From 5b0a72d95dab3d5678825b1bba0a0ffb8d75e3ab Mon Sep 17 00:00:00 2001
From: pao <pao@Wired>
Date: Tue, 7 May 2024 09:32:33 +0700
Subject: [PATCH 1/2] Add script check exist database before initdb

---
 .project                                      |  11 +
 16/bookworm-no-initdb-if-exist/-Dockerfile-   | 226 +++++++++++
 16/bookworm-no-initdb-if-exist/Containerfile  |   6 +
 .../docker-ensure-initdb.sh                   |  71 ++++
 .../docker-ensure-no-initdb-if-exist.sh       |  76 ++++
 .../docker-entrypoint.sh                      | 356 ++++++++++++++++++
 16/bookworm-no-initdb-if-exist/load-image.sh  |  20 +
 7 files changed, 766 insertions(+)
 create mode 100644 .project
 create mode 100644 16/bookworm-no-initdb-if-exist/-Dockerfile-
 create mode 100644 16/bookworm-no-initdb-if-exist/Containerfile
 create mode 100755 16/bookworm-no-initdb-if-exist/docker-ensure-initdb.sh
 create mode 100755 16/bookworm-no-initdb-if-exist/docker-ensure-no-initdb-if-exist.sh
 create mode 100755 16/bookworm-no-initdb-if-exist/docker-entrypoint.sh
 create mode 100755 16/bookworm-no-initdb-if-exist/load-image.sh

diff --git a/.project b/.project
new file mode 100644
index 0000000000..228b765b04
--- /dev/null
+++ b/.project
@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<projectDescription>
+	<name>postgres</name>
+	<comment></comment>
+	<projects>
+	</projects>
+	<buildSpec>
+	</buildSpec>
+	<natures>
+	</natures>
+</projectDescription>
diff --git a/16/bookworm-no-initdb-if-exist/-Dockerfile- b/16/bookworm-no-initdb-if-exist/-Dockerfile-
new file mode 100644
index 0000000000..6bcb1b873a
--- /dev/null
+++ b/16/bookworm-no-initdb-if-exist/-Dockerfile-
@@ -0,0 +1,226 @@
+#
+# NOTE: THIS DOCKERFILE IS GENERATED VIA "apply-templates.sh"
+#
+# PLEASE DO NOT EDIT IT DIRECTLY.
+#
+
+FROM debian:bookworm-slim
+
+# explicitly set user/group IDs
+RUN set -eux; \
+	groupadd -r postgres --gid=999; \
+# https://salsa.debian.org/postgresql/postgresql-common/blob/997d842ee744687d99a2b2d95c1083a2615c79e8/debian/postgresql-common.postinst#L32-35
+	useradd -r -g postgres --uid=999 --home-dir=/var/lib/postgresql --shell=/bin/bash postgres; \
+# also create the postgres user's home directory with appropriate permissions
+# see https://github.com/docker-library/postgres/issues/274
+	mkdir -p /var/lib/postgresql; \
+	chown -R postgres:postgres /var/lib/postgresql
+
+RUN set -ex; \
+	apt-get update; \
+	apt-get install -y --no-install-recommends \
+		gnupg \
+# https://www.postgresql.org/docs/16/app-psql.html#APP-PSQL-META-COMMAND-PSET-PAGER
+# https://github.com/postgres/postgres/blob/REL_16_1/src/include/fe_utils/print.h#L25
+# (if "less" is available, it gets used as the default pager for psql, and it only adds ~1.5MiB to our image size)
+		less \
+	; \
+	rm -rf /var/lib/apt/lists/*
+
+# grab gosu for easy step-down from root
+# https://github.com/tianon/gosu/releases
+ENV GOSU_VERSION 1.17
+RUN set -eux; \
+	savedAptMark="$(apt-mark showmanual)"; \
+	apt-get update; \
+	apt-get install -y --no-install-recommends ca-certificates wget; \
+	rm -rf /var/lib/apt/lists/*; \
+	dpkgArch="$(dpkg --print-architecture | awk -F- '{ print $NF }')"; \
+	wget -O /usr/local/bin/gosu "https://github.com/tianon/gosu/releases/download/$GOSU_VERSION/gosu-$dpkgArch"; \
+	wget -O /usr/local/bin/gosu.asc "https://github.com/tianon/gosu/releases/download/$GOSU_VERSION/gosu-$dpkgArch.asc"; \
+	export GNUPGHOME="$(mktemp -d)"; \
