Add pull-through cache for Docker Hub images

[baixiac]

No description provided.

[keyvaann]

Thanks! I'll have a look into this

[keyvaann]

Thanks! Would it be good to add configuration for Repository creation templates as well? Using that we can define Repository lifecycle policies to delete older images and reduce ECR costs.

[baixiac]

Using that we can define Repository lifecycle policies to delete older images and reduce ECR costs.

Had that at the back of my mind. Since PTC repos do not support lifecycle policies, I see two options here:

1. Wait for AWS to push out the feature (it sounds a very useful one other users may have already cried for);
2. Create a Lambda function, triggered periodically to check the last usage time and evict least used images (this adds complexity to the template, comparable to the traditional cache management)

Any thoughts or more options?