docker-php-extension-installer/scripts/travisci-update-readme

#!/bin/sh

# Let's set a sane environment
set -o errexit
set -o nounset

UPDATE_README_COMMIT_AUTHOR_NAME='Travis CI'
UPDATE_README_COMMIT_AUTHOR_EMAIL='michele@locati.it'
UPDATE_README_COMMIT_MESSAGE='[skip ci] Automatically update README.md'
WATCHED_FILES='data/special-requirements data/supported-extensions scripts/common scripts/update-readme scripts/travisci-update-readme'

SCRIPTS_DIR="$(CDPATH= cd -- "$(dirname -- "$0")" && pwd)"
. "$SCRIPTS_DIR/common"

echo 'Checking environment'
if test -z "${TRAVIS_BUILD_DIR:-}" || test -z "${TRAVIS_BRANCH:-}" || test -z "${TRAVIS_EVENT_TYPE:-}" || test -z "${TRAVIS_REPO_SLUG:-}"; then
	echo 'Not in a TravisCI environment' >&2
	exit 1
fi
if test -z "${GUTHUB_ACCESS_TOKEN:-}"; then
	echo 'GitHub access token not set' >&2
	# To create it:
	#  - go to https://github.com/settings/tokens/new?scopes=repo
	#  - create a new token
	#  - sudo apt install -y build-essential ruby ruby-dev
	#  - sudo gem install travis
	#  - travis encrypt -r <owner>/<repo> GUTHUB_ACCESS_TOKEN=<TOKEN>
	#  - Add to .travis.yml:
	#    env:
	#      global:
	#        - secure: "encrypted string"
	exit 1
fi
if test "$TRAVIS_EVENT_TYPE" != 'push'; then
	echo 'This script should only be run in push builds' >&2
	exit 1
fi

printf 'Checking-out branch %s\n' "$TRAVIS_BRANCH"
git checkout --force "$TRAVIS_BRANCH"

LAST_AUTO_UPDATED_IN="$(git -C "$TRAVIS_BUILD_DIR" rev-list --max-count 1 --author "<$UPDATE_README_COMMIT_AUTHOR_EMAIL>" --grep "$UPDATE_README_COMMIT_MESSAGE" "$TRAVIS_BRANCH")"
if test -z "$LAST_AUTO_UPDATED_IN"; then
	printf 'Rebuild of README.md enabled (no previous automatic refresh of it in branch %s)\n' "$TRAVIS_BRANCH"
else
	MODIFIED_FILES_SINCE="$(git -C "$TRAVIS_BUILD_DIR" diff --name-only "$LAST_AUTO_UPDATED_IN...$TRAVIS_BRANCH")"
	if test -z "$(commonElements "$WATCHED_FILES" "$MODIFIED_FILES_SINCE")"; then
		printf 'Rebuild of README.md not needed (no relevant files changed in branch %s since commit %s)\n' "$TRAVIS_BRANCH" "$LAST_AUTO_UPDATED_IN"
		exit 0
	fi
	printf 'Rebuild of README.md enabled (relevant files changed in branch %s since commit %s)\n' "$TRAVIS_BRANCH" "$LAST_AUTO_UPDATED_IN"
fi

echo 'Updating README.md'
"$TRAVIS_BUILD_DIR/scripts/update-readme"
if test -z "$(git -C "$TRAVIS_BUILD_DIR" ls-files -m | grep -E '^README\.md$')"; then
	echo 'README.md has not been changed'
	exit 0
fi

printf 'Adding %s remote\n' "$TRAVIS_REPO_SLUG"
git remote add deploy "https://$GUTHUB_ACCESS_TOKEN@github.com/$TRAVIS_REPO_SLUG.git"

echo 'Committing changes to README.md'
git -C "$TRAVIS_BUILD_DIR" config user.name "$UPDATE_README_COMMIT_AUTHOR_NAME"
git -C "$TRAVIS_BUILD_DIR" config user.email "$UPDATE_README_COMMIT_AUTHOR_EMAIL"
git -C "$TRAVIS_BUILD_DIR" add README.md
git -C "$TRAVIS_BUILD_DIR" commit -m "$UPDATE_README_COMMIT_MESSAGE"

printf 'Pushing to %s\n' "$TRAVIS_REPO_SLUG"
git push deploy "$TRAVIS_BRANCH"

echo 'Done.'