+	gpg --batch --keyserver hkps://keys.openpgp.org --recv-keys B42F6819007F00F88E364FD4036A9C25BF357DD4; \
+	gpg --batch --verify /usr/local/bin/gosu.asc /usr/local/bin/gosu; \
+	gpgconf --kill all; \
+	rm -rf "$GNUPGHOME" /usr/local/bin/gosu.asc; \
+	apt-mark auto '.*' > /dev/null; \
+	[ -z "$savedAptMark" ] || apt-mark manual $savedAptMark > /dev/null; \
+	apt-get purge -y --auto-remove -o APT::AutoRemove::RecommendsImportant=false; \
+	chmod +x /usr/local/bin/gosu; \
+	gosu --version; \
+	gosu nobody true
+
+# make the "en_US.UTF-8" locale so postgres will be utf-8 enabled by default
+RUN set -eux; \
+	if [ -f /etc/dpkg/dpkg.cfg.d/docker ]; then \
+# if this file exists, we're likely in "debian:xxx-slim", and locales are thus being excluded so we need to remove that exclusion (since we need locales)
+		grep -q '/usr/share/locale' /etc/dpkg/dpkg.cfg.d/docker; \
+		sed -ri '/\/usr\/share\/locale/d' /etc/dpkg/dpkg.cfg.d/docker; \
+		! grep -q '/usr/share/locale' /etc/dpkg/dpkg.cfg.d/docker; \
+	fi; \
+	apt-get update; apt-get install -y --no-install-recommends locales; rm -rf /var/lib/apt/lists/*; \
+	echo 'en_US.UTF-8 UTF-8' >> /etc/locale.gen; \
+	locale-gen; \
+	locale -a | grep 'en_US.utf8'
+ENV LANG en_US.utf8
+
+RUN set -eux; \
+	apt-get update; \
+	apt-get install -y --no-install-recommends \
+		libnss-wrapper \
+		xz-utils \
+		zstd \
+	; \
+	rm -rf /var/lib/apt/lists/*
+
+RUN mkdir /docker-entrypoint-initdb.d
+
+RUN set -ex; \
+# pub   4096R/ACCC4CF8 2011-10-13 [expires: 2019-07-02]
+#       Key fingerprint = B97B 0AFC AA1A 47F0 44F2  44A0 7FCC 7D46 ACCC 4CF8
+# uid                  PostgreSQL Debian Repository
+	key='B97B0AFCAA1A47F044F244A07FCC7D46ACCC4CF8'; \
+	export GNUPGHOME="$(mktemp -d)"; \
+	mkdir -p /usr/local/share/keyrings/; \
+	gpg --batch --keyserver keyserver.ubuntu.com --recv-keys "$key"; \
+	gpg --batch --export --armor "$key" > /usr/local/share/keyrings/postgres.gpg.asc; \
+	gpgconf --kill all; \
+	rm -rf "$GNUPGHOME"
+
+ENV PG_MAJOR 16
+ENV PATH $PATH:/usr/lib/postgresql/$PG_MAJOR/bin
+
+ENV PG_VERSION 16.2-1.pgdg120+2
+
+RUN set -ex; \
+	\
+# see note below about "*.pyc" files
+	export PYTHONDONTWRITEBYTECODE=1; \
+	\
+	dpkgArch="$(dpkg --print-architecture)"; \
+	aptRepo="[ signed-by=/usr/local/share/keyrings/postgres.gpg.asc ] http://apt.postgresql.org/pub/repos/apt/ bookworm-pgdg main $PG_MAJOR"; \
+	case "$dpkgArch" in \
+		amd64 | arm64 | ppc64el | s390x) \
+# arches officialy built by upstream
+			echo "deb $aptRepo" > /etc/apt/sources.list.d/pgdg.list; \
+			apt-get update; \
+			;; \
+		*) \
+# we're on an architecture upstream doesn't officially build for
+# let's build binaries from their published source packages
+			echo "deb-src $aptRepo" > /etc/apt/sources.list.d/pgdg.list; \
+			\
+			savedAptMark="$(apt-mark showmanual)"; \
+			\
+			tempDir="$(mktemp -d)"; \
+			cd "$tempDir"; \
+			\
+# create a temporary local APT repo to install from (so that dependency resolution can be handled by APT, as it should be)
+			apt-get update; \
+			apt-get install -y --no-install-recommends dpkg-dev; \
+			echo "deb [ trusted=yes ] file://$tempDir ./" > /etc/apt/sources.list.d/temp.list; \
+			_update_repo() { \
+				dpkg-scanpackages . > Packages; \
+# work around the following APT issue by using "Acquire::GzipIndexes=false" (overriding "/etc/apt/apt.conf.d/docker-gzip-indexes")
+#   Could not open file /var/lib/apt/lists/partial/_tmp_tmp.ODWljpQfkE_._Packages - open (13: Permission denied)
+#   ...
