Variable	Value
$aliased_uri	The part of $uri left over after removing what matches $location.
$bytes_sent	Same as access_log's $bytes_sent.
$cache_age	Age of the cache file used to satisfy requests in seconds.
$cache_file	The cache file path for a cached response.
$cache_key	The cache key hash for a cached response.
$connection	Same as access_log's $connection.
$connection_requests	Number of requests handled by the current connection.
$ext	The extension from $uri.
$location	Set to the name of the current location block.
$msec	Same as access_log's $msec.
$original_uri	The original parsed uri.
$pipe	Same as access_log's $pipe.
$process_slot	Slot in nginx's child process list.
$random	Random integer.
$redirect_count	The number of times the current request has been internally redirected.
$request_length	Same as access_log's $request_length.
$request_received	Timestamp when the request was received, to msec precision.
$request_time	Same as access_log's $request_time.
$request_version	HTTP version used by the request.
$sorted_args	All of the query string args, sorted alphabetically.
$status	Same as access_log's $status.
$stub_stat_accepted	Same as the "accepts" field of the stub_status module output.
$stub_stat_active	Same as the "active connections" field of the stub_status module output.
$stub_stat_handled	Same as the "handled" field of the stub_status module output.
$stub_stat_reading	Same as the "reading" field of the stub_status module output.
$stub_stat_requests	Same as the "requests" field of the stub_status module output.
$stub_stat_waiting	Same as the "waiting" field of the stub_status module output.
$stub_stat_writing	Same as the "writing" field of the stub_status module output.
$subrequest_count	The number of subrequests performed for this request.
$time_iso8601	Same as access_log's $time_iso8601.
$time_local	Same as access_log's $time_local.
$wsgi_path_info	The part of $uri that matches $location, stripped of any trailing /.
$wsgi_script_name	The part of $uri that isn't contained in $wsgi_path_info.