Droot is a super-easy application container engine to build, ship, run with chroot instead of docker run, and with Amazon S3 instead of docker registry. It aims to simply escape dependency hell.

Docker has a powerful concept about an application deployment process, that is Build, Ship, Run. But there are many cases that docker runtime is too complicated and beyond our current capabilities, especially on production.

Droot provides a simpler container runtime without annoying Linux Namespaces. Droot depends on traditional Linux functions such as chroot(2), Linux capabilities(7) and a bind mount. droot helps you to chroot a container image built by docker and to import/export container images on Amazon S3.

• Build: docker build
• Ship: Upload images to S3, and Download images from S3.
• Run: chroot(2), Linux capabilities(7), and a bind mount.

• Docker (droot push only depends on it)
• Linux (droot run and droot umount only supports it)

$ brew tap yuuki1/droot
$ brew install droot

Releases・yuuki1/droot - GitHub

 $ go get github.com/yuuki1/droot
 $ go install github.com/yuuki1/droot/cmd

$ droot push --to s3://drootexamples/app.tar.gz dockerfiles/app

$ droot pull --dest /var/containers/app --src s3://drootexamples/app.tar.gz

$ sudo droot run --bind /var/log/ --root /var/containers/app command

$ sudo droot umount --root /var/containers/app

$ sudo droot rm --root /var/containers/app

Droot push/pull subcommands support the following methods to set your AWS credentials.

• an IAM instance profile. http://docs.aws.amazon.com/codedeploy/latest/userguide/how-to-create-iam-instance-profile.html
• Environment variables.

$ export AWS_ACCESS_KEY_ID=********
$ export AWS_SECRET_ACCESS_KEY=********
$ export AWS_REGION=********

• ~/.aws/credentials a standard to manage credentials in the AWS SDKs

Droot push supports the environment variables same as docker-machine such as DOCKER_HOST, DOCKER_TLS_VERIFY, DOCKER_CERT_PATH. ex.

DOCKER_TLS_VERIFY=1
DOCKER_HOST=tcp://192.168.x.x:2376
DOCKER_CERT_PATH=/home/yuuki/.docker/machine/machines/dev

• rmi command to clean a image on S3
• pull command with the rsync option
• push/pull other compression algorithms
• image versioning
• pull from docker registry
• drivers except Amazon S3
• run reads .docekrenv, .dockerinit
• reduce fork&exec
• push/pull S3 download/upload part-size options
• push/pull verifying sha256sum
• pull backup/rollback option

Droot uses a library with cgo, so it is necessary to build in Linux for a Linux binary. It is recommanded to use Docker for development if you are on OSX and other OSs.

$ ./script/build_in_container.sh

1. Fork (https://github.com/yuuki1/droot/fork)
2. Create a feature branch
3. Commit your changes
4. Rebase your local changes against the master branch
5. Run test suite with the make test command and confirm that it passes
6. Create a new Pull Request

y_uuki