Add capability add/drop option for creating and updating services

[matusnovak]

Recently the --cap-add option has been added to stack/service commands. Link to the PR: docker/cli#2687

It is done by adding CapabilityAdd and CapabilityDrop into the TaskTemplate -> ContainerSpec within the request body. See here: https://github.com/thaJeztah/cli/blob/master/cli/compose/convert/service.go#L153-L154

At the moment, there is no such option in docker-py when creating services -> https://docker-py.readthedocs.io/en/stable/services.html

[feliperuhland]

Hi @matusnovak

I opened a Pull Request for that feature #2809

[matusnovak]

Thank you @feliperuhland I will be very glad once that gets merged. I am closing this issue.