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- Committer: Jason Conti
- Date: 2010-02-20 13:55:51 UTC
- Revision ID: jason.conti@gmail.com-20100220135551-lwjf8ef1vdoccr91
Moved LogWatcher and Notifications out of the main project because they are no longer needed.
- files removed:
- LogWatcher.py
added
removed
Notifications.py
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"""
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Notifications.py
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by Jason Conti
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February 15, 2010
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Reads notifications in the notify-osd.log format specified at:
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https://wiki.ubuntu.com/NotifyOSD#Logging notifications
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"""
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import re
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import time
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from LogWatcher import LogWatcher
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message_header = re.compile("""
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^
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\[ # [timestamp, process-name, status?]
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(
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\d{4}-\d{2}-\d{2} # date YYYY-mm-dd
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[Tt]
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\d{2}:\d{2}:\d{2} # time HH-MM-SS
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([Zz]|[+-]\d{2}:\d{2}) # time offset
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)
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,
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([^,\]]+) # process name
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(,([^\]]+))? # optional status
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\]
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(.*) # title
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$
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""", re.VERBOSE)
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class Message(object):
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"""A notification message"""
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def __init__(self, timestamp, process_name, status, title):
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self.timestamp = timestamp
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self.process_name = process_name
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self.status = status
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self.title = title
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self.body = ""
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def append_body(self, body):
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"""Appends a body line to the message."""
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self.body += body
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def formatted_time(self):
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"""Returned the time in a different format."""
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t = time.strptime(self.timestamp.upper(), "%Y-%m-%dT%H:%M:%S-00:00")
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return time.strftime("%B %d, %Y at %I:%M:%S %p", t)
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class Notifications(object):
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"""Reads notifications from a log file and sends them to the listeners."""
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def __init__(self, path):
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self._path = path
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self._listeners = set()
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def add_listener(self, f):
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"""A listener is a function of a single argument, the messages
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received."""
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self._listeners.add(f)
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def remove_listener(self, f):
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"""Removes f from the set of listeners."""
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self._listeners.remove(f)
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def start(self):
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"""Reads the previous messages, sends them to the listeners and starts
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watching for more messages."""
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# Get the previous messages
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f = open(self._path, "r")
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messages = f.read()
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f.close()
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self._message_received(None, messages)
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self._watcher = LogWatcher(self._path)
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self._watcher.connect("changed", self._message_received)
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self._watcher.start()
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def stop(self):
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"""Stops watching for more messages."""
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self._watcher.stop()
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def _notify_listeners(self, messages):
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"""Notifies the listeners of new messages."""
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for f in self._listeners:
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f(messages)
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def _message_received(self, watcher, messages):
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"""Callback that parses messages and adds them to the queue."""
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queue = self._parse_messages(messages)
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if len(queue) > 0:
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self._notify_listeners(queue)
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def _parse_messages(self, messages):
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"""Returns a list of parsed messages."""
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lines = messages.splitlines()
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queue = []
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message = None
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for line in lines:
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# Try to parse a new message, discard the line if the header
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# doesn't match
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if message == None:
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m = message_header.match(line)
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if m != None:
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header = m.groups()
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timestamp = header[0].strip()
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process_name = header[2].strip()
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status = header[4]
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# Status may not exist
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if status == None:
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status = ""
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else:
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status = status.strip()
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title = header[5].strip()
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message = Message(timestamp, process_name, status, title)
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# Messages are delimited by a blank line
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else:
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if line.strip() == "":
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queue.append(message)
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message = None
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else:
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message.append_body(line)
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# Don't forget the last message (should probably never happen)
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if message != None:
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queue.append(message)
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return queue
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Loggerhead is a web-based interface for Breezy
Version: 2.0.1