Support for manifests using docker experimental cli commands

[dims]

Re-proposing changes from #516 that were reverted in #620

[dims]

cc @mkumatag @dougm @tpepper

[dims]

/assign @calebamiles

[dims]

The environment variable will ensure that if config.json is over-written we still will have the experimental capability in the CLI

See docker/cli#1138 on where this env variable support was added

[mkumatag]

18.06.1~ce~3-0~ubuntu is already out, just see if you can use that version..

[dims]

@mkumatag we kinda tested the 18.06.0 bump yesterday so let's leave it alone unless 18.06.1 is absolutely necessary

[BenTheElder]

this same pinning is in place in test-infra for docker in docker building (we talked to releng about this) because we started flaking a ton on image pull around then. we've also not upgraded.. filing a bug for us to upgrade as well

[mkumatag]

I tested docker manifest --help command it worked after setting that environment variable

root@localhost:~# docker manifest --help
docker manifest is only supported on a Docker cli with experimental cli features enabled
root@localhost:~# export DOCKER_CLI_EXPERIMENTAL=enabled
root@localhost:~# docker manifest --help

Usage:    docker manifest COMMAND

Manage Docker image manifests and manifest lists

Commands:
  annotate    Add additional information to a local image manifest
  create      Create a local manifest list for annotating and pushing to a registry
  inspect     Display an image manifest, or manifest list
  push        Push a manifest list to a repository

Run 'docker manifest COMMAND --help' for more information on a command.
root@localhost:~#

[mkumatag]

/lgtm

[calebamiles]

/hold
until we decide how to move forward in a SIG Release meeting

[dougm]

Built + pushed the cloud builder image with this PR, currently running a mock build:

% git rev-parse HEAD
e4eef2277db5b12485c94715ce8380ead96a3c78
% gcloud --project kubernetes-release-test builds submit --config k8s-container.yaml
latest: digest: sha256:4503c04b0eeab2185d63d45503e9bec3cf582244d1deba300dc7ad7505184a9d size: 3256
DONE
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

ID                                    CREATE_TIME                DURATION  SOURCE                                                                                             IMAGES                                                      STATUS
5e95c99c-6b28-47d2-9488-b05901df3b6e  2018-09-08T00:07:34+00:00  6M6S      gs://kubernetes-release-test_cloudbuild/source/1536365253.43-87389752b5ea4aaf8be67a86880669dd.tgz  gcr.io/kubernetes-release-test/k8s-cloud-builder (+1 more)  SUCCESS

[dougm]

Running a mock build with @dims ' k/release master branch via:

modified   gcb/stage.yaml
@@ -9,7 +9,7 @@ steps:
 - name: gcr.io/cloud-builders/git
   args:
   - "clone"
-  - "https://github.com/kubernetes/release"
+  - "https://github.com/dims/release"
 
 - name: gcr.io/$PROJECT_ID/k8s-cloud-builder
   dir: release

The new Docker checks are passing:

Step #1: ================================================================================
Step #1: CHECK PREREQUISITES  (1/6)
Step #1: ================================================================================
Step #1: 
Step #1: Checking required system packages: OK
Step #1: Checking required PIP packages: OK
Step #1: Skipping security_layer::auth_check...
Step #1: Checking Docker version: OK
Step #1: Verifying Docker CLI Experimental status: OK
Step #1: Checking write access to registry gcr.io/kubernetes-release-test: OK
Step #1: Checking write access to registry k8s.gcr.io: OK
Step #1: Checking cloud project state: OK
Step #1: Checking write access to bucket kubernetes-release-gcb: OK
Step #1: [2018-Sep-08 01:06:00 UTC] check_prerequisites in 9s

[dougm]

Note that the initial beta.1 build before reverting these changes had failed the check:
Step #1: Verifying Docker CLI Experimental status

[calebamiles]

/hold cancel
per discussion in the SIG Release mailing list

[calebamiles]

/approve

[calebamiles]

/assign @dims

[dougm]

lgtm - I can "revert" the build image to the current master branch or wait for this PR to merge and rebuild/push then. Just let me know what you prefer @calebamiles @dims

[dims]

@dougm i don't have a preference either way. Since you are the only one who has the super powers :) i am ok with either call.

[dougm]

/lgtm

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: calebamiles, dims, dougm, mkumatag

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• OWNERS [calebamiles]

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