validate command doesn't allow specifying a channel

[Daniel Manrique]

Currently, validations can only be issued to gate snaps which have a release on the stable channel _at the moment of creating the validation_.

This is because `snapcraft validate` uses the details API to get the details from the stable channel only, and it doesn’t allow specifying another channel to get the gated snap’s details. However, once the validation is in place, validations are channel-agnostic because they operate at the revision level.

        $ snapcraft status gated-1
        Track Arch Channel Version Revision
        Latest amd64 stable - -
                     Candidate - -
                     beta - -
                     edge 2018-05-30-04 3

        $ snapcraft validate gating-1 gated-1=3
        Getting details for gated-1
        Snap 'gated-1' was not found in the 'stable' channel.

A way to validate a snap that's not published to stable (maybe by specifying another channel) would be useful.

Specifying a revision would also be good but since the person issuing the validation may not necessarily be a developer or collaborator for the gated snap (core is a commonly-gated snap and very few people are collabs for core :) this is likely to not be useful most of the time.

[Natalia Bidart (nataliabidart)]

Somehow related to bug LP: #1902913

[Kyle Nitzsche (knitzsche)]

Does this mean that the specified gated snap revision must be available on *any* arbitrary "stable" channel, regardless of track and branch (for example 20/stable, latest/stable, 18/stable/somebranch) in order to issue the validation assertion?

[Sergio Schvezov (sergiusens)]

Kyle, if you have the snap-id you can use that instead.