src/dss/server/dss_server.py

   1 # Copyright 2019 Nokia
   2 #
   3 # Licensed under the Apache License, Version 2.0 (the "License");
   4 # you may not use this file except in compliance with the License.
   5 # You may obtain a copy of the License at
   6 #
   7 #     http://www.apache.org/licenses/LICENSE-2.0
   8 #
   9 # Unless required by applicable law or agreed to in writing, software
  10 # distributed under the License is distributed on an "AS IS" BASIS,
  11 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12 # See the License for the specific language governing permissions and
  13 # limitations under the License.
  14 #
  15
  16 import socket
  17 import logging
  18 import select
  19 import errno
  20 import os
  21
  22 from dss.server import dss_connection
  23 from dss.server import dss_config
  24 from dss.server import dss_rpc_processor
  25
  26 class Server(object):
  27     def __init__(self, conf, rpc_processor):
  28         self.uds = conf.get_listening_uds()
  29         self.rpc_processor = rpc_processor
  30         self.transport_type = conf.get_transport_type()
  31         self.stopped = False
  32         if (self.transport_type == 'stream'):
  33             self.server = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
  34         else:
  35             self.server = socket.socket(socket.AF_UNIX, socket.SOCK_DGRAM)
  36         self.server.setblocking(0)
  37         self.remove_uds()
  38
  39     def start(self):
  40         logging.info("Server listening at %s" % self.uds)
  41         self.server.bind(self.uds)
  42         if self.transport_type == 'stream':
  43             self.server.listen(1)
  44         inputs = [self.server]
  45         while not self.stopped:
  46             try:
  47                 readable, writable, errored = select.select(inputs, [], [])
  48                 for s in readable:
  49                     if s is self.server:
  50                         if self.transport_type == 'stream':
  51                             client, address = self.server.accept()
  52                             client.setblocking(0) #pylint: disable=no-member
  53                             conn = dss_connection.Connection(client, address, self.rpc_processor)
  54                             inputs.append(conn)
  55                             logging.info("Accepted connection from %r" % address)
  56                         else:
  57                             data, address = self.server.recvfrom(4096)
  58                             dss_connection.Connection.recv_dgram(self.server, data, address, self.rpc_processor)
  59                     else:
  60                         result = s.recv()
  61                         if not result:
  62                             inputs.remove(s)
  63             except (SystemExit, KeyboardInterrupt):
  64                 break
  65             except select.error as e:
  66                 if e.args[0] == errno.EINTR:
  67                     break
  68         logging.info("Server stopping")
  69         self.remove_uds()
  70
  71     def remove_uds(self):
  72         try:
  73             os.unlink(self.uds)
  74         except OSError:
  75             pass
  76
  77     def shutdown(self):
  78         logging.info("Shutting down tcp server")
  79         self.stopped = True