Question

I’m new to python and I need to calculate the ‘average speed’ of my network interface(like the tool nload) on a linux machine. The below code is telling me how much bytes have been sent and received. I would appreciate if someone could help me print the average speed of my network interface.

def main():
    rx_bytes, tx_bytes = get_network_bytes('eth0')
    print '%i bytes received' % rx_bytes
    print '%i bytes sent' % tx_bytes

def get_network_bytes(interface):
    for line in open('/proc/net/dev', 'r'):
        if interface in line:
            data = line.split('%s:' % interface)[1].split()
            rx_bytes, tx_bytes = (data[0], data[8])
            return (int(rx_bytes), int(tx_bytes))

if __name__ == '__main__':
    main()

Answer 1

Take your main() and get_network_bytes() and wrap them in a python process:

import subprocess
import time
from daemon import runner
import datetime

class App():
    def __init__(self):
        self.stdin_path = '/dev/null'
        self.stdout_path = '/dev/tty'
        self.stderr_path = '/dev/tty'
        self.pidfile_path =  '/tmp/YOUR_PROCESS_NAME.pid'
        self.pidfile_timeout = 5
    def run(self):

        counter1 = 0
        counter_log = 0
        try:
            while True:

                # INSERT YOUR FUNCTIONS HERE

                # SET YOUR LOOP SLEEP TIMER (IN SECONDS) HERE
                time.sleep(60)

        except Exception, e:
            raise

app = App()
daemon_runner = runner.DaemonRunner(app)
daemon_runner.do_action()

Then run with “python myscript.py start” or stop or restart, the process ID will be printed on the screen. With this running in the background you’ll need to import that script as part of your other program to query it, or you can always have your result print to a temp file each time it loops and then have your other program(s) query that temp file. “There’s a number of different ways to do this”

Edit:

Start with something like this and customize, this is really only one way to go about it, I would suggest another library like psutil rather then messy parsing of ifconfig which only works in linux:

“Make sure to change the interface, I’m using WLAN0 you may be using something different”

The following script will print out to the screen every 60 seconds the average TX and RX rates for that last minute.

import os
import subprocess
import time
from daemon import runner
import datetime
import re 

class App():
    def __init__(self):
        self.stdin_path = '/dev/null'
        self.stdout_path = '/dev/tty'
        self.stderr_path = '/dev/tty'
        self.pidfile_path =  '/tmp/bandwidth_counter.pid'
        self.pidfile_timeout = 5
    def run(self):
        rx_megabits_new = 0
        tx_megabits_new = 0
        try:
                while True:
                        output = subprocess.Popen(['ifconfig', "wlan0"], stdout=subprocess.PIPE).communicate()[0]
                        rx_bytes = re.findall('RX bytes:([0-9]*) ', output)[0]
                        tx_bytes = re.findall('TX bytes:([0-9]*) ', output)[0]
                        rx_megabits = (((int(rx_bytes) * 8) / 1024) / 1024)
                        tx_megabits = (((int(tx_bytes) * 8) / 1024) / 1024)
                        current_rx_usage = rx_megabits - rx_megabits_new
                        current_tx_usage = tx_megabits - tx_megabits_new
                        rx_megabits_new = rx_megabits
                        tx_megabits_new = tx_megabits 
                        print 'average megabits received', current_rx_usage / 60
                        print 'average kilobits received', (current_rx_usage * 1024) / 60
                        print 'average megabits sent', current_tx_usage / 60
                        print 'average kilobits sent', (current_tx_usage * 1024) / 60
                        time.sleep(60)

        except Exception, e:
            raise


app = App()
daemon_runner = runner.DaemonRunner(app)
daemon_runner.do_action()

Again this works with: “python myscript.py start” and stop and restart. You’ll want to add some file open and write rather then print to the screen. I would also suggest that you open your files for writing with gzip.open() to save some space as they will grow large quickly.

Edit:

Here’s the same daemon this time writing to a file /tmp/netstats_counter.log which is a csv containing “tx rate in KB/s over 1 minute intervals, average rx rate in KB/s over 1 minute intervals, unix timestamp”

import os
import subprocess
import time
from daemon import runner
import datetime
import re 

class App():
    def __init__(self):
        self.stdin_path = '/dev/null'
        self.stdout_path = '/dev/tty'
        self.stderr_path = '/dev/tty'
        self.pidfile_path =  '/tmp/twitter_counter.pid'
        self.pidfile_timeout = 5
    def run(self):
        rx_megabits_new = 0
        tx_megabits_new = 0
        try:
                while True:
                        output_csv = open("/tmp/netstats_counter.log", 'a')
                        output = subprocess.Popen(['ifconfig', "wlan0"], stdout=subprocess.PIPE).communicate()[0]

                        rx_bytes = re.findall('RX bytes:([0-9]*) ', output)[0]
                        tx_bytes = re.findall('TX bytes:([0-9]*) ', output)[0]
                        rx_megabits = (((int(rx_bytes) * 8) / 1024) / 1024)
                        tx_megabits = (((int(tx_bytes) * 8) / 1024) / 1024)

                        current_rx_usage = (rx_megabits - rx_megabits_new) / 60
                        current_tx_usage = (tx_megabits - tx_megabits_new) / 60
                        current_rx_usage_kb = current_rx_usage * 1024
                        current_tx_usage_kb = current_tx_usage * 1024

                        rx_megabits_new = rx_megabits
                        tx_megabits_new = tx_megabits 

                        now = str(datetime.datetime.now())

                        col1 = str(current_tx_usage_kb) 
                        col2 = str(current_rx_usage_kb)
                        output_csv.write(col1)
                        output_csv.write(", ")
                        output_csv.write(col2)
                        output_csv.write(", ")
                        output_csv.write(now)
                        output_csv.write("\n")

                        output_csv.close( )


#                       print 'average megabits received', current_rx_usage / 60
#                       print 'average kilobits received', (current_rx_usage * 1024) / 60
#                       print 'average megabits sent', current_tx_usage / 60
#                       print 'average kilobits sent', (current_tx_usage * 1024) / 60


                        time.sleep(60)

        except Exception, e:
            raise


app = App()
daemon_runner = runner.DaemonRunner(app)
daemon_runner.do_action()