Jib should read the Docker environment variables and daemon.json

[briandealwis]

Jib should seed itself with Docker configuration when available.

Environment

The docker-provided inspectDockerImage tool supports the following environment variables:

• DOCKER_REGISTRY_AUTH_ENDPOINT, defaults to https://registry-1.docker.io
• DOCKER_REGISTRY_API_ENDPOINT, defaults to https://auth.docker.io

daemon.json

The Docker daemon.json file configures:

• insecure-registries a set of registries allowed to be HTTP-only
• registry-mirrors: a set of mirrors to consult, sometimes used to reference country-level mirrors like Docker's China Mirror.

The daemon.json file lives at:

• /etc/docker/daemon.json on Linux
• %ProgramData%\docker\config\daemon.json on Windows
• ~/.docker/daemon.json on macOS (not documented, but it's there)

[PavelGloba]

Since dockerhub introduced the pull limits, this closed issue is now relevant.
It should be covered by reading daemon.json, but the milestone for it is constantly changing. It would be great if registry-mirror feature could be prioritized.

[chanseokoh]

@PavelGloba as mentioned in #1396 (comment), you can simply point your base image to your registry mirror. Hence we don't see registry-mirrors as a high priority feature but basically something cool to have. UPDATE: wrong. --registry-mirrors must be supported by Jib: #1396 (comment)

Mind to explain to us why you'd like to have Jib follow the same workflow that the Docker daemon goes through regarding registry-mirrors?

[PavelGloba]

@chanseokoh Well, the reason is the same as why registry-mirrors exists in daemon.json
You can set it once in one place instead of pointing every image that you use to your mirror. That's not an issue if you have one project with one base image, but on a large scale it's becoming a problem.
Also, you can set up multiple mirrors there for failover.

[chanseokoh]

Reopened #1396 about the registry-mirror support.

[chanseokoh]

@PavelGloba to better support the users hitting the Docker Hub rate limiting, we implemented the registry mirror feature, which is now live with the Jib 2.8.0 release. Check out this FAQ to learn how to configure it.

[mpeddada1]

Closing issue as registry-mirror support is now available in the plugins and Jib CLI through a global config file (see README). Please re-open if this feature is still relevant.