remove docker repository on remote docker registry - docker

Question

Given a docker registry managing multiple docker repositories, how do I delete one of the repositores?
Given docker repositories repo1 and repo2.
$ curl -X GET localhost:5000/v2/_catalog
{"repositories":["repo1", "repo2"]}
I want to remove repository repo1 so _catalog does not list repo1, like
$ curl -X GET localhost:5000/v2/_catalog
{"repositories":["repo2"]}
Currently, repository repo1 only has the default "latest" image tag
$ curl -X GET localhost:5000/v2/repo1/tags/list
{"name":"repo1","tags":["latest"]}
(Maybe that affects being able to delete repo1?)
I have tried...
The following commands returned 404 page not found:
$ curl -X DELETE localhost:5000/v1/repositories/repo1
$ curl -X DELETE localhost:5000/v2/repositories/repo1
$ curl -X DELETE localhost:5000/v2/repo1
And the following returned {"errors":[{"code":"UNSUPPORTED","message":"The operation is unsupported."}]}
$ curl -X DELETE localhost:5000/v2/repo1/manifests/latest
Using versions
The remote docker-registry is registry/2.0
curl -vX GET localhost:5000/v2/
< HTTP/1.1 200 OK
...
< Docker-Distribution-Api-Version: registry/2.0
...
and
$ /bin/registry github.com/docker/distribution v2.4.1

Answer 1

by enabling DELETE API you're only able to delete the TAG not the whole repository from v2/_catalog.
in order to do this, you should:
1. enable DELETE API:
1.1 by config.yml : storage.delete.enabled:true
1.2 by env: -e REGISTRY_STORAGE_DELETE_ENABLED=true
2. get the tag reference via GET /v2/<name>/manifests/<tag>
(don't forget to have Header Accept: application/vnd.docker.distribution.manifest.v2+json).
in response headers, you have docker-content-digest: <sha256:xxx>
3. send DELETE /v2/<name>/manifests/<sha256:xxx>
4. run garbage collector: bin/registry garbage-collect /etc/docker/registry/config.yml
5. remove files: rm -r /var/lib/registry/docker/registry/v2/repositories/<name>/<tag>
finally: now you can see
curl -X GET localhost:5000/v2/_catalog
{"repositories":["repo2", "repo3"]}
ps.
consequences of 5: https://github.com/docker/distribution/issues/2983#issuecomment-530251232

Answer 2

There is no API to delete a repository. You need to delete individual tags or manifests within the repository. And until OCI's distribution-spec, there wasn't even an API to delete tags, you need to delete image manifests by digest, which deletes all tags pointing to that same digest.
To delete manifests, first ensure that you have enabled deletion according to this documentation before attempting anything. In your configuration of the registry, you would add the following section:
delete:
enabled: true
That can also be set by starting your registry container with the REGISTRY_STORAGE_DELETE_ENABLED=true environment variable specified.
Then you can call the manifest delete API:
curl -X DELETE \
-s "https://registry.example.org/v2/${repo}/manifests/${sha}"
If you want a wrapper around this to handle auth, and even support tag deletion, see regclient's regctl CLI that I've written. Google's crane and RedHat's skopeo may also provide this.
Once the manifests are deleted, you still need to clean the other items the manifest pointed to with a garbage collection (this needs to be done when no writes are occurring):
docker exec registry /bin/registry garbage-collect /etc/docker/registry/config.yml --delete-untagged
That said, you'll still reach the point where the repository itself is not removed. You can delete the entire directory from the filesystem of the registry. But I would recommend getting support for this implemented from the project. See this issue for more details on getting the capability added to the official registry image.