From b471daf85b07d0ca072a8d7ec482a25401a67399 Mon Sep 17 00:00:00 2001 From: Bob McElrath Date: Thu, 19 Jan 2017 17:06:52 -0500 Subject: [PATCH] Adddress nits, use asyncio signal handling, create_task --- contrib/zmq/zmq_sub.py | 32 +++++++++++++++++++++++--------- contrib/zmq/zmq_sub3.4.py | 36 +++++++++++++++++++++++++++--------- 2 files changed, 50 insertions(+), 18 deletions(-) diff --git a/contrib/zmq/zmq_sub.py b/contrib/zmq/zmq_sub.py index 4839f401b..33a6b4ce6 100755 --- a/contrib/zmq/zmq_sub.py +++ b/contrib/zmq/zmq_sub.py @@ -3,12 +3,29 @@ # Distributed under the MIT software license, see the accompanying # file COPYING or http://www.opensource.org/licenses/mit-license.php. -# A blocking example using python 2.7 can be obtained from the git history: -# https://github.com/bitcoin/bitcoin/blob/37a7fe9e440b83e2364d5498931253937abe9294/contrib/zmq/zmq_sub.py +""" + ZMQ example using python3's asyncio + + Bitcoin should be started with the command line arguments: + bitcoind -testnet -daemon \ + -zmqpubhashblock=tcp://127.0.0.1:28332 \ + -zmqpubrawtx=tcp://127.0.0.1:28332 \ + -zmqpubhashtx=tcp://127.0.0.1:28332 \ + -zmqpubhashblock=tcp://127.0.0.1:28332 + + We use the asyncio library here. `self.handle()` installs itself as a + future at the end of the function. Since it never returns with the event + loop having an empty stack of futures, this creates an infinite loop. An + alternative is to wrap the contents of `handle` inside `while True`. + + A blocking example using python 2.7 can be obtained from the git history: + https://github.com/bitcoin/bitcoin/blob/37a7fe9e440b83e2364d5498931253937abe9294/contrib/zmq/zmq_sub.py +""" -import array import binascii -import asyncio, zmq, zmq.asyncio +import asyncio +import zmq +import zmq.asyncio import signal import struct import sys @@ -55,7 +72,8 @@ class ZMQHandler(): asyncio.ensure_future(self.handle()) def start(self): - asyncio.ensure_future(self.handle()) + self.loop.add_signal_handler(signal.SIGINT, self.stop) + self.loop.create_task(self.handle()) self.loop.run_forever() def stop(self): @@ -63,8 +81,4 @@ class ZMQHandler(): self.zmqContext.destroy() daemon = ZMQHandler() -def signal_handler(num, frame): - daemon.stop() - exit(0) -signal.signal(signal.SIGINT, signal_handler) daemon.start() diff --git a/contrib/zmq/zmq_sub3.4.py b/contrib/zmq/zmq_sub3.4.py index bd0c4fb30..a2ff64b29 100755 --- a/contrib/zmq/zmq_sub3.4.py +++ b/contrib/zmq/zmq_sub3.4.py @@ -3,12 +3,33 @@ # Distributed under the MIT software license, see the accompanying # file COPYING or http://www.opensource.org/licenses/mit-license.php. -# A blocking example using python 2.7 can be obtained from the git history: -# https://github.com/bitcoin/bitcoin/blob/37a7fe9e440b83e2364d5498931253937abe9294/contrib/zmq/zmq_sub.py +""" + ZMQ example using python3's asyncio + + Bitcoin should be started with the command line arguments: + bitcoind -testnet -daemon \ + -zmqpubhashblock=tcp://127.0.0.1:28332 \ + -zmqpubrawtx=tcp://127.0.0.1:28332 \ + -zmqpubhashtx=tcp://127.0.0.1:28332 \ + -zmqpubhashblock=tcp://127.0.0.1:28332 + + We use the asyncio library here. `self.handle()` installs itself as a + future at the end of the function. Since it never returns with the event + loop having an empty stack of futures, this creates an infinite loop. An + alternative is to wrap the contents of `handle` inside `while True`. + + The `@asyncio.coroutine` decorator and the `yield from` syntax found here + was introduced in python 3.4 and has been deprecated in favor of the `async` + and `await` keywords respectively. + + A blocking example using python 2.7 can be obtained from the git history: + https://github.com/bitcoin/bitcoin/blob/37a7fe9e440b83e2364d5498931253937abe9294/contrib/zmq/zmq_sub.py +""" -import array import binascii -import asyncio, zmq, zmq.asyncio +import asyncio +import zmq +import zmq.asyncio import signal import struct import sys @@ -56,7 +77,8 @@ class ZMQHandler(): asyncio.ensure_future(self.handle()) def start(self): - asyncio.ensure_future(self.handle()) + self.loop.add_signal_handler(signal.SIGINT, self.stop) + self.loop.create_task(self.handle()) self.loop.run_forever() def stop(self): @@ -64,8 +86,4 @@ class ZMQHandler(): self.zmqContext.destroy() daemon = ZMQHandler() -def signal_handler(num, frame): - daemon.stop() - exit(0) -signal.signal(signal.SIGINT, signal_handler) daemon.start()