From 1bf70e6c3a5346966c25e0a1ff492945b25d3f80 Mon Sep 17 00:00:00 2001 From: Donald Hunter Date: Fri, 18 Oct 2024 10:32:28 +0100 Subject: tools/net/ynl: improve async notification handling The notification handling in ynl is currently very simple, using sleep() to wait a period of time and then handling all the buffered messages in a single batch. This patch changes the notification handling so that messages are processed as they are received. This makes it possible to use ynl as a library that supplies notifications in a timely manner. - Change check_ntf() to be a generator that yields 1 notification at a time and blocks until a notification is available. - Use the --sleep parameter to set an alarm and exit when it fires. This means that the CLI has the same interface, but notifications get printed as they are received: ./tools/net/ynl/cli.py --spec --subscribe [ --sleep ] Here is an example python snippet that shows how to use ynl as a library for receiving notifications: ynl = YnlFamily(f"{dir}/rt_route.yaml") ynl.ntf_subscribe('rtnlgrp-ipv4-route') for event in ynl.check_ntf(): handle(event) Signed-off-by: Donald Hunter Tested-by: Kory Maincent Link: https://patch.msgid.link/20241018093228.25477-1-donald.hunter@gmail.com Signed-off-by: Paolo Abeni --- tools/net/ynl/lib/ynl.py | 49 ++++++++++++++++++++++++++++-------------------- 1 file changed, 29 insertions(+), 20 deletions(-) (limited to 'tools/net/ynl/lib/ynl.py') diff --git a/tools/net/ynl/lib/ynl.py b/tools/net/ynl/lib/ynl.py index c22c22bf2cb7..92f85698c50e 100644 --- a/tools/net/ynl/lib/ynl.py +++ b/tools/net/ynl/lib/ynl.py @@ -12,6 +12,8 @@ import sys import yaml import ipaddress import uuid +import queue +import time from .nlspec import SpecFamily @@ -489,7 +491,7 @@ class YnlFamily(SpecFamily): self.sock.setsockopt(Netlink.SOL_NETLINK, Netlink.NETLINK_GET_STRICT_CHK, 1) self.async_msg_ids = set() - self.async_msg_queue = [] + self.async_msg_queue = queue.Queue() for msg in self.msgs.values(): if msg.is_async: @@ -903,32 +905,39 @@ class YnlFamily(SpecFamily): msg['name'] = op['name'] msg['msg'] = attrs - self.async_msg_queue.append(msg) + self.async_msg_queue.put(msg) - def check_ntf(self): + def check_ntf(self, interval=0.1): while True: try: reply = self.sock.recv(self._recv_size, socket.MSG_DONTWAIT) - except BlockingIOError: - return + nms = NlMsgs(reply) + self._recv_dbg_print(reply, nms) + for nl_msg in nms: + if nl_msg.error: + print("Netlink error in ntf!?", os.strerror(-nl_msg.error)) + print(nl_msg) + continue + if nl_msg.done: + print("Netlink done while checking for ntf!?") + continue - nms = NlMsgs(reply) - self._recv_dbg_print(reply, nms) - for nl_msg in nms: - if nl_msg.error: - print("Netlink error in ntf!?", os.strerror(-nl_msg.error)) - print(nl_msg) - continue - if nl_msg.done: - print("Netlink done while checking for ntf!?") - continue + decoded = self.nlproto.decode(self, nl_msg, None) + if decoded.cmd() not in self.async_msg_ids: + print("Unexpected msg id while checking for ntf", decoded) + continue - decoded = self.nlproto.decode(self, nl_msg, None) - if decoded.cmd() not in self.async_msg_ids: - print("Unexpected msg id done while checking for ntf", decoded) - continue + self.handle_ntf(decoded) + except BlockingIOError: + pass - self.handle_ntf(decoded) + try: + yield self.async_msg_queue.get_nowait() + except queue.Empty: + try: + time.sleep(interval) + except KeyboardInterrupt: + return def operation_do_attributes(self, name): """ -- cgit v1.2.3