beatflip 🧚

a minimal supervisor

Beatflip is a minimal supervisor tailored to single-process applications. It comes with the following features:

• 💚 Process uptime: monitors processes and restarts them if exited
• 🧃 OTA updates: downloads newer versions against an update-server / S3 bucket, flips & restarts binaries
• 📮 Log handling: forwards process output

Installation

To install / update beatflip run

go install github.com/wakurobotics/beatflip@latest

Docker

git clone github.com/wakurobotics/beatflip && cd beatflip
docker build -t wakurobotics/beatflip .
docker run wakurobotics/beatflip --help

Usage

$ beatflip --help
Usage:
  beatflip [command]

Available Commands:
  completion  Generate the autocompletion script for the specified shell
  help        Help about any command
  init        initialize a new configuration file in the current directoey
  supervise
  version

Flags:
      --config string   config file (default is '.beatflip.yml')
  -h, --help            help for beatflip

Use "beatflip [command] --help" for more information about a command.

beatflip init

Initialize a new configuration file.

beatflip supervise

Start the supervisor mode.

Config-File

You can initialize a new configuration file via beatflip init.

By default, Beatflip looks for a config file named .beatflip.yml in the current working directory. This can be overridden via the --config flag.

For a full example of the configuration file, please have a look at https://github.com/wakurobotics/beatflip/raw/master/cmd/.beatflip.yml.

OS Signals

Sending a SIGINT or SIGTERM to beatflip causes the supervisor to first terminate the supervised process by forwarding the respective signal, then terminating itself.

Sending a SIGHUB to the supervisor causes it to restart a currently running process.

beatflip supervise &
PID=$!
kill -HUP $PID  # --> supervised process will be restarted