sonic-buildimage/dockers/docker-sflow/port_index_mapper.py
padmanarayana 5cacc2004c
Add a port index mapper service for sFlow (#4794)
* Add a port index mapper service for sFlow
2020-06-23 22:23:08 -07:00

115 lines
3.2 KiB
Python
Executable File

#!/usr/bin/env python
""" port_index_mapper
A mapper service that watches for NetLink NEWLINK and DELLINKs
to construct a PORT_INDEX_TABLE in state DB which includes the
interface name, the interface index and the ifindex.
Note : Currently supports only interfaces supported by port_util.
"""
import os
import sys
import syslog
import signal
import traceback
from pyroute2 import IPDB
from pyroute2.iproute import RTM_NEWLINK, RTM_DELLINK
from swsssdk import SonicV2Connector, port_util
PORT_INDEX_TABLE_NAME = 'PORT_INDEX_TABLE'
SYSLOG_IDENTIFIER = 'port_index_mapper'
ipdb = None
state_db = None
def set_port_index_table_entry(key, index, ifindex):
state_db.set(state_db.STATE_DB, key, 'index', index)
state_db.set(state_db.STATE_DB, key, 'ifindex', ifindex)
def interface_callback(ipdb, nlmsg, action):
global state_db
try:
msgtype = nlmsg['header']['type']
if (msgtype != RTM_NEWLINK and msgtype != RTM_DELLINK):
return
# filter out unwanted messages
change = nlmsg['change']
if (change != 0xFFFFFFFF):
return
attrs = nlmsg['attrs']
for list in attrs:
if list[0] == 'IFLA_IFNAME':
ifname = list[1]
break
else:
return
# Extract the port index from the interface name
index = port_util.get_index_from_str(ifname)
if index is None:
return
_hash = '{}|{}'.format(PORT_INDEX_TABLE_NAME, ifname)
if msgtype == RTM_NEWLINK:
set_port_index_table_entry(_hash, str(index), nlmsg['index'])
elif msgtype == RTM_DELLINK:
state_db.delete(state_db.STATE_DB, _hash)
except Exception, e:
t = sys.exc_info()[2]
traceback.print_tb(t)
syslog.syslog(syslog.LOG_CRIT, "%s" % str(e))
os.kill(os.getpid(), signal.SIGTERM)
def main():
global state_db, ipdb
state_db = SonicV2Connector(host='127.0.0.1')
state_db.connect(state_db.STATE_DB, False)
ipdb = IPDB()
# Initialize the table at startup.
ifnames = ipdb.by_name.keys()
for ifname in ifnames:
index = port_util.get_index_from_str(ifname)
if index is None:
continue
ifindex = ipdb.interfaces[ifname]['index']
_hash = '{}|{}'.format(PORT_INDEX_TABLE_NAME, ifname)
set_port_index_table_entry(_hash, str(index), str(ifindex))
ipdb.register_callback(interface_callback)
signal.pause()
def signal_handler(signum, frame):
syslog.syslog(syslog.LOG_NOTICE, "got signal %d" % signum)
sys.exit(0)
if __name__ == '__main__':
rc = 0
try:
syslog.openlog(SYSLOG_IDENTIFIER)
signal.signal(signal.SIGTERM, signal_handler)
signal.signal(signal.SIGINT, signal_handler)
main()
except Exception, e:
t = sys.exc_info()[2]
traceback.print_tb(t)
syslog.syslog(syslog.LOG_CRIT, "%s" % str(e))
rc = -1
finally:
if ipdb is not None:
ipdb.release()
else:
syslog.syslog(syslog.LOG_ERR, "ipdb undefined in signal_handler")
syslog.closelog()
sys.exit(rc)