Nagios notifications for Slack, with formatted messages :

• Set up an incoming webhook integration in your Slack workspace.
  ( https://my.slack.com/services/new/incoming-webhook/ )

• Copy the two scripts to your plugin directory. (location may vary)

• Edit the Slack URLs to reflect the webhooks you created in Slack.

• Define the new notification commands in Nagios. (example in slack_commands.cfg, modify paths as required)

• Set up a new contact to use the new host and service notification commands.