Shell script template

template.sh

#!/bin/bash -e

trap_handler()
{
    ERRLINE="$1"
    ERRVAL="$2"
    echo "line ${ERRLINE} exit status: ${ERRVAL}"
    # The script should usually exit on error
    exit $ERRVAL
}
trap 'trap_handler ${LINENO} $?' ERR

for REQUIRED in git jq
do
    if ! which $REQUIRED >/dev/null 2>&1
    then
        echo "Required '$REQUIRED' not found in \$PATH"
    fi
done

while getopts ":t:" OPT; do
    case $OPT in
    t )
        target=$OPTARG
        ;;
    \? )
        echo "Invalid option: $OPTARG" >&2
        ;;
    : )
        echo "Invalid option: $OPTARG requires an argument" >&2
        ;;
    esac
done
shift $((OPTIND -1))