Slack

Generate slack incoming webhook URL

To post a slack notification, that you need to generate an incoming webhook URL. To generate the URL, follow these steps: Incoming webhooks for Slack.

Configuring a slack destination

You can configure a slack destination in the Destinations tab. As part of the configuration, enter the Slack Incoming Webhook URL. Create a subscription to associate the slack destination to a topic.

Configuring a slack subscription

You can add attachment color to individual slack subscription based on hex code, for example, "#0000FF" for blue.

How a slack notification from Event Notifications looks

Event notification generates slack notifications from incoming payload. The template event notification use to send to slack looks like following -

{
   "text": "*{{event.ibmendefaultshort}}*",
   "attachments": [{
      "color": "{{config.subscription.attachment_color}}",
      "blocks": [{
         "type": "section",
         "text": {
            "type": "mrkdwn",
            "text": "{{event.ibmendefaultlong}}"
         }
      },
      {
         "type": "divider"
      },
      {
         "type": "section",
         "text": {
            "type": "mrkdwn",
            "text": "```{{event.data}} ```"
         }
      }
      ]
   }]
}

Here -

ibmendefaultshort is the default short payload that is provided in the incoming payload. attachment_color is the color that is applied to the notification, which was provided during subscription. ibmendefaultlong is the default long payload that is provided in the incoming payload. data is the data JSON provided in the incoming payload and format as JSON in the slack notification.

Testing a Slack destination configuration

You can test a Slack destination in the options menu provided againts the destination. You can effortlessly test a destination, whether the provided configuration is correct or not with a single click.

For more information on testing a destination, see here.

Slack retry policy

When publishing a slack notification, issues such as network errors and application glitches can cause the requests to fail. A retry is used to provide resiliency to external requests. Attempt to retry the requests in such situations by using the following values:

• Limit = 60 seconds: total time that the service retries.
• Step = 5 seconds: after each failure, the service waits 5 seconds before retrying. This delay prevents bombarding of the external services (webhook).

In addition, the following timeout conditions cause the slack call to fail:

• A connection timeout of 10 seconds
• A response timeout of 60 seconds

If a call to the Slack webhook URL fails even after retry attempts, the notification is lost.