bump-spin-formula.sh

#!/bin/bash
set -euo pipefail

VERSION=$1
FORMULA=${2:-Formula/spin.rb}

# -i syntax differs between GNU and Mac sed; this usage is supported by both
SED_INPLACE='sed -i.bak'

# cleanup
trap 'rm checksums.txt **/*.bak &>/dev/null' EXIT

usage() {
  echo "Usage: $0 <VERSION> [<FORMULA_PATH>]"
  echo "Updates the Spin Formula for the specified release version"
  echo "Example: $0 v3.0.0"
}

if [[ $# -ne 1 ]]
then
  usage
  exit 1
fi

# Ensure version is prefixed with 'v' and an 'official' release
if [[ ! "${VERSION}" =~ ^v[0-9]+.[0-9]+.[0-9]+$ ]]
then
  echo "VERSION doesn't match v[0-9]+.[0-9]+.[0-9]+ and may be a prerelease; skipping."
  exit 1
fi

# Get the checksum file for the release
wget -qO checksums.txt "https://github.com/fermyon/spin/releases/download/${VERSION}/checksums-${VERSION}.txt" ||
  (echo "Checksum file not found for version ${VERSION}" && exit 1)

# Remove the 'v' prefix from the version
ERSION="${VERSION:1}"
${SED_INPLACE} -e "s/version \"[^\"]*\"/version \"${ERSION}\"/" "${FORMULA}"
# Update the sha256 checksums for each OS/Arch
while read -r line
do
  filename=$(echo "${line}" | awk '{print $2}')
  sha256=$(echo "${line}" | awk '{print $1}')
  os_arch="${filename//spin-v${ERSION}-/}"
  if grep -q "${os_arch}" "${FORMULA}"
  then
    ${SED_INPLACE} -E "/url \".*${os_arch}\"/ { n; s/sha256 \"[^\"]*\"/sha256 \"${sha256}\"/; }" "${FORMULA}"
  fi
done <checksums.txt

echo "Formula updated to version ${VERSION} with new checksums."