gistfile1.txt

# /etc/collectd/collectd.conf
LoadPlugin exec
<Plugin exec>
  NotificationExec "sys:sys" "/usr/bin/slack.sh"
</Plugin>

# /usr/bin/slack.sh
#!/bin/bash -x
PATH=/usr/bin:/bin:$PATH
input=$(cat)
echo $input | tee -a /tmp/collectd.log
Plugin=$(field Plugin)
#PluginInstance=$(field PluginInstance)
#Type=$(field Type)
#TypeInstance=$(field TypeInstance)
Host=$(field Host)
#Severity=$(field Severity)
#Time=$(field Time)
Message=$(sed '1,/^$/d' <<< "$input")
data_empty=$(uptime)
host=$(hostname -f)
curl -X POST --data-urlencode 'payload={"channel": "#autoscale", "username": "\'"${host}"\'", "text": "\'"${Message}"\'", "icon_emoji": ":ghost:"}' https://SLACK_URL

# /tmp/collectd.log
==> /tmp/collectd.log <==
Severity: WARNING Time: 1473161973.966 Host: localhost Plugin: load Type: load DataSource: shortterm CurrentValue: 1.740000e+00 WarningMin: nan WarningMax: 1.000000e+00 FailureMin: nan FailureMax: 2.000000e+00 Host localhost, plugin load type load: Data source "shortterm" is currently 1.740000. That is above the warning threshold of 1.000000.