initial support for asyncio network transport added

6 files changed, 253 insertions, 0 deletions

diff --git a/pysnmp/carrier/asyncio/__init__.py b/pysnmp/carrier/asyncio/__init__.py
new file mode 100644
index 0000000..ac0b2c0
--- /dev/null
+++ b/pysnmp/carrier/asyncio/__init__.py
@@ -0,0 +1 @@
+# This file is necessary to make this directory a package.

diff --git a/pysnmp/carrier/asyncio/base.py b/pysnmp/carrier/asyncio/base.py
new file mode 100644
index 0000000..192343f
--- /dev/null
+++ b/pysnmp/carrier/asyncio/base.py
@@ -0,0 +1,35 @@
+#
+# Copyright (C) 2014, Zebra Technologies
+# Authors: Matt Hooks <me@matthooks.com>
+#          Zachary Lorusso <zlorusso@gmail.com>
+#
+# Redistribution and use in source and binary forms, with or without 
+# modification, are permitted provided that the following conditions are met:
+#
+# * Redistributions of source code must retain the above copyright notice,
+#   this list of conditions and the following disclaimer.
+#
+# * Redistributions in binary form must reproduce the above copyright
+#   notice, this list of conditions and the following disclaimer in the 
+#   documentation and/or other materials provided with the distribution.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
+# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
+# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 
+# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
+# IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 
+# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF 
+# THE POSSIBILITY OF SUCH DAMAGE.
+#
+from pysnmp.carrier.asyncio.dispatch import AsyncioDispatcher
+from pysnmp.carrier.base import AbstractTransport
+
+class AbstractAsyncioTransport(AbstractTransport):
+    protoTransportDispatcher = AsyncioDispatcher
+    """Base Asyncio Transport, to be used with AsyncioDispatcher"""
+    def __init__(self):
+        self._writeQ = []
diff --git a/pysnmp/carrier/asyncio/dgram/__init__.py b/pysnmp/carrier/asyncio/dgram/__init__.py
new file mode 100644
index 0000000..ac0b2c0
--- /dev/null
+++ b/pysnmp/carrier/asyncio/dgram/__init__.py
@@ -0,0 +1 @@
+# This file is necessary to make this directory a package.

