It's useful to know what StatsD metrics you're sending locally before it hits your production metrics sink. Getting a metric name, namespace, or data type incorrect in production is annoying, and it can mess up metrics for a certain time window after it's fixed.

Assuming this example that sends a metric:

from time import sleep
import statsd

c = statsd.StatsClient("localhost", 8125)

while True:
    sleep(2)
    c.timing("stats.timed", 1)
    c.incr("foo")

You can follow what it's sending locally by using netcat to listen for the UDP packets:

$ nc -ulv -p 8125
Received packet from 127.0.0.1:58916 -> 127.0.0.1:8125 (local)
stats.timed:1.000000|msfoo:1|c

$ nc -ulv starts nc in UDP listening mode:

  • -u = UDP
  • -l = Listen
  • -v = Verbose Logs
  • -p = Port of your StatsD emitter