Showing posts from December, 2014

Docker - Things I'd like to see fixed

Recently I've been lucky enough to spend some time with Docker.  I've really enjoyed it and would definitely consider myself a fan.  However I think a couple of issues really need fixing. Docker registries should treat images as immutable entities Currently docker registries (including docker hub) allow you to overwrite an image with the same tag.  This means you can't be sure that an image hasn't changed since you last pulled it.  This is a nightmare from a build and deploy point of view.  I can imagine a sequence of events whereby a small low risk change is pushed through the environments with plenty of testing, only to fail in production when suddenly a modified and incompatible dependent image is pulled and deployed for the first time.  Sadly it seems that this  issue has been closed  - presumably without a fix. Registry locations and Image tags need to be separate entities Uniquely identifying a specific docker image and a source/destination regist