- html - 出于某种原因,IE8 对我的 Sass 文件中继承的 html5 CSS 不友好?
- JMeter 在响应断言中使用 span 标签的问题
- html - 在 :hover and :active? 上具有不同效果的 CSS 动画
- html - 相对于居中的 html 内容固定的 CSS 重复背景?
这个问题的简短版本是我们看到了典型的 CORS 错误 ( x has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource.
) 但是我们绝对发送了指定的 header 。请求可以开始,但是在 n(模式未确定)时间后,某些(除了 html 文件中引用的随机 1 或 2 个 Assets 之外没有真正的模式)请求将突然开始失败。在硬刷新或禁用缓存时,问题已解决。
我们想知道在这种情况下缓存如何影响 CORS?或者如果问题出在其他地方?
我们看到的是 Assets 在第一个实例中加载良好。
这是浏览器( chrome ,未在其他地方测试)发送到服务器( s3 前面的 cloudfront )的 cURL 表示:
curl -I 'https://assets-frontend.kalohq.ink/style.allapps.add899080acbbeed5bb6a7301d234b65.css' -H 'Referer: https://lystable.kalohq.ink/projects/2180?edit=true' -H 'Origin: https://lystable.kalohq.ink' -H 'DPR: 2' -H 'User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_6) AppleWebKit/537.36 (KHTML, like Gec
HTTP/1.1 200 OK
Content-Type: text/css
Content-Length: 5632
Connection: keep-alive
Date: Wed, 28 Jun 2017 09:23:04 GMT
Access-Control-Allow-Origin: *
Access-Control-Allow-Methods: GET
Access-Control-Max-Age: 3000
Last-Modified: Wed, 28 Jun 2017 09:16:15 GMT
ETag: "ece4babc2509d989254638493ff4c742"
Cache-Control: max-age=31556926
Content-Encoding: gzip
Accept-Ranges: bytes
Server: AmazonS3
Vary: Origin,Access-Control-Request-Headers,Access-Control-Request-Method
Age: 3384
X-Cache: Hit from cloudfront
Via: 1.1 adc13b6f5827d04caa2efba65479257c.cloudfront.net (CloudFront)
X-Amz-Cf-Id: PcC2qL04aC4DPtNuwCudckVNM3QGhz4jiDL10IDkjIBnCOK3hxoMoQ==
Access to CSS stylesheet at 'https://assets-frontend.kalohq.ink/style.allapps.add899080acbbeed5bb6a7301d234b65.css' from origin 'https://kalohq.ink' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'https://kalohq.ink' is therefore not allowed access.
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script
和
link
标签有
crossorigin="anonymous"
.还要注意 preload 和 prefetch 标签。
access-control-max-age
至 -1
这禁用了这个。我们不希望这有任何影响,因为这只会(阅读规范)影响 GET 请求不会发生的预检请求。 Note this solving the issue has now been proved incorrect. See Update 2.
allapps.commons.HASH123.css
在版本 v1 和 v2 之间没有变化,那么我们的想法是我们可以利用浏览器缓存。
<script>
引用的那些 Assets 。和
<link>
标签。
crossorigin="anonymous"
.
