id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc	uname	nginx_version
736	Nginx responses 412 to invalid If-Unmodified-Since request-header	wai wai li		"Sending request with If-Unmodified-Since header to Ngnix:

1. If the specified date is valid, Nginx responses 200
{{{
   > If-Unmodified-Since: Wed, 25 Mar 2015 02:07:01 GMT
   >
   < HTTP/1.1 200 OK
   * Server nginx/1.7.7 is not blacklisted
   < Server: nginx/1.7.7
   < Date: Wed, 25 Mar 2015 02:07:55 GMT
}}}

2. If the specified date is invalid, Nginx responses 412
{{{
   > If-Unmodified-Since: Wed, 25 MMar 2015 02:07:01 GMT
   >
   < HTTP/1.1 412 Precondition Failed
   * Server nginx/1.7.7 is not blacklisted
   < Server: nginx/1.7.7
   < Date: Wed, 25 Mar 2015 02:11:24 GMT
   < Content-Type: text/html
   < Content-Length: 188
   < Connection: keep-alive
}}}

{{{
   > If-Unmodified-Since: Wed, 25 Mar 2015 02,07,01 GMT
   >
   < HTTP/1.1 412 Precondition Failed
   * Server nginx/1.7.7 is not blacklisted
   < Server: nginx/1.7.7
   < Date: Wed, 25 Mar 2015 02:12:23 GMT
   < Content-Type: text/html
   < Content-Length: 188
   < Connection: keep-alive
}}}

According to [http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.28]
""
If the specified date is invalid, the header is ignored.
""

In this case, should Nginx responses 200?"	defect	closed	major		nginx-module	1.7.x	wontfix	invalid If-Unmodified-Since		N/A	nginx/1.7.7