
HTTP 常见请求头

Request
- 
accept
- accept-encoding
 - accept-language
 - content-type
 - cookie
 - origin
 - referer
 - user-agent
 - if-modified-since
 - cache-control
 
Response
- content-type
 - Content-Length
 - content-encoding
 - access-control-allow-credentials
 - access-control-allow-origin
 - Access-Control-Expose-Headers
 - Access-Control-Max-Age
 - date
 - cache-control
 - last-modified
 - ETag