devenv.sh

#!/bin/sh

# Exit immediately if a command fails.
set -e
# Treat unset variables as errors.
set -u

# Name of the Docker Compose service for the development environment.
readonly SERVICE="devenv"

# Function to show a help message about this shell script.
help(){
    # Print the help message line by line with a single command.
    printf "%s\n"\
        "Manage development environment containers."\
        ""\
        "Usage: ${0} [help | start | stop]"\
        ""\
        "Commands:"\
        "  help   Show this help message. Default command."\
        "  start  Start a container."\
        "  stop   Stop all containers."
}

# Function to start a development environment container.
start(){
    # Run the Docker Compose command to start the service.
    docker compose run --quiet-pull --rm "${SERVICE}" 2>/dev/null
}

# Function to stop all development environment containers.
stop(){
    # Run the Docker Compose command to stop the service.
    docker compose kill "${SERVICE}" 2>/dev/null
}

# Check that the number of arguments of the script is at most one.
if [ $# -gt 1 ]; then
    >&2 echo "Too many arguments, expected at most one."
    return 1
fi

# Command to run taken from the optional argument. Defaults to "help".
readonly COMMAND="${1:-"help"}"

# Try to run the command.
case "${COMMAND}" in
    # Run the command if it's either "help", "start", or "stop".
    "help"|"start"|"stop")
        "${COMMAND}"
        ;;
    # Show an error message otherwise explaining that the argument is invalid.
    *)
        >&2 echo "Invalid argument, expected \"help\", \"start\", or \"stop\"."
        return 1
        ;;
esac