create-github-release.sh

#!/usr/bin/env bash

# Creates the release with the latest tag if any release does not already exists
# Example usage:
#   bash "create-github-release.sh" \
#    --repository "undergroundwires/privacy.sexy" \
#    --type "draft" \
#    --token "YOUR_SECRET_PAT"
# Prerequisites:
#   - Ensure your current folder is the repository root & git is installed
#   - Ensure all tags are fetched
# Dependencies:
#   - External: git, curl, jq
#   - Local: ./shared/log-commits.sh, ./shared/utilities.sh

# Globals
readonly SCRIPTS_DIRECTORY="$(cd "$(dirname -- "${BASH_SOURCE[0]}")" >/dev/null 2>&1 && pwd -P)"
readonly LOG_COMMITS_SCRIPT_PATH="${SCRIPTS_DIRECTORY}/shared/log-commits.sh"

# Import dependencies
# shellcheck source=scripts/shared/utilities.sh
source "${SCRIPTS_DIRECTORY}/shared/utilities.sh"

release_exists() {
  local -r version="$1" repository="$2" access_token="$3"
  local -r api_url="https://api.github.com/repos/${repository}/releases/tags/${version}"
  local -i status_code
  if ! status_code=$(curl \
    --write-out '%{http_code}' \
    --silent \
    --output /dev/null \
    --header "Authorization: token ${access_token}" \
    "${api_url}"); then
    echo "Request to check if release exists has failed"
    exit 1
  fi
  echo "${status_code} from ${api_url}"
  if [[ ${status_code} -eq 200 ]]; then
    echo "Skipping creating a release as a release already exists for \"${version}\""
    return 0
  elif [[ ${status_code} -eq 401 ]]; then
    echo "401 Unauthorized: Is release access token valid?"
    return 0
  elif [[ ${status_code} -eq 404 ]]; then
    echo "404 Not Found: \"${version}\" is not yet released"
    return 1
  else
    echo "Unexpected status code: ${status_code}"
    exit 1
  fi
}

print_release_notes() {
  local -r version="$1" repository="$2"
  if utilities::has_single_version; then
    echo "Initial release"
    return 0
  fi
  local version_before
  if ! version_before=$(utilities::print_previous_version); then
    echo "Could not get the previous version. ${version_before}"
    exit 1
  fi
  local changes
  if ! changes=$(bash "${LOG_COMMITS_SCRIPT_PATH}" \
    --repository "${repository}" \
    --current "${version}" \
    --previous "${version_before}"); then
    echo "${LOG_COMMITS_SCRIPT_PATH} has failed"
    exit 1
  fi
  if ! utilities::is_empty_or_null "${changes}"; then
    printf "%s\n\n" "${changes}"
  fi
  printf "[compare](https://github.com/%s/compare/%s...%s)" \
    "${repository}" "${version_before}" "${version}"
}

create_release() {
  local -r version="$1" repository="$2" access_token="$3" release_type="$4"
  echo "Creating a new release for ${version}"
  local changelog
  if ! changelog=$(print_release_notes "${version}" "${repository}"); then
    echo "print_release_notes has failed"
    exit 1
  fi
  local json_payload # https://developer.github.com/v3/repos/releases/#create-a-release
  if ! json_payload=$(jq -n \
    --arg version "${version}" \
    --arg body "${changelog}" \
    '{ tag_name: $version, name: $version, body: $body }'); then
    echo "jq has failed"
    exit 1
  fi
  if is_release_type_draft "${release_type}"; then
    json_payload=$(echo "${json_payload}" | jq --argjson value true '. + {draft: $value}')
  fi
  if is_release_type_prerelease "${release_type}"; then
    json_payload=$(echo "${json_payload}" | jq --argjson value true '. + {prerelease: $value}')
  fi
  curl --header "Authorization: token ${access_token}" \
    "https://api.github.com/repos/${repository}/releases" \
    --data "${json_payload}" \
    --silent \
    --fail
}

is_release_type_draft() { utilities::equals_case_insensitive "$1" "draft"; }
is_release_type_none() { utilities::equals_case_insensitive "$1" "none"; }
is_release_type_prerelease() { utilities::equals_case_insensitive "$1" "prerelease"; }
is_release_type_release() { utilities::equals_case_insensitive "$1" "release"; }

validate_parameters() {
  local repository="$1" access_token="$2" release_type="$3"
  if utilities::is_empty_or_null "${repository}"; then
    echo "Repository name is not set."
    exit 1
  fi
  if utilities::is_empty_or_null "${release_type}"; then
    echo "Release type is not set."
    exit 1
  fi
  if ! (is_release_type_draft "${release_type}" ||
    is_release_type_none "${release_type}" ||
    is_release_type_prerelease "${release_type}" ||
    is_release_type_release "${release_type}"); then
    echo "Unkown release type: \"${release_type}\"."
    exit 1
  fi
  if (! is_release_type_none "${release_type}") &&
    utilities::is_empty_or_null "${access_token}"; then
    echo "Access token is not set."
    exit 1
  fi
}

main() {
  local -r repository="$1" access_token="$2" release_type="$3"
  validate_parameters "${repository}" "${access_token}" "${release_type}"
  if is_release_type_none "${release_type}"; then
    echo "Skipping release as release type is set to \"${release_type}\""
    exit 0
  fi
  local latest_version
  if ! latest_version=$(utilities::print_latest_version); then
    echo "Could not get the latest version. ${latest_version}"
    exit 1
  fi
  if ! release_exists "${latest_version}" "${repository}" "${access_token}"; then
    create_release "${latest_version}" "${repository}" "${access_token}" "${release_type}"
  fi
}

while [[ $# -gt 0 ]]; do
  case $1 in
  --repository)
    REPOSITORY="$2"
    shift
    ;;
  --token)
    ACCESS_TOKEN="$2"
    shift
    ;;
  --type)
    RELEASE_TYPE="$2"
    shift
    ;;
  *)
    echo "Unknown parameter passed: $1"
    exit 1
    ;;
  esac
  shift
done

main "${REPOSITORY}" "${ACCESS_TOKEN}" "${RELEASE_TYPE}"