Revert "imageDigest only for ecr"

[sparrc]

This reverts commit af54b2f.

This would address aws/containers-roadmap#1640

Summary

It was originally decided to supply image digests only for ECR because the image digests we supply do not match the dockerhub UI. This is because the dockerhub UI only shows individual "manifest" image digests for each particular image variant. ECR, on the other hand, displays the "index" digest, which is a single digest shared across all variants of a single image. Somewhat confusingly, the docker image inspect command shows the "index" image digest too.

What this means is that docker image pull and docker image inspect show a different image digest than the dockerhub UI. This is confusing for docker customers and fixing this is one of the most-upvoted feature requests for dockerhub: docker/hub-feedback#1925

Our solution to customer confusion to just simply omit the digest for non-ECR repos was probably not correct. Customers want image digests for all their images. If customers are confused why the docker "index" digest that they see in ecs.DescribeTasks does not match the "manifest" digest they see in dockerhub, then this is a documentation and education issue, not a code issue.

Testing

tested calling ecs.DescribeTasks before and after this change.

Before the change, can see imageDigest field only for private ECR repos:

private ECR (before change):

  "image": "XXXX.dkr.ecr.us-west-2.amazonaws.com/XXXX:XXXX",
  "imageDigest": "sha256:eab773b3c3916e73c19232cc854233a17b332754733f07dc75ccb6229a19b766",

public ECR (before change):

  "image": "public.ecr.aws/docker/library/busybox:latest",

dockerhub (before change):

  "image": "busybox:latest",

After this PR, can see imageDigest field for all images:

private ECR (after change):

  "image": "XXXX.dkr.ecr.us-west-2.amazonaws.com/XXXX:XXXX",
  "imageDigest": "sha256:eab773b3c3916e73c19232cc854233a17b332754733f07dc75ccb6229a19b766",

public ECR (after change):

  "image": "public.ecr.aws/docker/library/busybox:latest",
  "imageDigest": "sha256:7b3ccabffc97de872a30dfd234fd972a66d247c8cfc69b0550f276481852627c",

dockerhub (after change):

  "image": "busybox:latest",
  "imageDigest": "sha256:7b3ccabffc97de872a30dfd234fd972a66d247c8cfc69b0550f276481852627c",

Description for the changelog

Enhancement: Provide imageDigest for images from all container repositories

Licensing

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[holyspectral]

Any news on this? Would love to see image digest on other type of registries.

[sparrc]

Any news on this? Would love to see image digest on other type of registries.

testing and getting it ready now, should be merged in a matter of weeks

[holyspectral]

So happy to see this PR is merged! I guess it's out of this repo's scope, but by any chance this change will also be in Fargate container agent?