# coding=utf-8
from circuits import Event, Timer
from isomer.component import ConfigurableComponent, handler
from isomer.events.client import send # , clientdisconnect
from isomer.events.system import authorized_event
from isomer.logger import error, debug, get_logfile
[docs]class history(authorized_event):
pass
[docs]class subscribe(authorized_event):
pass
[docs]class Syslog(ConfigurableComponent):
"""
System log access component
Handles all the frontend log history requests.
"""
[docs] def __init__(self, *args):
super(Syslog, self).__init__("SYSLOG", *args)
self.log("Started")
self.subscribers = []
self.log_file = open(get_logfile())
self.log_position = 0
self.follow_timer = Timer(1, Event.create("syslog_follow"), persist=True)
[docs] @handler(subscribe)
def subscribe(self, event):
self.subscribers.append(event.client.uuid)
[docs] @handler("clientdisconnect", priority=1000)
def disconnect(self, event):
self.log("Disconnected: ", event.clientuuid, lvl=debug)
if event.clientuuid in self.subscribers:
self.subscribers.remove(event.clientuuid)
def _logupdate(self, new_messages):
packet = {
"component": "isomer.ui.syslog",
"action": "update",
"data": new_messages,
}
for subscriber in self.subscribers:
self.fireEvent(send(subscriber, packet, fail_quiet=True))
[docs] @handler("syslog_follow")
def follow(self):
where = self.log_file.tell()
line = self.log_file.readline()
if not line:
self.log_file.seek(where)
else:
self._logupdate(line)
[docs] @handler(history)
def history(self, event):
try:
limit = event.data["limit"]
end = event.data["end"]
except (KeyError, AttributeError) as e:
self.log("Error during event lookup:", e, type(e), exc=True, lvl=error)
return
self.log("History requested:", limit, end, lvl=debug)
messages = []
history_packet = {
"component": "isomer.ui.syslog",
"action": "history",
"data": {"limit": limit, "end": end, "history": messages},
}
self.fireEvent(send(event.client.uuid, history_packet))