Trigger Deployments when Pipelines Complete in NextGen

Trigger deployments or a pipeline after the completion of another pipeline

This section describes how to trigger deployments or a pipeline after the completion of another pipeline.

Problem Statement

How can I trigger deployments or a pipeline after the completion of another pipeline?

Resolution

You can trigger Harness Pipeline deployments when specific Harness Pipelines complete their deployments.

For example, you might create a Pipeline to test a deployment in one environment. When it completes its deployment, a Trigger executes a second Pipeline to deploy to your stage environment.

The solution involves automating the triggering of a pipeline upon the successful completion of another pipeline by using custom triggers and webhooks. Here's a breakdown:

1. Create a Custom Trigger in the Target Pipeline:

• Target Pipeline: This is the pipeline that you want to start automatically after the completion of another pipeline (the source pipeline).

• Custom Trigger: A custom trigger is set up in the target pipeline, which listens for specific events (like a webhook call) to start the pipeline. This trigger can be configured to start the pipeline when it receives a specific request or notification.

• Custom Webhook Trigger https://developer.harness.io/docs/platform/triggers/custom-trigger-passing-data

2. Add a Webhook Notification in the Source Pipeline:

• Source Pipeline: This is the pipeline that, once it finishes, should trigger the target pipeline.

• Webhook Notification: A webhook is a way for an application to send real-time data to other applications. In this case, when the source pipeline finishes, it sends a webhook notification.

• Passing the Custom Trigger URL: The webhook notification includes the URL of the custom trigger created in the target pipeline. This URL is the endpoint that the webhook will hit to trigger the target pipeline.

• Passing Token (if mandatory): Some systems require authentication for security reasons. If the custom trigger requires authentication, you would pass a token as part of the request header in the webhook. This token is often stored as a secret to keep it secure.

• Webhook Notifications: https://developer.harness.io/docs/platform/notifications/notifications/configure-notifications#configure-pipeline-notifications

Workflow Summary:

1. Setup the Custom Trigger: In the target pipeline, create a custom trigger that listens for a webhook event.

2. Configure the Source Pipeline: Add a webhook notification to the source pipeline that will be triggered upon its completion.

3. Trigger the Target Pipeline: When the source pipeline finishes, it sends a webhook request to the custom trigger URL of the target pipeline. If required, it includes a secret token for authentication.

4. Target Pipeline Starts: The target pipeline starts executing based on the custom trigger's configuration.

This setup ensures that the target pipeline automatically runs after the successful completion of the source pipeline, creating a seamless automation flow between the two pipelines.