+#   E: Failed to fetch store:/var/lib/apt/lists/partial/_tmp_tmp.ODWljpQfkE_._Packages  Could not open file /var/lib/apt/lists/partial/_tmp_tmp.ODWljpQfkE_._Packages - open (13: Permission denied)
+				apt-get -o Acquire::GzipIndexes=false update; \
+			}; \
+			_update_repo; \
+			\
+# build .deb files from upstream's source packages (which are verified by apt-get)
+			nproc="$(nproc)"; \
+			export DEB_BUILD_OPTIONS="nocheck parallel=$nproc"; \
+# we have to build postgresql-common first because postgresql-$PG_MAJOR shares "debian/rules" logic with it: https://salsa.debian.org/postgresql/postgresql/-/commit/99f44476e258cae6bf9e919219fa2c5414fa2876
+# (and it "Depends: pgdg-keyring")
+			apt-get build-dep -y postgresql-common pgdg-keyring; \
+			apt-get source --compile postgresql-common pgdg-keyring; \
+			_update_repo; \
+			apt-get build-dep -y "postgresql-$PG_MAJOR=$PG_VERSION"; \
+			apt-get source --compile "postgresql-$PG_MAJOR=$PG_VERSION"; \
+			\
+# we don't remove APT lists here because they get re-downloaded and removed later
+			\
+# reset apt-mark's "manual" list so that "purge --auto-remove" will remove all build dependencies
+# (which is done after we install the built packages so we don't have to redownload any overlapping dependencies)
+			apt-mark showmanual | xargs apt-mark auto > /dev/null; \
+			apt-mark manual $savedAptMark; \
+			\
+			ls -lAFh; \
+			_update_repo; \
+			grep '^Package: ' Packages; \
+			cd /; \
+			;; \
+	esac; \
+	\
+	apt-get install -y --no-install-recommends postgresql-common; \
+	sed -ri 's/#(create_main_cluster) .*$/\1 = false/' /etc/postgresql-common/createcluster.conf; \
+	apt-get install -y --no-install-recommends \
+		"postgresql-$PG_MAJOR=$PG_VERSION" \
+	; \
+	\
+	rm -rf /var/lib/apt/lists/*; \
+	\
+	if [ -n "$tempDir" ]; then \
+# if we have leftovers from building, let's purge them (including extra, unnecessary build deps)
+		apt-get purge -y --auto-remove; \
+		rm -rf "$tempDir" /etc/apt/sources.list.d/temp.list; \
+	fi; \
+	\
+# some of the steps above generate a lot of "*.pyc" files (and setting "PYTHONDONTWRITEBYTECODE" beforehand doesn't propagate properly for some reason), so we clean them up manually (as long as they aren't owned by a package)
+	find /usr -name '*.pyc' -type f -exec bash -c 'for pyc; do dpkg -S "$pyc" &> /dev/null || rm -vf "$pyc"; done' -- '{}' +; \
+	\
+	postgres --version
+
+# make the sample config easier to munge (and "correct by default")
+RUN set -eux; \
+	dpkg-divert --add --rename --divert "/usr/share/postgresql/postgresql.conf.sample.dpkg" "/usr/share/postgresql/$PG_MAJOR/postgresql.conf.sample"; \
+	cp -v /usr/share/postgresql/postgresql.conf.sample.dpkg /usr/share/postgresql/postgresql.conf.sample; \
+	ln -sv ../postgresql.conf.sample "/usr/share/postgresql/$PG_MAJOR/"; \
+	sed -ri "s!^#?(listen_addresses)\s*=\s*\S+.*!\1 = '*'!" /usr/share/postgresql/postgresql.conf.sample; \
+	grep -F "listen_addresses = '*'" /usr/share/postgresql/postgresql.conf.sample
+
+RUN mkdir -p /var/run/postgresql && chown -R postgres:postgres /var/run/postgresql && chmod 3777 /var/run/postgresql
+
+ENV PGDATA /var/lib/postgresql/data
+# this 1777 will be replaced by 0700 at runtime (allows semi-arbitrary "--user" values)
+RUN mkdir -p "$PGDATA" && chown -R postgres:postgres "$PGDATA" && chmod 1777 "$PGDATA"
+VOLUME /var/lib/postgresql/data
+
+COPY docker-entrypoint.sh docker-ensure-initdb.sh /usr/local/bin/
+RUN ln -sT docker-ensure-initdb.sh /usr/local/bin/docker-enforce-initdb.sh
+ENTRYPOINT ["docker-entrypoint.sh"]
+
+# We set the default STOPSIGNAL to SIGINT, which corresponds to what PostgreSQL
+# calls "Fast Shutdown mode" wherein new connections are disallowed and any
+# in-progress transactions are aborted, allowing PostgreSQL to stop cleanly and
+# flush tables to disk, which is the best compromise available to avoid data
+# corruption.
