Add support for the registry-mirror docker option

[kasimon]

Is your feature request related to a problem? Please describe. Our docker daemons run with the registry-mirror=<internal-docker-proxy> setting set, as our systems cannot access the internet directly. We have configured sonatype nexus as a pass through cache for this. But we have not been able to enable this option for watchtower, resulting in watchtower trying to connect directly to external registries and failing.

Describe the solution you'd like Support the registry-mirror setting in config.json (we have mounted /etc/docker/daemon.json to /config.json) or provide an option WATCHTOWER_DOCKER_REGISTRY_MIRROR=... to watchtower.

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[brechsteiner]

+1

[1983shake]

+1

[Kagee]

Does watchtower pull the images on it's own, not through docker? We also require this option, and it is configured and works just fine when using the docker cli directly on host we run watchtower on, but when the watchtower container tries to update it claims

time="2024-07-24T14:26:43Z" level=warning msg="Could not do a head request for \"containrrr/watchtower:latest\", falling back to regular pull." container=/watchtower image="containrrr/watchtower:latest"
time="2024-07-24T14:26:43Z" level=warning msg="Reason: Get \"https://index.docker.io/v2/\": dial tcp: lookup index.docker.io: i/o timeout" container=/watchtower image="containrrr/watchtower:latest"
t

even tough i can see in the docker mirror logs that a HEAD request was issued and a response was sent?

[kasimon]

AFAIK watchtower doesn't pull images, but checks the registry for new images directly over the registry api.

[uwang]

+1

[DavidZhang73]

+1