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Image Builder

We would like to use Image Builder to compose bootable images that would contain upstream code that anyone can boot and play with it, especially contributors.

Packit needs to work with Image Builder API in order to start those image builds.

Image Builder API

@ondrejbudai created a great intro blog post how to use the API. Please read it before continuing reading.


  1. Create a token here and generate an access token from it to use with Image Builder API
  2. API docs:
  3. Web UI:
  4. Image Builder service docs
  5. The team has their own gchat room, guess the name :)


The API works well, but the experience wasn't perfect. Be aware of these:

  1. There are no build logs and there is no plan right now to have them.
  2. In case of failure, there is only a single error message provided that can be confusing (see Jira tickets linked from to HMSIB)
  3. No callbacks, one needs to poll to find out about the completion about an image build


We have a PoC in mind (Installer team needs bootable images off PRs to see the change in action). I started a simple python script that submits an image build and waits for it to finish. The image installs cockpit on RHEL 9 from cockpit's releases Copr project.

Once the image is built, there is a link in the webui to launch an AWS EC2 instance and play with it. Neat!


Set the offline token via REDHAT_API_OFFLINE_TOKEN env var and run the "" script.

Next steps

The integration is pretty straightforward:

  1. Create a new job: "vm-image-build"

  2. Implement a handler for it (trigger = successful Copr build + explicit /packit command)

  3. Wait for the build to finish: babysit/polling/celery

  4. Auth - create a 'service' account for Packit on

    • Attach employee SKU to it
    • Create a refresh token & store it in bitwarden
    • Inform Image Builder team about this user so they are aware of it (maybe increase quota)
    • We need to figure out how images will be shared with users (they can provide their AWS/GCP/Azure account ID so Image Builder can share the uploaded image with it)
  5. Once the build is done, put a comment in a PR that the build is done and provide steps how to access it and possibly launch it