diff --git a/pysnmp/carrier/asyncio/dgram/base.py b/pysnmp/carrier/asyncio/dgram/base.py
new file mode 100644
index 0000000..c45e358
--- /dev/null
+++ b/pysnmp/carrier/asyncio/dgram/base.py
@@ -0,0 +1,75 @@
+#
+# Copyright (C) 2014, Zebra Technologies
+# Authors: Matt Hooks <me@matthooks.com>
+#          Zachary Lorusso <zlorusso@gmail.com>
+#
+# Redistribution and use in source and binary forms, with or without 
+# modification, are permitted provided that the following conditions are met:
+#
+# * Redistributions of source code must retain the above copyright notice,
+#   this list of conditions and the following disclaimer.
+#
+# * Redistributions in binary form must reproduce the above copyright
+#   notice, this list of conditions and the following disclaimer in the 
+#   documentation and/or other materials provided with the distribution.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
+# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
+# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 
+# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
+# IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 
+# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF 
+# THE POSSIBILITY OF SUCH DAMAGE.
+#
+from pysnmp.carrier.asyncio.base import AbstractAsyncioTransport
+from pysnmp.carrier import error
+from pysnmp import debug
+try:
+    import asyncio
+except ImportError:
+    from pysnmp.error import PySnmpError
+    raise PySnmpError('The asyncio transport is not available')
+
+loop = asyncio.get_event_loop()
+
+class DgramAsyncioProtocol(asyncio.DatagramProtocol, AbstractAsyncioTransport):
+    """Base Asyncio datagram Transport, to be used with AsyncioDispatcher"""
+    transport = None
+
+    def datagram_received(self, datagram, transportAddress):
+        if self._cbFun is None:
+            raise error.CarrierError('Unable to call cbFun')
+        else:
+            loop.call_soon(self._cbFun, self, transportAddress, datagram)
+
+    def connection_made(self, transport):
+        self.transport = transport
+        debug.logger & debug.flagIO and debug.logger('connection_made: invoked')
+        while self._writeQ:
+            outgoingMessage, transportAddress = self._writeQ.pop(0)
+            debug.logger & debug.flagIO and debug.logger('connection_made: transportAddress %r outgoingMessage %s' %
+                                                         (transportAddress, debug.hexdump(outgoingMessage)))
+            try:
+                self.transport.sendto(outgoingMessage, transportAddress)
+            except Exception as err:
+                raise error.CarrierError() from err
+
+    def connection_lost(self, exc):
+        debug.logger & debug.flagIO and debug.logger('connection_lost: invoked')
+
+    def sendMessage(self, outgoingMessage, transportAddress):
+        debug.logger & debug.flagIO and debug.logger('sendMessage: %s transportAddress %r outgoingMessage %s' % (
+            (self.transport is None and "queuing" or "sending"),
+            transportAddress, debug.hexdump(outgoingMessage)
+        ))
+        if self.transport is None:
+            self._writeQ.append((outgoingMessage, transportAddress))
+        else:
+            try:
+                self.transport.sendto(outgoingMessage, transportAddress)
+            except Exception as err:
+                raise error.CarrierError() from err
diff --git a/pysnmp/carrier/asyncio/dgram/udp.py b/pysnmp/carrier/asyncio/dgram/udp.py
new file mode 100644
index 0000000..d29981a
--- /dev/null
+++ b/pysnmp/carrier/asyncio/dgram/udp.py
@@ -0,0 +1,63 @@
+#
+# Copyright (C) 2014, Zebra Technologies
+# Authors: Matt Hooks <me@matthooks.com>
+#          Zachary Lorusso <zlorusso@gmail.com>
+#
+# Redistribution and use in source and binary forms, with or without 
+# modification, are permitted provided that the following conditions are met:
+#
+# * Redistributions of source code must retain the above copyright notice,
+#   this list of conditions and the following disclaimer.
+#
+# * Redistributions in binary form must reproduce the above copyright
+#   notice, this list of conditions and the following disclaimer in the 
+#   documentation and/or other materials provided with the distribution.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
+# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
+# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 
+# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
+# IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 
+# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF 
+# THE POSSIBILITY OF SUCH DAMAGE.
+#
+from pysnmp.carrier.asyncio.dgram.base import DgramAsyncioProtocol
+from pysnmp.carrier import error
+try:
+    import asyncio
+except ImportError:
+    from pysnmp.error import PySnmpError
+    raise PySnmpError('The asyncio transport is not available')
+
+loop = asyncio.get_event_loop()
+
+domainName = snmpUDPDomain = (1, 3, 6, 1, 6, 1, 1)
+
+class UdpAsyncioTransport(DgramAsyncioProtocol):
+    # AbstractAsyncioTransport API
+
+    def openClientMode(self, iface=('0.0.0.0', 0)):
+        try:
+            c = loop.create_datagram_endpoint(lambda: self, local_addr=iface)
+            self._lport = asyncio.async(c)
+        except Exception as err:
+            raise error.CarrierError() from err
+        return self
+
+    def openServerMode(self, iface=('0.0.0.0', 161)):
+        try:
+            c = loop.create_datagram_endpoint(lambda: self, local_addr=iface)
+            self._lport = asyncio.async(c)
+        except Exception as err:
+            raise error.CarrierError() from err
+        return self
+
+    def closeTransport(self):
+        self._lport.cancel()
+        DgramAsyncioProtocol.closeTransport(self)
+
+UdpTransport = UdpAsyncioTransport
diff --git a/pysnmp/carrier/asyncio/dispatch.py b/pysnmp/carrier/asyncio/dispatch.py
new file mode 100644
index 0000000..7b0b72f
--- /dev/null
+++ b/pysnmp/carrier/asyncio/dispatch.py
@@ -0,0 +1,78 @@
+#
+# Copyright (C) 2014, Zebra Technologies
+# Authors: Matt Hooks <me@matthooks.com>
+#          Zachary Lorusso <zlorusso@gmail.com>
+#
+# Redistribution and use in source and binary forms, with or without 
+# modification, are permitted provided that the following conditions are met:
+#
+# * Redistributions of source code must retain the above copyright notice,
+#   this list of conditions and the following disclaimer.
+#
+# * Redistributions in binary form must reproduce the above copyright
+#   notice, this list of conditions and the following disclaimer in the 
+#   documentation and/or other materials provided with the distribution.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
+# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
+# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 
+# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
+# IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 
+# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF 
+# THE POSSIBILITY OF SUCH DAMAGE.
+#
+from pysnmp.carrier.base import AbstractTransportDispatcher
+try:
+    import asyncio
+except ImportError:
+    from pysnmp.error import PySnmpError
+    raise PySnmpError('The asyncio transport is not available')
+
+loop = asyncio.get_event_loop()
+
+class AsyncioDispatcher(AbstractTransportDispatcher):
+    """AsyncioDispatcher based on asyncio event loop"""
+    def __init__(self, *args, **kwargs):
+        AbstractTransportDispatcher.__init__(self)
+        self.__transportCount = 0
+        if 'timeout' in kwargs:
+            self.setTimerResolution(kwargs['timeout'])
+        self.loopingcall = None
+
+    @asyncio.coroutine
+    def handle_timeout(self):
+        while True:
+            yield from asyncio.sleep(self.getTimerResolution())
+            self.handleTimerTick(loop.time())
+
+    def runDispatcher(self, timeout=0.0):
+        if not loop.is_running():
+            try:
+                loop.run_forever()
+            except KeyboardInterrupt:
+                raise
+            except Exception as err:
+                raise PySnmpError('event loop error') from err
+
+    def registerTransport(self, tDomain, transport):
+        if self.loopingcall is None and self.getTimerResolution() > 0:
+            self.loopingcall = asyncio.async(self.handle_timeout())
+        AbstractTransportDispatcher.registerTransport(
+            self, tDomain, transport
+            )
+        self.__transportCount = self.__transportCount + 1
+
+    def unregisterTransport(self, tDomain):
+        t = AbstractTransportDispatcher.getTransport(self, tDomain)
+        if t is not None:
+            AbstractTransportDispatcher.unregisterTransport(self, tDomain)
+            self.__transportCount = self.__transportCount - 1
+
+        # The last transport has been removed, stop the timeout
+        if self.__transportCount == 0 and not self.loopingcall.done():
+            self.loopingcall.cancel()
+            self.loopingcall = None