Minimal image sizes aren't consistent

[ondrejbudai]

Minimal images are currently derived from the default ones, see:

cockpit-composer/components/Wizard/CreateImageUpload.js

Line 246 in 0201d2d

minImageSize: defaultImageSize,

Default image sizes are basically hardcoded in cockpit-composer:

cockpit-composer/components/Wizard/CreateImageUpload.js

Lines 295 to 302 in 0201d2d

	getDefaultImageSize(imageType) {
	if (imageType === "ami") {
	return 6;
	}
	if (imageType === undefined) {
	return null;
	}
	return 2;

However, they definitely don't correspond to the default sizes in osbuild-composer:

Image type	RHEL 8.4	Fedora 33
ami	6	6
qcow2	10	2
openstack	4	2
vhd	4	2
vmdk	4	2

I wonder if should add a route to the Weldr API to return these default sizes and then load them in cockpit-composer. That shouldn't be super-hard. Thoughts? @jkozol @teg @bcl ?

[teg]

Maybe make this part of the filesystem work? Or change this in the UI to say "minimal size", and then accept that composer will round up? Default it to 0 in the UI.

[bcl]

I wonder if should add a route to the Weldr API to return these default sizes

The data returned from /compose/types seems like the natural place to add them (using api/v1 of course). It looks like those numbers come from distro.ImageType.Size() so that should be fairly easy to add.