Webhooks

A webhook is a POST request sent to a URL that you define in Docker Hub or another registry. Use webhooks to trigger an action or a service in response to a repository push event.

{% hint style="info" %} Webhooks are only available on non-Edge environments (environments running Portainer Server or Portainer Agent, not the Portainer Edge Agent). This is because the tunnel to the Portainer Edge Agent is only opened on-demand, and therefore would mean there is no way to expose a webhook permanently. {% endhint %}

Enabling a service webhook

From the menu select Services then select the service that you want to configure the webhook for.

In the Service details screen toggle the Service webhook option on. When the URL appears, click Copy link. This URL will be used to configure the webhook in your chosen registry.

This example shows how to trigger the webhook using redeploy:

<form action="https://portainer:9443/api/webhooks/638e6967-ef77-4906-8af8-236800621360" method="post">
  Redeploy with latest image of same tag <input type="submit" />
</form>

This example shows how to trigger the webhook using update service image with a different tag:

<form action="https://portainer:9443/api/webhooks/638e6967-ef77-4906-8af8-236800621360?tag=latest" method="post">
  Update Service image with different tag <input type="submit" />
</form>

Using environment variables with webhooks

When triggering a webhook, environment variables can be passed through the endpoint and referenced within services' compose files.

{% hint style="info" %} This functionality is only available in Portainer Business Edition. {% endhint %}

To specify an environment variable on a webhook, add it as a variable to the URL. For example, to pass a SERVICE_TAG variable with the value development:

https://portainer:9443/api/webhooks/1d251d96-fb34-4172-a0a1-d0655467b897?SERVICE_TAG=development

To reference the SERVICE_TAG variable in your compose file with a fallback to the value stable:

services:
  my-service:
    image: repository/image:${SERVICE_TAG:-stable}

Configuring the webhook in Docker Hub

To finish the configuration, refer to Docker's own documentation.