How to trigger Slack notifications as a Validation Action¶

This guide will help you trigger Slack notifications as a Validation Action . It will allow you to send a Slack message including information about a Validation Result, including whether or not the Validation succeeded.

Prerequisites: This how-to guide assumes that you have already:

Configured a Slack app with the Webhook function enabled (See Additional Resources below for more information on setting up a new Slack app).
Obtained the Webhook address for your Slack app.
Identified the Slack channel that messages will be sent to.

Steps¶

Open uncommitted/config_variables.yml file and add validation_notification_slack_webhook variable by adding the following line:

validation_notification_slack_webhook: [address to web hook]

Open great_expectations.yml and add send_slack_notification_on_validation_result action to validation_operators. Make sure the following section exists in the great_expectations.yml file.

validation_operators:
    action_list_operator:
        # To learn how to configure sending Slack notifications during evaluation
        # (and other customizations), read: https://docs.greatexpectations.io/en/latest/reference/validation_operators/action_list_validation_operator.html
        class_name: ActionListValidationOperator
        action_list:
        #--------------------------------
        # here is what you will be adding
        #--------------------------------
        - name: send_slack_notification_on_validation_result # name can be set to any value
          action:
            class_name: SlackNotificationAction
            # put the actual webhook URL in the uncommitted/config_variables.yml file
            slack_webhook: ${validation_notification_slack_webhook}
            notify_on: all # possible values: "all", "failure", "success"
            notify_with: # optional list containing the DataDocs sites to include in the notification. Defaults to including links to all configured sites.
            renderer:
              module_name: great_expectations.render.renderer.slack_renderer
              class_name: SlackRenderer

Run your action_list_operator, to validate a batch of data and receive Slack notification on the success or failure of validation suite.

context.run_validation_operator('action_list_operator', assets_to_validate=batch, run_name="slack_test")
If successful, you should receive a Slack message that looks like this:

Additional notes¶

If your great_expectations.yml contains multiple configurations for Data Docs sites, all of them will be included in the Slack notification by default. If you would like to be more specific, you can configure the notify_with variable in your great_expectations.yml.
The following example will configure the Slack message to include links Data Docs at local_site and s3_site.

# Example data_docs_sites configuration
data_docs_sites:
  local_site:
    class_name: SiteBuilder
    show_how_to_buttons: true
    store_backend:
      class_name: TupleFilesystemStoreBackend
      base_directory: uncommitted/data_docs/local_site/
    site_index_builder:
      class_name: DefaultSiteIndexBuilder
  s3_site:  # this is a user-selected name - you may select your own
    class_name: SiteBuilder
    store_backend:
      class_name: TupleS3StoreBackend
      bucket: data-docs.my_org  # UPDATE the bucket name here to match the bucket you configured above.
    site_index_builder:
      class_name: DefaultSiteIndexBuilder
      show_cta_footer: true

validation_operators:
    action_list_operator:
    ...
    - name: send_slack_notification_on_validation_result # name can be set to any value
          action:
            class_name: SlackNotificationAction
            # put the actual webhook URL in the uncommitted/config_variables.yml file
            slack_webhook: ${validation_notification_slack_webhook}
            notify_on: all # possible values: "all", "failure", "success"
            #--------------------------------
            # This is what was configured
            #--------------------------------
            notify_with:
              - local_site
              - s3_site
            renderer:
              module_name: great_expectations.render.renderer.slack_renderer
              class_name: SlackRenderer

Additional resources¶

Instructions on how to set up a Slack app with webhook can be found in the documentation for the Slack API