Cleaning apt-get after each install block slows down docker build

[cmbankester]

We could just move apt-get clean && rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/* to after the last apt-get install.

[ecordell]

It's annoying and slow, but it keeps the docker image much smaller. If you apt-get clean after all the other packages have installed, it will remove the temporary files from the current layer, but not from previous layers. Doing everything in one step keeps each layer as small as possible.

It might be a good idea to have a baseimage (with all of the build tools and language dependencies installed) and then the dockerfile for this project would inherit it and add the macaroon packages...

[cmbankester]

Ah, good point. A base image makes the most sense here. It's just annoying to have to wait for the build, but that's not really a valid issue anyway.

[cmckni3]

Maybe something like conveyor can help.

[rjmunro]

Alternatives to conveyor that may also help (or not):
https://github.com/dnephin/dobi
https://github.com/grammarly/rocker
https://www.packer.io/

See my stack overflow question: http://stackoverflow.com/a/42113114/3408

[Dynom]

A more recent Docker feature (Multi Stage Builds) might be interesting to migrate to: https://docs.docker.com/engine/userguide/eng-image/multistage-build/#use-multi-stage-builds