test.py

#!/usr/bin/env python
from __future__ import print_function
import os
import fnmatch
import time
import sys

from vpp_papi import VPP

simple_counter_type = [
    'VNET_INTERFACE_COUNTER_DROP',
    'VNET_INTERFACE_COUNTER_PUNT',
    'VNET_INTERFACE_COUNTER_IP4',
    'VNET_INTERFACE_COUNTER_IP6',
    'VNET_INTERFACE_COUNTER_RX_NO_BUF',
    'VNET_INTERFACE_COUNTER_RX_MISS',
    'VNET_INTERFACE_COUNTER_RX_ERROR',
    'VNET_INTERFACE_COUNTER_TX_ERROR',
    'VNET_INTERFACE_COUNTER_MPLS',
    'VNET_N_SIMPLE_INTERFACE_COUNTER']

combined_counter_type = [
    'VNET_INTERFACE_COUNTER_RX',
    'VNET_INTERFACE_COUNTER_RX_UNICAST',
    'VNET_INTERFACE_COUNTER_RX_MULTICAST',
    'VNET_INTERFACE_COUNTER_RX_BROADCAST',
    'VNET_INTERFACE_COUNTER_TX',
    'VNET_INTERFACE_COUNTER_TX_UNICAST',
    'VNET_INTERFACE_COUNTER_TX_MULTICAST',
    'VNET_INTERFACE_COUNTER_TX_BROADCAST',
    'VNET_N_COMBINED_INTERFACE_COUNTER']


# event handler function to handle reply messages
# it handle two type of message currently
# received value is a struct that could be parsed
def papi_event_handler(msgname, result):
    idx = 0
    if msgname == 'vnet_interface_combined_counters':
        values = []
        # format string will let you to print output by specific format,
        # {0:^11s} means 0 args of format function, it's type is string and maximum length is 11. ^ means align center.
        print('{0:^11s}{1:^40s}{2:^40s}{3:^20s}{4:^20s}'.format('sw_if_index', 'Counter', 'Type', 'Packets', 'Bytes'))
        print('=' * 131)
        for row in result.data:
            print('{0:^11d}{1:^40s}{2:^40s}{3:^20d}{4:^20d}'.format(idx, msgname, combined_counter_type[result.vnet_counter_type], row.packets,
                                                                    row.bytes))
            values.append((row.packets, row.bytes))
            idx += 1

    elif msgname == 'vnet_interface_simple_counters':
        values = []
        # format string will let you to print output by specific format,
        # {0:^11s} means 0 args of format function, it's type is string and maximum length is 11. ^ means align center.
        print('{0:^11s}{1:^40s}{2:^40s}{3:^20s}'.format('sw_if_index', 'Counter', 'Type', 'Packets'))
        print('=' * 111)
        for row in result.data:
            print('{0:^11d}{1:^40s}{2:^40s}{3:^20d}'.format(idx, msgname, simple_counter_type[result.vnet_counter_type], row))

            values.append(row)
            idx += 1

    print()

# set the LD_LIBRARY_PATH such that it points to the directory containing libvppapiclient.so
os.environ['LD_LIBRARY_PATH'] = '/usr/lib/x86_64-linux-gnu/'

# directory containing all the json api files.
# if vpp is installed on the system, these will be in /usr/share/vpp/api/
vpp_json_dir = '/usr/share/vpp/api/'

# construct a list of all the json api files
jsonfiles = []
for root, dirnames, filenames in os.walk(vpp_json_dir):
    for filename in fnmatch.filter(filenames, '*.api.json'):
        jsonfiles.append(os.path.join(vpp_json_dir, filename))

if not jsonfiles:
    print('Error: no json api files found')
    sys.exit(-1)

# use all those files to create vpp.
# Note that there will be no vpp method available before vpp.connect()
vpp = VPP(jsonfiles)
rv = vpp.connect("test_papi")
# print(rv)

# print all specification (variables and functions) that exist in vpp.api
# for func in dir(vpp.api):
#     print(func)
# print()

interface_details = vpp.api.sw_interface_dump()

# set program asynchronous
async = True

# register an event handler to receive reply messages of an api
rv = vpp.register_event_callback(papi_event_handler)

# enable want_stats api in vpp to receive stats
rv = vpp.api.want_stats(enable_disable=True)
# print(rv)

# lifetime of program
time.sleep(10)

# enable want_stats api in vpp to receive stats
rv = vpp.api.want_stats(enable_disable=False)
# print(rv)

# disconnect from vpp
rv = vpp.disconnect()
# print(rv)

sys.exit(rv)