--append

glances/core/glances_autodiscover.py

@@ -0,0 +1,149 @@
+# -*- coding: utf-8 -*-
+#
+# This file is part of Glances.
+#
+# Copyright (C) 2014 Nicolargo <nicolas@nicolargo.com>
+#
+# Glances is free software; you can redistribute it and/or modify
+# it under the terms of the GNU Lesser General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# Glances 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 Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public License
+# along with this program. If not, see <http://www.gnu.org/licenses/>.
+
+"""Manage autodiscover Glances server (thk to the ZeroConf protocol)."""
+
+# Import system libs
+import socket
+try:
+    from zeroconf import ServiceBrowser, ServiceInfo, Zeroconf
+    zeroconf_tag = True
+except ImportError:
+    zeroconf_tag = False
+
+# Import Glances libs
+from glances.core.glances_globals import appname, version, logger
+
+# Global var
+zeroconf_type = "_%s._tcp." % appname
+
+
+class AutoDiscovered(object):
+    """Class to manage the auto discovered servers dict"""
+
+    def __init__(self):
+        # server_dict is a dict of dict
+        # key: ip:port
+        # value: {'cpu': 3, 'mem': 34 ...}
+        self._server_dict = {}
+
+    def get_servers_list(self):
+        """Return the current server list (dict of dict)"""
+        return self._server_dict
+
+    def add_server(self, name, ip, port):
+        """Add a new server to the dict"""
+        self._server_dict[name] = {'ip': ip, 'port': port}
+        logger.debug("Servers list: %s" % self._server_dict)
+
+    def remove_server(self, name):
+        """Remove a server from the dict"""
+        del(self._server_dict[name])
+        logger.debug("Servers list: %s" % self._server_dict)
+
+
+class GlancesAutoDiscoverListener(object):
+    """Zeroconf listener for Glances server"""
+
+    def __init__(self):
+        # Create an instance of the servers list
+        self.servers = AutoDiscovered()
+
+    def get_servers_list(self):
+        """Return the current server list (dict of dict)"""
+        return self.servers.get_servers_list()
+
+    def addService(self, zeroconf, srv_type, srv_name):
+        """Method called when a new Zeroconf client is detected
+        Return True if the zeroconf client is a Glances server
+        Note: the return code will never be used
+        """
+        if srv_type != zeroconf_type:
+            return False
+        info = zeroconf.getServiceInfo(srv_type, srv_name)
+        if info:
+            new_server_ip = socket.inet_ntoa(info.getAddress())
+            new_server_port = info.getPort()
+
+            # !!! Only for dev
+            # new_server_name = info.getServer()
+            prop = info.getProperties()
+            if prop:
+                logger.debug("Zeroconf properties are %s" % prop)
+
+            # Add server to the global dict
+            self.servers.add_server(srv_name, new_server_ip, new_server_port)
+            logger.info("New Glances server detected (%s from %s:%s)" % (srv_name, new_server_ip, new_server_port))
+        else:
+            logger.warning("New Glances server detected, but Zeroconf info failed to be grabbed")
+        return True
+
+    def removeService(self, zeroconf, srv_type, srv_name):
+        # Remove the server from the list
+        self.servers.remove_server(srv_name)
+        logger.info("Glances server %s removed from the autodetect list" % srv_name)
+
+
+class GlancesAutoDiscoverServer(object):
+    """Implementation of the Zeroconf protocol (server side for the Glances client)"""
+
+    def __init__(self, args=None):
+        if zeroconf_tag:
+            logger.info("Init autodiscover mode (Zeroconf protocol)")
+            self.zeroconf = Zeroconf()
+            self.listener = GlancesAutoDiscoverListener()
+            self.browser = ServiceBrowser(self.zeroconf, zeroconf_type, self.listener)
+        else:
+            logger.error("Can not start autodiscover mode (Zeroconf lib is not installed)")
+
+    def get_servers_list(self):
+        """Return the current server list (dict of dict)"""
+        if zeroconf_tag:
+            return self.listener.get_servers_list()
+        else:
+            return {}
+
+    def close(self):
+        if zeroconf_tag:
+            self.zeroconf.close()
+
+
+class GlancesAutoDiscoverClient(object):
+    """Implementation of the Zeroconf protocol (client side for the Glances server)"""
+
+    def __init__(self, hostname, args=None):
+        if zeroconf_tag:
+            logger.info("Announce the Glances server on the local area network")
+            self.zeroconf = Zeroconf()
+            self.info = ServiceInfo(zeroconf_type,
+                                    hostname + '.' + zeroconf_type,
+                                    address=socket.inet_aton(args.bind_address),
+                                    port=args.port,
+                                    weight=0,
+                                    priority=0,
+                                    properties={},
+                                    server=hostname)
+            self.zeroconf.registerService(self.info)
+        else:
+            logger.error("Can not announce Glances server on the network (Zeroconf lib is not installed)")
+
+    def close(self):
+        if zeroconf_tag:
+            self.zeroconf.unregisterService(self.info)
+            self.zeroconf.close()