Handling notifications

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Overview

Blnk uses webhooks to send you real-time notifications about crucial transaction events happening in your ledger.

In this guide, you’ll learn how Blnk sends notifications and how to handle error notifications through Slack.

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Supported events

Blnk sends webhook notifications for four main events in your Blnk Ledger.

1. transaction.applied: This event is sent when a transaction has been processed and applied to the participating balances. It signifies the completion of a transaction’s lifecycle. See also → Record a transaction.

2. transaction.inflight: This event is sent when a transaction’s status has been updated to INFLIGHT and is waiting for a certain condition to be met, as defined by your application. See also → Introducing Inflight.

3. transaction.rejected: This event is sent when a transaction is rejected because all of the conditions required to process it wasn’t met.

4. balance.monitor: This event is sent when a balance monitor has been triggered and the monitoring conditions set have been met. See also → Balance monitoring.

Each notification payload contains two main fields:

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Handling error notifications

In addition to transaction events, Blnk also allows you send error notifications to Slack via a specified webhook provided by your Slack workspace. This is very useful for monitoring and quickly addressing issues that may arise during transaction processing.

To learn how to get your Slack webhook URL, go to: Slack API: Sending messages using incoming webhooks.

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Configuring notifications in Blnk

To set up how you receive notifications from Blnk, you need to update your blnk.json configuration file. This file allows you to specify the webhook URLs that Blnk sends notifications to — both for your application and Slack.

If you do not have a blnk.json file, please create a new json file — it contains essential settings for running your Blnk server.

Next, copy & paste the configuration JSON into it. See also → Run Blnk server.

Update the notification object as follows:

• slack:
  • webhook_url: The webhook URL provided by your Slack workspace.
• webhook:
  • url: Your application’s webhook URL where Blnk sends transaction event notifications to.
  • headers: Optional headers that you may need to include in the notification request to authenticate the message. This can include authentication tokens or content type specifications.

Below is an example of a notifications configuration:

{
  "notification": {
    "slack": {
      "webhook_url": "https://hooks.slack.com/services/T00000000/B00000000/XXXXXXXXXXXXXXXXXXXXXXXX"
    },
    "webhook": {
      "url": "http://server:5001/webhooks",
      "headers": {
        "Content-Type": "application/json",
        "Authorization": "Bearer <your_auth_token>"
      }
    }
  }
}

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See also

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Need help?

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