Access-Control-Max-Age 这个响应首部表示 preflight request (预检请求)的返回结果(即 Access-Control-Allow-Methods 和Access-Control-Allow-Headers...用法: Access-Control-Max-Age: 返回结果可以用于缓存的最长时间,单位是秒。...注:需要注意的是Access-Control-Max-Age的设置针对完全一样的url,如果url加上路径参数,其中一个url的Access-Control-Max-Age设置对另一个url没有效果!!
,在POST请求发出之前一般会发送pre-flight请求来试探下服务器,看下是否有些请求头或者请求方法服务器端是否支持,如下图所示: 从上图可以看出服务器端支持POST、GET等请求,上面返回的 Access-Control-Max-Age
/允许的访问方法, 代表全部可以访问 httpServletResponse.setHeader("Access-Control-Allow-Methods", "POST, GET"); //Access-Control-Max-Age...用于 CORS 相关配置的缓存 httpServletResponse.setHeader("Access-Control-Max-Age", "3600"); httpServletResponse.setHeader
token,r,sign,time"; add_header 'Access-Control-Expose-Headers' 'Content-Disposition'; add_header 'Access-Control-Max-Age...Access-Control-Allow-Credentials' 'true'; #add_header 'Access-Control-Allow-Methods' 'GET, POST, OPTIONS'; #add_header 'Access-Control-Max-Age...proxy_set_header Host $host; } } 提及个优化的事,就是为了快速访问网页,提升访问效率,有很多解决方式,比如服务端加缓存,前端懒加载等,但是忽略了一个很容易的优化,那就是Access-Control-Max-Age
Access-Control-Allow-Origin 允许跨域请求的域名,如果要允许所有域名则设置为 * Access-Control-Allow-Headers 将实际请求所携带的首部字段告诉服务器 Access-Control-Max-Age...转为简单请求,如用 JSONP 做跨域请求 对 options 请求进行缓存,服务器端设置 Access-Control-Max-Age 字段,那么当第一次请求该 URL 时会发出 OPTIONS 请求...,浏览器会根据返回的 Access-Control-Max-Age 字段缓存该请求的 OPTIONS 预检请求的响应结果(具体缓存时间还取决于浏览器的支持的默认最大值,取两者最小值,一般为 10 分钟)...(chrome 打开控制台可以看到,当服务器响应 Access-Control-Max-Age 时只有第一次请求会有预检,后面不会了。注意要开启缓存,去掉 disable cache 勾选。)
整理代码如下,添加在 location 节点 add_header 'Access-Control-Allow-Origin' '*'; add_header 'Access-Control-Max-Age...add_header 'Access-Control-Allow-Origin' '*' always; add_header 'Access-Control-Max-Age' '1000' always...Header always set Access-Control-Allow-Methods "POST, GET, OPTIONS, DELETE, PUT" Header always set Access-Control-Max-Age
标识该资源支持哪些方法,例如:POST, GET, PUT, DELETE Access-Control-Allow-Headers: 标识允许哪些额外的自定义 header 字段和非简单值的字段 Access-Control-Max-Age...服务器端设置Access-Control-Max-Age字段 当第一次请求该URL时会发出OPTIONS请求,浏览器会根据返回的Access-Control-Max-Age字段缓存该OPTIONS预检请求的响应结果...(chrome 打开控制台可以看到,当服务器响应Access-Control-Max-Age时只有第一次请求会有预检,后面不会了。...TimeSpan.FromHours(24)); }); }); } - https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Access-Control-Max-Age
相关信息就一切OK了: Access-Control-Allow-Origin: "*" Access-Control-Allow-Methods: "GET" Access-Control-Max-Age...Apache/2.0.61 (Unix) Access-Control-Allow-Origin: * Access-Control-Allow-Methods: GET Access-Control-Max-Age...注意这一过程是浏览器自动实现的,这一点是不是非常棒.一些header信息的设置如下: Access-Control-Allow-Origin:| * // 授权的源控制 Access-Control-Max-Age
允许跨域请求的域) access-control-allow-methods(允许跨域请求的请求方式) access-control-allow-headers(允许跨域请求的请求头) 另外,服务端还可以通过Access-Control-Max-Age...如果上面的中有一条我们没法避免就只能设置认证的生效时间了Access-Control-Max-Age。...Access-Control-Allow-Headers' '*'; add_header 'Access-Control-Allow-Credentials' 'true' always; add_header 'Access-Control-Max-Age...' 36000; if ($request_method = OPTIONS ) { return 200; } } 其中: Access-Control-Max-Age,用来指定本次预检请求的有效期
