Move endpoints to routes & preparations to use a database.

gns3server/utils/notification_queue.py

@@ -0,0 +1,80 @@
+#!/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 json
+import psutil
+
+from gns3server.utils.cpu_percent import CpuPercent
+from gns3server.utils.path import get_default_project_directory
+
+import logging
+log = logging.getLogger(__name__)
+
+
+class NotificationQueue(asyncio.Queue):
+    """
+    Queue returned by the notification manager.
+    """
+
+    def __init__(self):
+        super().__init__()
+        self._first = True
+
+    async def get(self, timeout):
+        """
+        When timeout is expire we send a ping notification with server information
+        """
+
+        # At first get we return a ping so the client immediately receives data
+        if self._first:
+            self._first = False
+            return ("ping", self._getPing(), {})
+
+        try:
+            (action, msg, kwargs) = await asyncio.wait_for(super().get(), timeout)
+        except asyncio.TimeoutError:
+            return ("ping", self._getPing(), {})
+        return (action, msg, kwargs)
+
+    def _getPing(self):
+        """
+        Return the content of the ping notification
+        """
+        msg = {"cpu_usage_percent": 0,
+               "memory_usage_percent": 0,
+               "disk_usage_percent": 0}
+        # Non blocking call in order to get cpu usage. First call will return 0
+        try:
+            msg["cpu_usage_percent"] = CpuPercent.get(interval=None)
+            msg["memory_usage_percent"] = psutil.virtual_memory().percent
+            msg["disk_usage_percent"] = psutil.disk_usage(get_default_project_directory()).percent
+        except OSError as e:
+            log.warning("Could not get CPU and memory usage from psutil: {}".format(e))
+        return msg
+
+    async def get_json(self, timeout):
+        """
+        Get a message as a JSON
+        """
+        (action, msg, kwargs) = await 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)