Provide the size of the disk image, along with the checksum and url

[afbjorklund]

Description

I know that one can ask the server, but maybe it is down or slow.

When we automate the checksumming ("digest"), we could have it populate the byte size as well ?

images:
# Try to use release-yyyyMMdd image if available. Note that release-yyyyMMdd will be removed after several months.
- location: "https://cloud-images.ubuntu.com/releases/22.10/release-20230413/ubuntu-22.10-server-cloudimg-amd64.img"
  arch: "x86_64"
  size: 762445824
  digest: "sha256:d46438111d7a6dfcdfb2e1fb76762a79d56f09dc308cc9ab2300effc0078fd5b"
- location: "https://cloud-images.ubuntu.com/releases/22.10/release-20230413/ubuntu-22.10-server-cloudimg-arm64.img"
  arch: "aarch64"
  size: 739573760
  digest: "sha256:e1865c2ebc531600ae6012d86fa2dae5846e7801cdcdbcf90d9c830218ef4ae9"
# Fallback to the latest release image.
# Hint: run `limactl prune` to invalidate the cache
- location: "https://cloud-images.ubuntu.com/releases/22.10/release/ubuntu-22.10-server-cloudimg-amd64.img"
  arch: "x86_64"
- location: "https://cloud-images.ubuntu.com/releases/22.10/release/ubuntu-22.10-server-cloudimg-arm64.img"
  arch: "aarch64"

A disk size of "0" would just mean that we don't know, before contacting (or that the image is generic)

• Automation for updating templates #1347

[afbjorklund]

The reason for this was the question of "which template has the bigger images, ubuntu or debian"

[AkihiroSuda]

Any reason not to just use comment lines?

[afbjorklund]

Wouldn't that make the parsing harder ? I'm imaging some kind of tool or visualization, similar to what we currently do for du

So far the workaround was more in the lines of curl --head, once you figure out the URL to use for the template that you want.

[afbjorklund]

Like if you want to use some parsing construct, avoid hitting the remote server for known information....

limactl info | yq '.templates[] | select(.name == "debian") | .location' | xargs yq .images

[AkihiroSuda]

I'm fine to add the size field, but I expect it to happen after this:

• Automation for updating templates #1347

Otherwise maintaining the templates will be even much harder.

[afbjorklund]

I'm not sure how important disk size really is, these days.

If one really wanted to complicate things, it could even record the uncompressed* size (like apt shows you)
But in general, I think you want to have plenty of disk space (10G+) available when running virtual machines.

* this would only make sense for compressed images