Webhook to delete specific hosts in a rancher 1.6 environment
In a perfect container environment every host is transient. If a host does not currently do work it can be thrown away and later replaced by a new one should it become necessary.
Combining Prometheus and Grafana allows identifying empty hosts to be thrown away and to send alerts to webhooks with the hosts it found. (Note: make sure to activate reminders because grafana does not support alerts for multiple series yet but reminders will show the current hosts)
This webhook is written as target for the grafana alert for an empty host, causing it to be deleted.
docker/docker-compose.yml is used for testing purposes. Note that is actually builds the current app as Image so you will have to rebuild to test changes you made.
docker-compose -f docker/docker-compose.yml up --build -d
In addition you need a docker/.env file with at least the following content:
APP_SECRET=somestring
To actually delete hosts use the following in the .env file or your docker containers environment
APP_DELETER=rancher-cli
RANCHER_URL=URL
RANCHER_ACCESS_KEY=access_key
RANCHER_SECRET_KEY=secret_key
This expects a rancher environment api key and a environment specific url
To instead send slack messages for each request use
APP_DELETER=slack
SLACK_URL=webhook-url
Creating the slack webhook url is outside the scope of this readme. Please see the slack documentation about incoming webhooks instead.