docker-shifter

Bash script that simplifies the rollback of the docker compose services to their previous versions.

Imagine a situation where you have a custom-built Docker image, and after deployment, you need to roll back to the previous version with zero downtime. This script does exactly that! It can handle several custom images - each corresponding to a different service.

You can build specific images, start and stop the Docker Compose stack, and roll out or roll back your services with no downtime.

Requirements

Docker rollout plugin installed: https://github.com/Wowu/docker-rollout

Getting started

To make it easy for you to get started with docker-shifter, here's a list of recommended next steps.

Installation

be sure that you have sudo permissions

# Install docker rollout
# Create directory for Docker cli plugins
mkdir -p ~/.docker/cli-plugins

# Download docker-rollout script to Docker cli plugins directory
curl https://raw.githubusercontent.com/wowu/docker-rollout/master/docker-rollout -o ~/.docker/cli-plugins/docker-rollout
# Make the script executable
chmod +x ~/.docker/cli-plugins/docker-rollout

# Install docker shifter Docker cli plugins directory
curl https://raw.githubusercontent.com/dyedfox/docker-shifter/main/plugin/docker-shifter -o ~/.docker/cli-plugins/docker-shifter
# Make the script executable
chmod +x ~/.docker/cli-plugins/docker-shifter

Copy docker-shifter.conf to your project's root and edit it to match your setup:

nano docker-shifter.conf

Example of docker-shifter.conf file

SERVICES["web1"]="my_image1"
SERVICES["web2"]="my_image2"
ENV_VARS["web1"]="ROLL_IMAGE1"
ENV_VARS["web2"]="ROLL_IMAGE2"
DOCKERFILES["web1"]="Dockerfile"
DOCKERFILES["web2"]="Dockerfile.dev"

Where:

DOCKER_COMPOSE_FILE : path to your actual docker-compose configuration file

SERVICES["service"]="image_name" : service name (as in the docker-compose file) and the image name that should be built

ENV_VARS["service"]="ROLL_IMAGE1" : service name and the variable name that matches the service (see example below)

DOCKERFILES["service"]="Dockerfile": service name and the path to the Dockerfile that matches the service

Example:

    ...
      web1:
    image: ${ROLL_IMAGE1}
    ...

Also refer to the docker-compose.yaml, and the mock-up Dockerfile and Dockerfile.dev files (examples directory).

Commands and options

docker-shifter <action> [service]

Actions:

build                  - Build a Docker image

up                     - Build (if necessary) and start containers

rollout                - Update a service with the new image

rollout --non-custom   - Rollout/rollback a non-custom service

(Info: Rollback for custom image is essentially the same as rollout. Please refer to the documentation)

rollback               - Rollback a service to the previous image

down                   - Stop and remove containers, networks, and volumes