[ekidd]

OK, that makes sense.

Since you asked, the drawback of just logging into an image, editing files, and installing software is that you can only reproduce that image by grabbing an entire file system.

When I use Docker, I create a git repository containing a 'Dockerfile', which is basically a series of shell commands to configure a machine. I also add copies of any configuration files I'll need, and use the Dockerfile to copy them onto the machine during setup.

This can be extremely fast in practice: Docker has a caching system which "runs" unchanged lines in Dockerfile by looking up a cached VM image, so I can often edit the Dockerfile and rebuild the image in a second or so.

This approach is really nice when I have to look at an image a year later and figure out how I created it, perhaps with the goal of upgrading to a new OS release or whatever. I just glance at the Dockerfile, change the base OS version, and re-run it.

[sp332]

I wonder if the UI could be improved. Like a "dockerfile creator" that lets you log in and make changes, then at the end lets you look at a list of changes or "history" entries and selectively pull them into a dockerfile.

[opendais]

http://blog.codiez.co.za/2013/09/setup-a-docker-container-wi...

sudo docker run -i -t ubuntu /bin/bash sudo docker commit [container id] [tag]

Is that what you are looking for?

[wmf]

docker commit produces an opaque container image that's not documented or repeatable.

[vidarh]

"docker diff [container]" will show you what files have changed since the image was started, and you can then "docker cp" files out of the container to the host.

But for my part I tend to just layer changes piece by piece. So e.g. I have a docker image that's a "base development" image, and create separate docker containers to run each web app I'm experimenting with, with a shared volume with a separate docker container that I ssh into and run a screen session in with the code/git repositories. In effect that means that bringing up a new docker image for a new project is at most a couple of lines of change unless the project has particular/different dependencies.