mirror of
https://github.com/GNS3/gns3-server.git
synced 2025-01-18 23:43:48 +02:00
119 lines
3.6 KiB
Python
119 lines
3.6 KiB
Python
#!/usr/bin/env python
|
||
#
|
||
# Copyright (C) 2016 GNS3 Technologies Inc.
|
||
#
|
||
# This program is free software: you can redistribute it and/or modify
|
||
# it under the terms of the GNU General Public License as published by
|
||
# the Free Software Foundation, either version 3 of the License, or
|
||
# (at your option) any later version.
|
||
#
|
||
# This program is distributed in the hope that it will be useful,
|
||
# but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||
# GNU General Public License for more details.
|
||
#
|
||
# You should have received a copy of the GNU General Public License
|
||
# along with this program. If not, see <http://www.gnu.org/licenses/>.
|
||
|
||
import asyncio
|
||
import psutil
|
||
import json
|
||
from contextlib import contextmanager
|
||
|
||
|
||
class NotificationQueue(asyncio.Queue):
|
||
"""
|
||
Queue returned by the notification manager.
|
||
"""
|
||
def __init__(self):
|
||
super().__init__()
|
||
self._first = True
|
||
|
||
@asyncio.coroutine
|
||
def get(self, timeout):
|
||
"""
|
||
When timeout is expire we send a ping notification with server informations
|
||
"""
|
||
|
||
# At first get we return a ping so the client receive immediately data
|
||
if self._first:
|
||
self._first = False
|
||
return ("ping", self._getPing(), {})
|
||
|
||
try:
|
||
(action, msg, kwargs) = yield from asyncio.wait_for(super().get(), timeout)
|
||
except asyncio.futures.TimeoutError:
|
||
return ("ping", self._getPing(), {})
|
||
return (action, msg, kwargs)
|
||
|
||
def _getPing(self):
|
||
"""
|
||
Return the content of the ping notification
|
||
"""
|
||
msg = {}
|
||
# Non blocking call in order to get cpu usage. First call will return 0
|
||
msg["cpu_usage_percent"] = psutil.cpu_percent(interval=None)
|
||
msg["memory_usage_percent"] = psutil.virtual_memory().percent
|
||
return msg
|
||
|
||
@asyncio.coroutine
|
||
def get_json(self, timeout):
|
||
"""
|
||
Get a message as a JSON
|
||
"""
|
||
(action, msg, kwargs) = yield from self.get(timeout)
|
||
if hasattr(msg, "__json__"):
|
||
msg = {"action": action, "event": msg.__json__()}
|
||
else:
|
||
msg = {"action": action, "event": msg}
|
||
msg.update(kwargs)
|
||
return json.dumps(msg, sort_keys=True)
|
||
|
||
|
||
class NotificationManager:
|
||
"""
|
||
Manage the notification queue where the controller
|
||
will connect to get notifications from hypervisors
|
||
"""
|
||
|
||
def __init__(self):
|
||
self._listeners = set()
|
||
|
||
@contextmanager
|
||
def queue(self):
|
||
"""
|
||
Get a queue of notifications
|
||
|
||
Use it with Python with
|
||
"""
|
||
queue = NotificationQueue()
|
||
self._listeners.add(queue)
|
||
yield queue
|
||
self._listeners.remove(queue)
|
||
|
||
def emit(self, action, event, **kwargs):
|
||
"""
|
||
Send an event to all the client listening for notifications
|
||
|
||
:param action: Action name
|
||
:param event: Event to send
|
||
:param kwargs: Add this meta to the notif (project_id for example)
|
||
"""
|
||
for listener in self._listeners:
|
||
listener.put_nowait((action, event, kwargs))
|
||
|
||
@staticmethod
|
||
def reset():
|
||
NotificationManager._instance = None
|
||
|
||
@staticmethod
|
||
def instance():
|
||
"""
|
||
Singleton to return only on instance of NotificationManager.
|
||
:returns: instance of NotificationManager
|
||
"""
|
||
|
||
if not hasattr(NotificationManager, '_instance') or NotificationManager._instance is None:
|
||
NotificationManager._instance = NotificationManager()
|
||
return NotificationManager._instance
|