RabbitMQ connections causes cardinality explosion

[phemmer]

Directions

Bug report

Relevant telegraf.conf:

[[inputs.rabbitmq]]
  url = "http://localhost:15672"

System info:

Telegraf master (17b307a)
CentOS/7

Steps to reproduce:

1. Start telegraf

Expected behavior:

Telegraf output should contain a relatively stable number of series.

Actual behavior:

Telegraf outputs a new series every time a client connects to RabbitMQ because it has a tag called connection which contains the TCP tuple (client-ip + client-port + server-ip + server-port)

Additional info:

Change introduced by #1908

[sparrc]

sigh, I'll revert #1908