snap download can't find snaps from a branded store

[Tony Espy]

If I try to download a gadget or kernel snap and its supporting assertions using 'snap download' on a Dell Gateway 5000 running Ubuntu Core 16 (snapd == 2.21), the command returns:

Fetching snap "stlouis"
error: cannot find snap "stlouis": snap not found

Note, the kernel and gadget snaps live in a branded store. This doesn't seem to be an issue for 'snap install' or 'snap refresh'.

The same error happened for another snap in related branded store that's only been published to edge. Even if I specify --edge on the download command, this snap isn't found either, yet I can install it using 'snap install --edge'.

[Oliver Grawert (ogra)]

there were connectivity issues with the store yesterday, could that be related ? (did the other snaps download ?)

[Simon Fels (morphis)]

Reason for this is that "snap downlaod" doesn't configure any specific store or authentication parameters for its access to the store at https://github.com/snapcore/snapd/blob/master/cmd/snap/cmd_download.go#L117

Both are required to download snap from private stores.

[Simon Fels (morphis)]

there is still a workaround I think, by doing a snap install on an existing system and fetching relevant things from /var/lib/snapd manually, not nice but a workaround

[Simon Fels (morphis)]

I've pushed a PR to allow the user specifying a store ID for the snap download command via a --store-id=<ID> argument. See https://github.com/snapcore/snapd/pull/2818

This doesn't yet respect authentication.

[Tony Espy (awe)]

@Michael

As Simon pointed out in comment #4, his workaround will only work if the private store hasn't enabled authentication. I think long term, 'snap download' needs to be re-worked to use snapd directly for downloads, which would allow proper store authentication to occur.

[Zygmunt Krynicki (zyga)]

I believe there's ongoing work on allowing "snap download" to take advantage of snapd's cache and configuration, including the branded store.

I can find the following pull request that is related to this problem

https://github.com/snapcore/snapd/pull/7624

I'm marking it as in progress and assigned to mvo.

[Zygmunt Krynicki (zyga)]

This bug is still in progress. I believe it has lower priority than before due to the current focus on various ubuntu core 20 topics.

[Zygmunt Krynicki (zyga)]

The updated URL is https://github.com/snapcore/snapd/pull/7977 but it is closed.