docker-entrypoint

#!/usr/bin/env bash

EC2_JOIN=
function ec2_members() {
    if [ -z ${AWS_CONTAINER_CREDENTIALS_RELATIVE_URI+x} ]; then
        return
    fi

    local region=$(wget http://169.254.169.254/latest/meta-data/placement/availability-zone -q -O- | sed 's/[a-z]$//')

    mkdir -p ~/.aws
    echo "[default]" > ~/.aws/config
    echo "output = json" >> ~/.aws/config
    echo "region = $region" >> ~/.aws/config

    AWS_TAG=${AWS_TAG:=dkron=member}

    AWS_TAG_NAME=$(echo $AWS_TAG | cut -f1 -d=)
    AWS_TAG_VALUE=$(echo $AWS_TAG | cut -f2 -d=)

    EC2_JOIN=$(aws ec2 describe-instances --filters Name=tag:${AWS_TAG_NAME},Values=${AWS_TAG_VALUE} | jq ".Reservations | map(.Instances)[][].PrivateIpAddress" | cut -f2 -d'"' | paste -sd ";" - | sed -e "s/;/ --join /g")
    if [ -n "$EC2_JOIN" ]; then
        EC2_JOIN=$(echo " --join $EC2_JOIN")
    fi
}

ec2_members
export EC2_JOIN

# first arg is `-f` or `--some-option`
if [ "${1#-}" != "$1" ]; then
	set -- /opt/local/dkron/dkron "$@"
elif [ "$1" == 'agent' -o "$1" == 'keygen' -o "$1" == 'version' ]; then
    set -- /opt/local/dkron/dkron "$@"
fi

exec "$@"