ubuntu-image needs to provide a manifest for the contents of an image

$ ubuntu-image -w /tmp/wd pc-amd64.assertion
$ ls /tmp/wd/root/system-data/var/lib/snapd/snaps/
core_1636.snap pc-kernel_60.snap

So that seems like the information you're asking for. I guess a file listing of that directory would be the manifest you want, right? Should we just add a -m/--manifest argument which names a file into which we would write these snap file names?

On Thu, Apr 06, 2017 at 07:26:46PM -0000, Barry Warsaw wrote:
> $ ubuntu-image -w /tmp/wd pc-amd64.assertion
> $ ls /tmp/wd/root/system-data/var/lib/snapd/snaps/
> core_1636.snap pc-kernel_60.snap

> So that seems like the information you're asking for. I guess a file
> listing of that directory would be the manifest you want, right?

That would suffice. It might be nice to do some basic transformations here,
to make the manifest tabular - à la
<http://cdimage.ubuntu.com/ubuntu-base/daily/current/zesty-base-amd64.manifest>.

> Should we just add a -m/--manifest argument which names a file into which
> we would write these snap file names?

I think I would prefer it be written by default to the output dir under a
fixed name (and if not using -O, to write it out as <foo>.manifest alongside
<foo>.img). It's a cheap enough thing to create, and common enough to want,
that I think we should just do it as the sensible default thing instead of
requiring the user to ask for it. If they don't want it, it's a pretty
cheap file to clean up.

On Apr 07, 2017, at 12:37 AM, Steve Langasek wrote:

>That would suffice. It might be nice to do some basic transformations here,
>to make the manifest tabular - à la

Is this file primarily for human or machine consumption?

>I think I would prefer it be written by default to the output dir under a
>fixed name (and if not using -O, to write it out as <foo>.manifest alongside
><foo>.img). It's a cheap enough thing to create, and common enough to want,
>that I think we should just do it as the sensible default thing instead of
>requiring the user to ask for it. If they don't want it, it's a pretty
>cheap file to clean up.

We can do that. Let's be careful though because the file won't contain a
complete manifest of the image, but only a manifest of the snaps. .svm seems
to be unused-ish (snap version manifest).

https://en.wikipedia.org/wiki/List_of_filename_extensions_(S%E2%80%93Z)#S

% mimetype foo.svm
foo.svm:

Something else to consider: since there's only one rootfs defined, and the snaps will be in that partition, maybe we should just write a single file called 'snap.manifest'

And I suppose it should look in rootfs/system-data/var/lib/snapd/seeds (which looks like a superset of var/lib/snapd/snaps)?

How about something to this effect?

$ ubuntu-image -O /tmp/out pc-amd64-model.assertion
$ ls /tmp/out
pc.img seed.manifest snaps.manifest
$ cat /tmp/out/seed.manifest
core 1640
pc 19
pc-kernel 60
$ cat /tmp/out/snaps.manifest
core 1640
pc-kernel 60

Let me try to pick it up this week.

On Fri, Apr 07, 2017 at 01:40:10PM -0000, Barry Warsaw wrote:
> On Apr 07, 2017, at 12:37 AM, Steve Langasek wrote:

> >That would suffice. It might be nice to do some basic transformations here,
> >to make the manifest tabular - à la

> Is this file primarily for human or machine consumption?

Human. It would e.g. be published alongside images on cdimage.ubuntu.com,
so we can easily inspect contents of a given image.

On Fri, Apr 07, 2017 at 09:57:16PM -0000, Barry Warsaw wrote:
> How about something to this effect?

> $ ubuntu-image -O /tmp/out pc-amd64-model.assertion
> $ ls /tmp/out
> pc.img seed.manifest snaps.manifest
> $ cat /tmp/out/seed.manifest
> core 1640
> pc 19
> pc-kernel 60
> $ cat /tmp/out/snaps.manifest
> core 1640
> pc-kernel 60

That seems pretty reasonable to me.