metrics-disk-capacity doesn't parse LVM volumes correctly

[madAndroid]

Hi,

When using the metrics-disk-capacity check with LVM volumes, we're seeing the following metrics being produced:

user-infradev-influx-i30a296b8.sensu.infradev.influx.disk.xvda1.iused 117669 1464013462
user-infradev-influx-i30a296b8.sensu.infradev.influx.disk.xvda1.iavail 33433051 1464013462
user-infradev-influx-i30a296b8.sensu.infradev.influx.disk.xvda1.icapacity 1 1464013462
user-infradev-influx-i30a296b8.sensu.infradev.influx.disk.mapper/influx-influx.iused 32 1464013462
user-infradev-influx-i30a296b8.sensu.infradev.influx.disk.mapper/influx-influx.iavail 99614688 1464013462
user-infradev-influx-i30a296b8.sensu.infradev.influx.disk.mapper/influx-influx.icapacity 1 1464013462

This works 'okay' on Graphite hosts, since it then uses the / in the name to push the metric into another tier, but it get's completely dropped on Influxdb - it seems as though the metric name can't get parsed if it contains a forward slash... is this perhaps something I should be handling in Influx?

I can submit a PR to adjust the behaviour of this plugin, but that's probably a breaking change, and seems like the wrong approach.

[eheydrick]

Hmm, that would break on influxdb. Perhaps /'s should optionally be turned into underscores.

[madAndroid]

I think that's a sensible suggestion; it would probably fix our issue with metrics being silently dropped.

[majormoses]

@madAndroid can you please put together a pr for this?

[madAndroid]

We're no longer collecting metrics via Sensu for InfluxDB - we're using the suggested Influx collector - Telegraf. It's best that someone else pick this up, I just don't have the time to implement this at the moment, and we no longer have a need for it.