pubsys: minor cleanup

[tjkirch]

commit 5b684ea3be5b84cd1aeffda5e274a2d9ee6a2156
Author: Tom Kirchner <tjk@amazon.com>
Date:   Sun Aug 23 17:16:09 2020 -0700

    pubsys: wait for AMIs to be available before granting access

    Without a wait, if you use publish_ami right after registering/copying AMIs,
    describe images responses can include partial information that doesn't include
    snapshot IDs.

commit afe9526e7ee415ac169bcdf4a3e055d59a7ddf87
Author: Tom Kirchner <tjk@amazon.com>
Date:   Sun Aug 23 17:35:06 2020 -0700

    pubsys: print waiting message only if we're going to sleep

    If the AMI is found on the first attempt, the success message is enough.

commit 08b31055ab117d03a252287311dc95ce8b3d80e5
Author: Tom Kirchner <tjk@amazon.com>
Date:   Sun Aug 23 17:04:21 2020 -0700

    pubsys: increase log level inside AMI registration process

    Waiting for snapshots is the longest part of AMI registration and there wasn't
    much explanation of what was happening, so this bumps a couple debug messages
    up to info level.

commit 6f60d7a2267491f313fdbf8769b772d487558d76
Author: Tom Kirchner <tjk@amazon.com>
Date:   Sun Aug 23 16:57:37 2020 -0700

    pubsys: rename client variable to reduce confusion

    It's too easy to use "ec2_client" by accident when you need a regional client,
    when this is actually a client just for the base region.

commit 996385ce19454653f037f81e35983f9012924610
Author: Tom Kirchner <tjk@amazon.com>
Date:   Sun Aug 23 16:55:21 2020 -0700

    pubsys: fix region name in error message

A few small bug fixes and a performance improvement, now that the blockers are out of the way.

Testing done:

• Ran an ami / ami-public / ami-private cycle successfully; before, if you ran ami-public immediately after ami you could get a failure based on partial describe-images responses not having snapshot IDs.
• Ran an ami-public / ami-private cycle with AMIs that already existed and saw the waits finish immediately.
• Saw the improved logging, for example:

00:48:25 [INFO] Registering 'bottlerocket-aws-k8s-1.17-x86_64-v0.5.0-5b684ea3' in us-west-2
00:50:17 [INFO] Waiting for root and data snapshots to become available in us-west-2
00:50:26 [INFO] Making register image call in us-west-2
00:50:26 [INFO] Registered AMI 'bottlerocket-aws-k8s-1.17-x86_64-v0.5.0-5b684ea3' in us-west-2: ami-12345

and:

00:56:07 [INFO] Waiting for AMIs to be available...
00:56:07 [INFO] Found ami-23456 available in us-west-1
...
00:56:11 [INFO] Updating snapshot permissions - making private

Terms of contribution:

By submitting this pull request, I agree that this contribution is dual-licensed under the terms of both the Apache License, version 2.0, and the MIT license.

[zmrow]

🖖

[tjkirch]

^ just a rebase on develop.