If the response has an HTTP status code of 301, 302, 303, 307, or 308 Apply the cache and network error steps.

我在 github 存储库中探索了各种 CORS 场景:https://github.com/monmohan/cors-experiment .

重定向失败的这个特定问题也可以通过此处的 bundle 轻松地单独重现:https://github.com/monmohan/cors-experiment/tree/master/issue