Allowing for docker images not based on binder-base

[nthiery]

Dear Binder devs,

SageMath is an open source Python based software for computational mathematics. We are planning to build a docker image that could be used by our users to easily deploy their favorite SageMath notebooks thanks to the great mybinder service.

We already have docker images for SageMath, which include a Jupyter server. Would there be a chance to use them (or some derivatives), rather than recreating some new docker image deriving from binder-base?

Put otherwise:

• Is there an API describing what features a docker image should provide to be binder-compatible?

• Does binder-build explicitly require the docker image to derive from binder-base (maybe as a security measure)? Could this restriction be lifted?

• I did not find the DockerFile for binder-base; is it available somewhere for inspiration?
  Update 2017-01-23: it can be found there.

A bit of context:

At the current stage, SageMath is both a Python library, and a distribution (comparable in spirit to e.g. anaconda). Disentangling the two is in the work but will take time. In the mean time the installation on an preinstalled Python is cumbersome (although it should be enough to just install the SageMath kernel in the preinstalled Python). Also our docker image already weights 7Gb. Finally it would be slightly simpler / lighter to maintain our docker images if they are all on the same base.

Thanks!

See also: #43.

Cheers,
Nicolas

[nthiery]

Update: There is now a SageMath package in debian unstable and testing, and in principle in the upcoming debian stable as well. Once mybinder's base docker container will be based on the latter, and assuming mybinder's docker configuration enables rather large docker images (plausibly 14G), it should be straightforward to build a mybinder docker image with Sage installd by apt. In that case, this issue could be closed.