util.sanitize_source truncates squashfs source types

[Chad Smith]

When source contains the prefix squashfs:something util.santize_source trucates the uri returned to a single character

python3 -c 'from curtin.util import sanitize_source; print(sanitize_source("squashfs:mine"))'
{'type': 'fsimage', 'uri': 'm'}

[Ryan Harper (raharper)]

Thanks for filing the bug. The 'squashfs:' prefix is currently unsupported.

The correct way to specify a squashfs source is via fsimage:// or http://

For example:

>>> util.sanitize_source("fsimage:///nfsmount/ubuntu.squash")
{'type': 'fsimage', 'uri': '///nfsmount/ubuntu.squash'}

>>> util.sanitize_source("http://cloud.images.ubuntu.com/bionic/test.squash")
{'type': 'fsimage', 'uri': 'http://cloud.images.ubuntu.com/bionic/test.squash'}

That said, we should fix the bug and add the prefix and suffix feature to
the documentation.

[Server Team CI bot (server-team-bot)]

This bug is fixed with commit 95197ff5 to curtin on branch master.
To view that commit see the following URL:
https://git.launchpad.net/curtin/commit/?id=95197ff5