panic: division by zero in statsd allowed_pending_messages

[arussellsaw]

Bug report

panic on statsd input where allowed_pending_messages < 1

minimal PR, looking for quick wins for hacktoberfest 😸

found via a tweet from a pal: https://twitter.com/rubynerd/status/775399499128856576

Relevant telegraf.conf:

[[inputs.statsd]]
  allowed_pending_messages = 0

System info:

telegraf 1.0, MacOS 10.10

Steps to reproduce:

1. setup statsd input with 0 allowed_pending_messages
2. get input to start dropping messages

Expected behavior:

no panics, either automatically adjusting value or quitting cleanly with error message

Actual behavior:

a panic of division by zero

Proposal:

Current behavior:

panic when dropping messages

Desired behavior:

adjust pending messages to at least 1, warn the user

[sparrc]

TFW users tweet about issues rather than opening bug reports.....

it's already fixed in 1.0.1: #1785

[arussellsaw]

oh no! i thought i'd gotten here in time for hacktoberfest.

[sparrc]

sorry mate, appreciate the effort though :), now that I think about it I think it could still panic if a user actively set the value to 0....maybe there is still a bug?

the PR I linked to just fixed it so that not setting a value wouldn't default to 0

[arussellsaw]

i have a PR ready with a warn and adjust to 1 if that's the desired behaviour

[arussellsaw]

#1870