qmcgaw/deunhealth repository overview

⁠DeUnhealth

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

1. Use the following command:

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

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   You can also use docker-compose.yml⁠ with:

   docker-compose up -d
   

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2. Set labels on containers:

   • To restart containers if they go unhealthy, use the label deunhealth.restart.on.unhealthy=true

3. 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.

⁠Options

⁠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

1. Install Go⁠, Docker⁠ and Git⁠

2. Install Go dependencies with

   go mod download
   

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3. Install golangci-lint⁠

4. 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

1. Trigger mechanism such that a container restart triggers other restarts
2. 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)
3. Integration tests in Go instead of shell script