[aaron42net]

I grant the docker.io build and private repository service access to my github repo, drop a Dockerfile at the root of my git repo, and the build server does the checkout outside of the Dockerfile and then executes the Dockerfile. I then use a github webhook to trigger a build when there's a new checkin to the master or qa branches. If the dockerfile completes successfully (based on exit status codes), it then spits out new docker images tagged with either "master" or "qa".

My fleet unit does a docker pull before it starts the container. So I just stop and start an individual unit to get it to run a new version.

Though fleet has a concept of global units (that run on all available machines), there's no way to do a rolling restart with them yet. Instead, I use unit templates to launch multiple instances of the same unit, and then stop and start each instance individually, and wait for it to respond before continuing to the next one. I intend to catch a webhook from the build server and do this automatically, but haven't written this yet.