Issue #200 - Move SLE class vars to instance vars

When running more than one class that inherits from SLE, _state, _handlers,
_data_queue, and _invoke_id become shared. The most common issue this
creates is if data is being inserted into the data queue that is being
shared. Data will be given to any of the children even if the PDU
does not match what the child knows about.

By making these instance level attributes data is kept confined
to the individual member and is not shared.

Additionally, if a socket is closed abruptly, the _state should
be reset to "unbound" because the only way to reset it would be
to destroy the object. The socket should be reset to None
if it is ever closed.

patch_all is not required as the only thing being monkey patched
for gevents is time. By running patch_all, issues arise when running
non-gevent queues in calling applications.

_telem_sock should only be created when connecting, not on class instantiation

Fixes #200

ait/dsn/sle/common.py

@@ -58,7 +58,7 @@
 import gevent.queue
 import gevent.socket
 import gevent.select
-import gevent.monkey; gevent.monkey.patch_all()
+import gevent.monkey; gevent.monkey.patch_time()
 
 import pyasn1.error
 from pyasn1.codec.ber.encoder import encode
@@ -92,13 +92,13 @@ class SLE(object):
     for interfacing with SLE.
 
     '''
-    _state = 'unbound'
-    _handlers = defaultdict(list)
-    _data_queue = gevent.queue.Queue()
-    _invoke_id = 0
 
     def __init__(self, *args, **kwargs):
         ''''''
+        self._state = 'unbound'
+        self._handlers = defaultdict(list)
+        self._data_queue = gevent.queue.Queue()
+        self._invoke_id = 0
         self._downlink_frame_type = ait.config.get('dsn.sle.downlink_frame_type',
                                                    kwargs.get('downlink_frame_type', 'TMTransFrame'))
         self._heartbeat = ait.config.get('dsn.sle.heartbeat',
@@ -117,7 +117,6 @@ def __init__(self, *args, **kwargs):
                                              kwargs.get('peer_password', None))
         self._responder_port = ait.config.get('dsn.sle.responder_port',
                                               kwargs.get('responder_port', 'default'))
-        self._telem_sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
         self._auth_level = ait.config.get('dsn.sle.auth_level',
                                           kwargs.get('auth_level', 'none'))
 
@@ -166,9 +165,11 @@ def send(self, data):
             for i in writeable:
                 i.sendall(data)
         except socket.error as e:
+            self._state = 'unbound'
             if e.errno == errno.ECONNRESET:
                 ait.core.log.error('Socket connection lost to DSN')
                 self._socket.close()
+                self._socket = None
             else:
                 ait.core.log.error('Unexpected error encountered when sending data. Aborting ...')
                 raise e
@@ -306,6 +307,8 @@ def connect(self):
             ait.core.log.error('Connection failure with DSN. Aborting ...')
             raise Exception('Unable to connect to DSN through any provided hostnames.')
 
+        self._telem_sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
+        ait.core.log.info("Starting conn monitor for %s", type(self))
         self._conn_monitor = gevent.spawn(conn_handler, self)
         self._data_processor = gevent.spawn(data_processor, self)
 
@@ -335,7 +338,9 @@ def disconnect(self):
         greenlets for monitoring and processing data.
         '''
         self._socket.close()
+        self._socket = None
         self._telem_sock.close()
+        self._telem_sock = None
         self._conn_monitor.kill()
         self._data_processor.kill()
 

setup.py

@@ -26,7 +26,7 @@
 
 setup(
     name = 'ait-dsn',
-    version = '2.0.1-rc1',
+    version = '2.0.2',
     description  = description,
     long_description = long_description,
     long_description_content_type = 'text/x-rst',