Stream metadata

Metadata about Fedora CoreOS is available in a custom JSON format, called "stream metadata". For maintaining automation, it is expected that you will interact with this stream metadata.

The format is stable, and intended to be relatively self-documenting. There is not yet a JSON schema. However, in most web browsers, navigating to the URL will render the JSON in an easy-to-read form.

Canonical URL

The URL for the stable stream is: https://builds.coreos.fedoraproject.org/streams/stable.json You can similarly replace stable here with other available Update Streams.

Using coreos-installer to download

The coreos-installer tool has built-in support for fetching artifacts:

STREAM='stable'
coreos-installer download --decompress -s $STREAM -p openstack -f qcow2.xz

Using coreos/stream-metadata-go

There is an official coreos/stream-metadata-go library for software written in the Go programming language. The README.md file in that repository contains a link to example code.

Example: Script ec2 CLI

Fetch the latest x86_64 AMI in us-west-1 and use it to launch an instance:

$ AMI=$(curl -sSL https://builds.coreos.fedoraproject.org/streams/stable.json | jq -r '.architectures.x86_64.images.aws.regions["us-west-1"].image')
$ echo $AMI
ami-021238084bf8c95ff
$ aws ec2 run-instances --region us-west-1 --image-id "${AMI}" ...