DeUnhealth

This is a fork of Quentin McGaw, I just updated the Dockerfile so that I have the latest image of Alpine and the necessary programs

Restart your unhealthy containers safely

Features

Restart unhealthy containers marked with deunhealth.restart.on.unhealthy=true label
Receive Docker events as stream instead of polling periodically
Doesn't need network for security purposes
Compatible with amd64, 386, arm64, arm32v7, arm32v6, ppc64le, s390x and riscv64 CPU architectures
Docker image tags and sizes

Setup

Use the following command:

docker run -d --network none -v /var/run/docker.sock:/var/run/docker.sock qmcgaw/deunhealth

You can also use docker-compose.yml with:

docker-compose up -d

Set labels on containers:
- To restart containers if they go unhealthy, use the label deunhealth.restart.on.unhealthy=true
You can update the image with docker pull qmcgaw/deunhealth:latest or use one of the tags available. ⚠️ You might want to use tagged images since latest will likely break compatibility until we reach a v1.0.0 release.

Environment variables

Environment variable	Default	Possible values	Description
`DOCKER_HOST`	Default Docker socket location	Docker host value	Docker host value such as `unix:///var/run/docker.sock` or `tcp://socket-proxy:2375`
`LOG_LEVEL`	`info`	`debug`, `info`, `warning`, `error`	Logging level
`HEALTH_SERVER_ADDRESS`	`127.0.0.1:9999`	Valid address	Health server listening address
`TZ`	`America/Montreal`	string	Timezone

Safety

The application doesn't need network to reduce the attack surface
Since Docker is written in Go, the program is also written in Go and uses the official Docker Go API
The Docker container is based on scratch to reduce the attack surface and only contains the static binary
The container has to run as root unfortunately 😢

Development

VSCode and Docker

Please refer to the corresponding readme.

Locally

Install Go, Docker and Git
Install Go dependencies with
```
go mod download
```
Install golangci-lint
You might want to use an editor such as Visual Studio Code with the Go extension.

Commands available

# Build the binary
go build cmd/app/main.go
# Test the code
go test ./...
# Lint the code
golangci-lint run
# Build the Docker image
docker build -t qmcgaw/deunhealth .

See Contributing for more information on how to contribute to this repository.

TODOs

Trigger mechanism such that a container restart triggers other restarts
Inject pre-build binary doing a DNS lookup to containers labeled for it and that do not have a healthcheck built in (useful for scratch based images without healthcheck especially)
Integration tests in Go instead of shell script

fatez/deunhealth