response.setHeader("Access-Control-Allow-Methods", "*"); response.setHeader("Access-Control-Max-Age...response.setHeader("Access-Control-Allow-Credentials", "true"); response.setHeader("Access-Control-Max-Age
Access-Control-Allow-Origin: *");//当前跨域域名 * 全部 header("Access-Control-Allow-Methods: GET,POST,PUT,DELETE");// 响应类型 header("Access-Control-Max-Age...: 3628800");//Access-Control-Max-Age用来指定本次预检请求的有效期,单位为秒,,在此期间不用发出另一条预检请求。
允许的访问方法 rep.setHeader("Access-Control-Allow-Methods","POST, GET, PUT, OPTIONS, DELETE, PATCH"); // Access-Control-Max-Age...用于 CORS 相关配置的缓存 rep.setHeader("Access-Control-Max-Age", "3600"); rep.setHeader("Access-Control-Allow-Headers
Access-Control-Allow-Origin: http://kbiao.me Access-Control-Max-Age: 3628800 Access-Control-Allow-methods...Access-Control-Allow-Credentail: true “Access-Control-Allow-Origin"表明它允许” http://kbiao.me "发起跨域请求 "Access-Control-Max-Age
Access-Control-Allow-Headers "Origin, X-Requested-With, Content-Type, Accept, token" Header set Access-Control-Max-Age...Access-Control-Allow-Headers "Origin, X-Requested-With, Content-Type, Accept, token" Header set Access-Control-Max-Age
DELETE < Access-Control-Allow-Origin: https://cos.com < Access-Control-Expose-Headers: X-myHeader < Access-Control-Max-Age...DELETE < Access-Control-Allow-Origin: https://cos.com < Access-Control-Expose-Headers: X-myHeader < Access-Control-Max-Age...DELETE < Access-Control-Allow-Origin: https://cos.com < Access-Control-Expose-Headers: X-myHeader < Access-Control-Max-Age...PUT,GET,POST,DELETE < Access-Control-Allow-Headers: < Access-Control-Expose-Headers: X-myHeader < Access-Control-Max-Age...DELETE < Access-Control-Allow-Origin: https://cos.com < Access-Control-Expose-Headers: X-myHeader < Access-Control-Max-Age
协议更详细内容参考跨域资源共享 CORS 详解 CROS常见header CORS具有以下常见的header Access-Control-Allow-Origin: http://kbiao.me Access-Control-Max-Age...Access-Control-Allow-Headers: content-type "Access-Control-Allow-Origin"表明它允许" http://kbiao.me "发起跨域请求 "Access-Control-Max-Age...response.setHeader("Access-Control-Allow-Methods", "POST, GET, OPTIONS, DELETE"); response.setHeader("Access-Control-Max-Age...","*"); response.addHeader("Access-Control-Allow-Methods","*"); response.addHeader("Access-Control-Max-Age...response.addHeader("Access-Control-Allow-Headers", "Content-Type"); response.addHeader("Access-Control-Max-Age
access-control-allow-methods", "access-control-allow-origin", "access-control-max-age...access-control-allow-methods", "access-control-allow-origin", "access-control-max-age
response.setHeader("Access-Control-Allow-Methods", "POST, GET, PATCH, DELETE, PUT"); response.setHeader("Access-Control-Max-Age...Access-Control-Max-Age 该字段可选,用来指定本次预检请求的有效期,单位为秒。在有效期间,不用发出另一条预检请求。...顺便提一下,如果在开发中,发现每次发起请求都是两条,一次OPTIONS,一次正常请求,注意是每次,那么就需要配置Access-Control-Max-Age,避免每次都发出预检请求。
解决方法 一种比较合适的解决方法就是增加响应头“Access-Control-Max-Age”来控制浏览器在多长时间内(单位为秒)无需在请求时发送预检请求,从而减少不必要的预检请求。...process_request(self, request): pass def process_response(self, request, response): response['Access-Control-Max-Age
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