Logging

Hypercorn has two loggers, an access logger and an error logger. By default neither will actively log. The special value of - can be used as the logging target in order to log to stdout and stderr respectively. Any other value is considered a filepath to target.

Configuring access logs

The access log format can be configured by specifying the atoms (see below) to include in a specific format. By default hypercorn will choose %(h)s %(S)s %(r)s %(s)s %(b)s %(D)s as the format. The configuration variable access_log_format specifies the format used.

Access log atoms

The following atoms, a superset of those in Gunicorn, are available for use.

Identifier	Description
h	remote address
l	'-'
u	user name
t	date of the request
r	status line (e.g. GET / h11)
m	request method
U	URL path without query string
q	query string
H	protocol
s	status
S	scheme {http, https, ws, wss}
B	response length
b	response length or '-' (CLF format)
f	referer
a	user agent
T	request time in seconds
D	request time in microseconds
L	request time in decimal seconds
p	process ID
{Header}i	request header
{Header}o	response header
{Variable}e	environment variable

Customising the access logger

The acces logger class can be customised by changing the access_logger_class attribute of the Config class. This is only possible when using the python based configuration file. The hypercorn.logging.AccessLogger class is used by default.