Slack Notifications

[leandrok]

Hello, congratulations for this great service
Can you add the ability of sending Slack notifications please?

[camaeel]

@leandrok
Thanks.

Although we don't need such notifications internally it may make sense to have notifications.
I'm hesitating if those should go to "slack-compatible" http webhook or some notification service like SNS. SNS might be more robust than simple http request, on the other hand SNS will be cloud provider specific and node-undertaker is designed to be able to handle nodes running using other infrastructure providers (for now only AWS is implemented).

As a quick workaround and temporary solution, you can try monitoring events that are created after every action taken by node-undertaker. Kube-state-metrics or some event exporters can be helpful.

[leandrok]

Thanks for your feedback. Yes, SNS can be a good option so users have the flexibility of sending the alerts to different targets (email, Slack, webhook) through SNS.. I'll check the metrics export approach. Thanks.

[camaeel]

Another idea could be to utilize metrics exposed by the application. It exposes standard prometheus format metrics, but they are not yet documented.
I created separate ticket to track this issue: #5

[leandrok]

Perfect thanks!

[camaeel]

I updated information about metric that exports node statuses observed.

[camaeel]

Released with v1.1.0