.har
file显示此问题发生在用户 session 中。
"url": "https://assets-frontend.kalohq.ink/style.allapps.add899080acbbeed5bb6a7301d234b65.css",
并查看为此 Assets 提出的各种请求。你会看到前几个很好,并且有你期望的标题。最后一次出现(第 32624 行)是失败的一次。
{
"startedDateTime": "2017-06-28T09:40:15.534Z",
"time": 0,
"request": {
"method": "GET",
"url": "https://assets-frontend.kalohq.ink/style.allapps.add899080acbbeed5bb6a7301d234b65.css",
"httpVersion": "unknown",
"headers": [
{
"name": "Referer",
"value": "https://kalohq.ink/account"
},
{
"name": "Origin",
"value": "https://kalohq.ink"
},
{
"name": "DPR",
"value": "2"
},
{
"name": "User-Agent",
"value": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_10_5) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/58.0.3029.110 Safari/537.36"
}
],
"queryString": [],
"cookies": [],
"headersSize": -1,
"bodySize": 0
},
"response": {
"status": 0,
"statusText": "",
"httpVersion": "unknown",
"headers": [],
"cookies": [],
"content": {
"size": 0,
"mimeType": "x-unknown"
},
"redirectURL": "",
"headersSize": -1,
"bodySize": -1,
"_transferSize": 0,
"_error": ""
},
"cache": {},
"timings": {
"blocked": -1,
"dns": -1,
"connect": -1,
"send": 0,
"wait": 0,
"receive": 0,
"ssl": -1
},
"serverIPAddress": "",
"pageref": "page_10"
},
crossorigin="anonymous"
的使用。属性无处不在。到目前为止,我们还没有看到问题发生(鉴于问题的性质仍在等待),但从现在发出的请求中看到了一些有趣且意外的响应。如果我们能对这里发生的事情进行一些澄清,那就太好了。我不相信我们期望删除
crossorigin="anonymous"
有这样的效果,甚至理解为什么它之前如此 splinter ,因为我们的服务器设置为发送正确的 header 和
Vary
标题。
curl -I 'https://s3.amazonaws.com/olympus.lystable.com/style.allapps.5ebcc4d28ec238a53f46d6c8e12900d1.css' -H 'Pragma: no-cache' -H 'Accept-Encoding: gzip, deflate, br' -H 'Accept-Language: en-GB,en-US;q=0.8,en;q=0.6' -H 'User-Agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Ubuntu Chromium/59.0.3071.109 Chrome/59.0.3071.109 Safari/537.36' -H 'Accept: text/css,*/*;q=0.1' -H 'Referer: https://asos.kalohq.com/categories' -H 'Connection: keep-alive' -H 'DPR: 1' -H 'Cache-Control: no-cache' -H "Origin: https://kalohq.com" --compressed
HTTP/1.1 200 OK
x-amz-id-2: kxOvBrYsKyZ42wGgJu8iyRZ8q6j5DHDC6QoK1xn2e8FO1wIEEVkxQ0JvGQTmwrN/Njf8EOlmLrE=
x-amz-request-id: DA8B5488D3A7EF73
Date: Thu, 13 Jul 2017 13:27:47 GMT
Last-Modified: Thu, 13 Jul 2017 11:30:50 GMT
ETag: "c765a0a215cb4c9a074f22c3863c1223"
Cache-Control: max-age=31556926
Content-Encoding: gzip
Accept-Ranges: bytes
Content-Type: text/css
Content-Length: 5887
Server: AmazonS3
curl -H "Origin: https://kalohq.com" -I https://assets-frontend.kalohq.com/style.allapps.5ebcc4d28ec238a53f46d6c8e12900d1.css
HTTP/1.1 200 OK
Content-Type: text/css
Content-Length: 5887
Connection: keep-alive
Date: Thu, 13 Jul 2017 13:33:09 GMT
Access-Control-Allow-Origin: *
Access-Control-Allow-Methods: GET
Access-Control-Max-Age: -1
Last-Modified: Thu, 13 Jul 2017 11:30:50 GMT
ETag: "c765a0a215cb4c9a074f22c3863c1223"
Cache-Control: max-age=31556926
Content-Encoding: gzip
Accept-Ranges: bytes
Server: AmazonS3
Vary: Origin,Access-Control-Request-Headers,Access-Control-Request-Method
Age: 69
X-Cache: Hit from cloudfront
Via: 1.1 a19c66da9b402e0bee3fd29619661850.cloudfront.net (CloudFront)
X-Amz-Cf-Id: 3wQ7Z6EaAcMscGirwsYVi1M_rvoc1fbI034QY4QZd6IqmlRzLRllEg==
crossorigin="anonymous"
标签解决了这个问题。因为我们之前在脚本标签上有这个属性,所以正在调查为什么这突然开始成为这个版本的问题。
最佳答案
https://assets-frontend.kalohq.ink/style.allapps.add899080acbbeed5bb6a7301d234b65.css仅当存在“Origin” header 时才返回 CORS header (与 CORS 请求一起发送,但不是常规请求)。
这是发生的事情:
<link rel="stylesheet">
)。此缓存由于 Cache-Control
标题。 Access-Control-Allow-Origin
标题。 Vary
header 指示其响应根据
Origin
而变化 header (和其他)。它发送这个头来响应 CORS 请求,但它也应该发送它来响应非 CORS 请求。
fetch()
发送的请求)不应该与缓存中的项目匹配要求提供凭据。我认为这里还有其他浏览器的行为类似于 Chrome,但 Firefox 没有。
Vary
header 是正确的修复。
Vary: Origin, Access-Control-Request-Headers, Access-Control-Request-Method
关于browser - 缓存对 CORS : No 'Access-Control-Allow-Origin' header is present on the requested resource 的影响,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/44800431/
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