class ZMQPushLogHandler(logging.Handler):
"""
Sends logging to ZMQ PUSH socket(s).
Log messages have two parts (ZMQ multipart messages): a header and a body.
The header is a JSON object with metadata describing the log event.
The body is the content of the log message.
"""
def __init__(self, log_path, zmq_context=None, level=logging.NOTSET):
"""
log_path
The filename that the program would log to if it were using normal
file based logging.
This may include slashes to indicate directories.
Used as a key to identify this log.
zmq_context
zeromq context. A program should have only one zmq context.
If you don't pass a context in, we will create one.
level
minimum log level. This is usually set externally
"""
super(ZMQPushLogHandler, self).__init__(level)
# if the caller does not suppy a zeromq context (they really should)
# we create our own and hold a reference to it so we can terminate it.
if zmq_context is None:
self._zmq_context = zmq.Context()
zmq_context = self._zmq_context
else:
self._zmq_context = None
self._log_line_pusher = LogLinePusher(zmq_context, log_path)
def emit(self, record):
"""
Do whatever it takes to actually log the specified logging record.
record
python LogRecord object
we use only the string returned by record.getMessage()
"""
formatted_record = self.format(record)
self._log_line_pusher.push_log_line(formatted_record)
def close(self):
"""
Tidy up any resources used by the handler.
"""
super(ZMQPushLogHandler, self).close()
self._log_line_pusher.close()
if self._zmq_context is not None:
self._zmq_context.term()
def __init__(self, log_path, zmq_context=None, level=logging.NOTSET):
"""
log_path
The filename that the program would log to if it were using normal
file based logging.
This may include slashes to indicate directories.
Used as a key to identify this log.
zmq_context
zeromq context. A program should have only one zmq context.
If you don't pass a context in, we will create one.
level
minimum log level. This is usually set externally
"""
super(ZMQPushLogHandler, self).__init__(level)
# if the caller does not suppy a zeromq context (they really should)
# we create our own and hold a reference to it so we can terminate it.
if zmq_context is None:
self._zmq_context = zmq.Context()
zmq_context = self._zmq_context
else:
self._zmq_context = None
self._log_line_pusher = LogLinePusher(zmq_context, log_path)
def main():
"""
main entry point
"""
args = _parse_commandline()
zmq_context = zmq.Context()
log_line_pusher = LogLinePusher(zmq_context, args.log_path)
halt_event = set_signal_handler()
while not halt_event.is_set():
try:
line = sys.stdin.readline()
except IOError:
instance = sys.exc_info()[1]
if instance.errno == errno.EINTR and halt_event.is_set():
break
raise
log_line_pusher.push_log_line(line[:-1])
log_line_pusher.close()
zmq_context.term()
return 0
