Bash Scripting Patterns and Practical Recipes

#!/usr/bin/env bash

SCRIPT_DIR=$(cd -- "$(dirname -- "${BASH_SOURCE[0]}")" && pwd)

while (($#)); do
  case "$1" in
    -v|--verbose) verbose=1 ;;
    -o|--output) output=$2; shift ;;
    *) echo "unknown arg: $1" >&2; exit 1 ;;
  esac
  shift
done

while getopts ':f:o:v' opt; do
  case $opt in
    f) file=$OPTARG ;;
    o) output=$OPTARG ;;
    v) verbose=1 ;;
    \?) echo "invalid option: -$OPTARG" ;;
  esac
done

shift $((OPTIND - 1))

tmp=$(mktemp)

tmpdir=$(mktemp -d)

cmp -s new.conf current.conf || cp new.conf current.conf

if ! command -v jq >/dev/null 2>&1; then echo 'jq required'; exit 1; fi

dir=$PWD
while [[ $dir != / && ! -d $dir/.git ]]; do dir=$(dirname "$dir"); done
echo "$dir"

log() { printf '[%s] %s
' "$(date +%H:%M:%S)" "$*"; }

warn() { printf 'WARN: %s
' "$*" >&2; }
die() { printf 'ERROR: %s
' "$*" >&2; exit 1; }

./deploy.sh 2>&1 | tee deploy.log

for attempt in {1..5}; do
  curl -sf http://localhost:8080/health && break
  sleep 2
done

timeout 30s bash -lc 'long_running_job'

job1 &
pid1=$!
job2 &
pid2=$!
wait "$pid1" "$pid2"

user=$(jq -r '.user.name' payload.json)
echo "$user"

cat > app.env <<EOF
APP_ENV=${APP_ENV:-dev}
PORT=${PORT:-3000}
EOF