Builds are tagged upaas-<app>:<short hash>, git's own short form of
the commit checked out, instead of the deployment number.
A redeploy of a commit gives the tag to the new image. The cleanup
after a deploy now also finds the app's untagged images among those
its deployments recorded, and removes them by ID once the app neither
runs them nor would roll back to them. It keeps every image any app
uses, since apps that build the same commit can share one.
The clone reads the commits from git's output after removing Docker's
log headers, which had hidden the COMMIT: line; commit_sha is now
saved on update so manual deploys keep the commit they recorded.
Model: opus-5-5
Every deploy built and tagged a new image and nothing removed the old ones, so disk use grew with each push. After a successful deploy, upaas now removes the app's old `upaas-<app>:<N>` tags by name, without force, keeping the current image and the previous one that rollback starts. Docker deletes an image only when no other tag or container still uses it, so an image shared with another app stays. A failed removal is a warning in the deployment log, not a failed deploy. The post-deploy step is one function, tested against a fake Docker API.
Judgement call: untagged images from other stages of a multi-stage build stay; they are the build cache.
On the first deploy after upgrading, all older images of that app are removed at once.
Model: opus-5-5
clawbot