To get some logging of requests we had to add the following to proxy-swift.conf manually:
[app:proxy-server]
[...]
set log_name = swift-proxy-server
set log_facility = LOG_LOCAL0
set log_level = DEBUG
set access_log_name = swift-proxy-server
set access_log_facility = LOG_LOCAL0
set access_log_level = DEBUG
set log_headers = True
[filter:proxy-logging]
use = egg:swift#proxy_logging
The charm should support logging via a config option. Also, per http://docs.openstack.org/developer/swift/deployment_guide.html#logging-considerations "Swift is set up to log directly to syslog. Every service can be configured with the log_facility option to set the syslog log facility destination. We recommended using syslog-ng to route the logs to specific log files locally on the server and also to remote log collecting servers". Custom logfiles would be highly preferrable.