Prune build cache

The Prune build cache action removes the Docker build cache from a Portainer endpoint to free up disk space. By default, all unused build cache is removed. You can limit the cleanup to dangling build cache, or to build cache that has not been used for a certain time.

Only administrators can use this action.

Using this action from the user interface

If you prefer building automations and scripts visually, Home Assistant walks you through this action step by step. You pick what to target, tweak a few options, and save. No YAML knowledge required.

To prune the build cache from an automation or a script:

1. Go to Settings > Automations & scenes.
2. Open an existing automation or script, or select Create to start a new one.
3. If you’re setting up a new automation, add a trigger in the When section. Scripts don’t need a trigger.
4. In the Then do section, select Add action.
5. From the search box, search for and select Portainer: Prune build cache.
6. Select the Endpoint to prune the build cache on.
7. Optionally, turn off All to only prune dangling build cache, and set how long the build cache must have been unused.
8. Select Save.

This action does not support targets. In the UI, you select the endpoint through the Endpoint field instead of choosing an area, device, entity, or label.

Options in the UI

Using this action in YAML

If you work directly in YAML, or you want to know exactly what Home Assistant does under the hood, this section has the technical reference. It lists the field names you use in YAML, their types, and which ones are required. For how an automation or a script is built in YAML, refer to Automations in YAML and Scripts.

In YAML, refer to this action as portainer.prune_build_cache:

action: portainer.prune_build_cache
data:
  device_id: a1b2c3d4e5f6a1b2c3d4e5f6a1b2c3d4
  all: false
  until:
    hours: 24

Options in YAML

Try it yourself

Ready to test this? Open Settings > Tools > Actions, search for this action, fill in the fields, and select Perform action. You see what happens on your actual entitiesAn entity represents a sensor, actor, or function in Home Assistant. Entities are used to monitor physical properties or to control other entities. An entity is usually part of a device or a service. [Learn more] without writing a line of YAML.

More examples

Real scenarios where this action shows up in automations and scripts. Copy any example and adapt it to your setup. In the visual editor, select the UI options listed in the example or paste the YAML code.

Automation: clean up the build cache every week

This automation prunes build cache that has not been used for a week, so images you build regularly still build quickly.

• Trigger: A scheduled time
• Action: Portainer: Prune build cache

alias: "Weekly Portainer build cache cleanup"
triggers:
  - trigger: time
    at: "03:00:00"
conditions:
  - condition: time
    weekday:
      - sun
actions:
  - action: portainer.prune_build_cache
    data:
      device_id: a1b2c3d4e5f6a1b2c3d4e5f6a1b2c3d4
      until:
        hours: 168

Still stuck?

To test the action on its own, run it in the automation editor with Run action, and check the message that it shows. To see what the action did when the automation ran, open the trace of that run. For details, refer to Testing automations. For common problems and their solutions, refer to Troubleshooting automations.

If that doesn’t help, the Home Assistant community is quick to help: join Discord for real-time chat, post on the community forum with the action you’re calling and what you expected to happen, or share on our subreddit /r/homeassistant.

Related actions

Explore related actions:

• Prune unused images: Removes unused images from a Portainer endpoint.