id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc	uname	nginx_version
761	The auth_request does not supports query string/arguments	rustler2000.livejournal.com		"Having in config:
{{{
auth_request /users/v1/auth?usergroup=devel;
}}}
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The debug log from nginx shows:
{{{
2013/01/01 01:52:49 [notice] 1607#0: *125 ""^/users/(.*)"" matches ""/users/v1/auth?usergroup=devel"", client: 10.9.96.2, server: localhost, request: ""GET /runner/v1/status HTTP/1.1"", subrequest: ""/users/v1/auth?usergroup=devel"", host: ""10.9.96.81""
2013/01/01 01:52:49 [notice] 1607#0: *125 rewritten data: ""/v1/auth?usergroup=devel"", args: """", client: 10.9.96.2, server: localhost, request: ""GET /runner/v1/status HTTP/1.1"", subrequest: ""/users/v1/auth?usergroup=devel"", host: ""10.9.96.81""
}}}

The strace on upstream shows:
{{{
recv(6, ""GET /v1/auth%3Fusergroup=devel H""..., 8192, 0) = 507
}}}
[[BR]]

As it seen - the question mark separating path and query got urlencoded and whole query string became part of path. 

Checking the code of auth_request seems that subrequest made w/o taking care of args - there is NULL passed.
"	enhancement	new	minor		nginx-module			auth,auth_request			"nginx version: nginx/1.8.0 (i686-pc-linux-gnu)
built by gcc 4.6.2
..."