+#
+# Users who know their applications do not keep open long-lived idle connections
+# may way to use a value of SIGTERM instead, which corresponds to "Smart
+# Shutdown mode" in which any existing sessions are allowed to finish and the
+# server stops when all sessions are terminated.
+#
+# See https://www.postgresql.org/docs/12/server-shutdown.html for more details
+# about available PostgreSQL server shutdown signals.
+#
+# See also https://www.postgresql.org/docs/12/server-start.html for further
+# justification of this as the default value, namely that the example (and
+# shipped) systemd service files use the "Fast Shutdown mode" for service
+# termination.
+#
+STOPSIGNAL SIGINT
+#
+# An additional setting that is recommended for all users regardless of this
+# value is the runtime "--stop-timeout" (or your orchestrator/runtime's
+# equivalent) for controlling how long to wait between sending the defined
+# STOPSIGNAL and sending SIGKILL (which is likely to cause data corruption).
+#
+# The default in most runtimes (such as Docker) is 10 seconds, and the
+# documentation at https://www.postgresql.org/docs/12/server-start.html notes
+# that even 90 seconds may not be long enough in many instances.
+
+EXPOSE 5432
+CMD ["postgres"]
diff --git a/16/bookworm-no-initdb-if-exist/Containerfile b/16/bookworm-no-initdb-if-exist/Containerfile
new file mode 100644
index 0000000000..83cd98a3d1
--- /dev/null
+++ b/16/bookworm-no-initdb-if-exist/Containerfile
@@ -0,0 +1,6 @@
+FROM postgres:16
+
+COPY docker-ensure-no-initdb-if-exist.sh /usr/local/bin/docker-ensure-initdb.sh
+RUN rm -f /usr/local/bin/docker-enforce-initdb.sh && ln -sT docker-ensure-initdb.sh /usr/local/bin/docker-enforce-initdb.sh
+
+ENTRYPOINT ["docker-entrypoint.sh"]
diff --git a/16/bookworm-no-initdb-if-exist/docker-ensure-initdb.sh b/16/bookworm-no-initdb-if-exist/docker-ensure-initdb.sh
new file mode 100755
index 0000000000..ae1f6b6b90
--- /dev/null
+++ b/16/bookworm-no-initdb-if-exist/docker-ensure-initdb.sh
@@ -0,0 +1,71 @@
+#!/usr/bin/env bash
+set -Eeuo pipefail
+
+#
+# This script is intended for three main use cases:
+#
+#  1. (most importantly) as an example of how to use "docker-entrypoint.sh" to extend/reuse the initialization behavior
+#
+#  2. ("docker-ensure-initdb.sh") as a Kubernetes "init container" to ensure the provided database directory is initialized; see also "startup probes" for an alternative solution
+#       (no-op if database is already initialized)
+#
+#  3. ("docker-enforce-initdb.sh") as part of CI to ensure the database is fully initialized before use
+#       (error if database is already initialized)
+#
+
+source /usr/local/bin/docker-entrypoint.sh
+
+# arguments to this script are assumed to be arguments to the "postgres" server (same as "docker-entrypoint.sh"), and most "docker-entrypoint.sh" functions assume "postgres" is the first argument (see "_main" over there)
+if [ "$#" -eq 0 ] || [ "$1" != 'postgres' ]; then
+	set -- postgres "$@"
+fi
+
+# see also "_main" in "docker-entrypoint.sh"
+
+docker_setup_env
+# setup data directories and permissions (when run as root)
+docker_create_db_directories
+if [ "$(id -u)" = '0' ]; then
+	# then restart script as postgres user
+	exec gosu postgres "$BASH_SOURCE" "$@"
+fi
+
+# only run initialization on an empty data directory
+if [ -z "$DATABASE_ALREADY_EXISTS" ]; then
+	docker_verify_minimum_env
+
+	# check dir permissions to reduce likelihood of half-initialized database
+	ls /docker-entrypoint-initdb.d/ > /dev/null
+
+	docker_init_database_dir
+	pg_setup_hba_conf "$@"
+
+	# PGPASSWORD is required for psql when authentication is required for 'local' connections via pg_hba.conf and is otherwise harmless
+	# e.g. when '--auth=md5' or '--auth-local=md5' is used in POSTGRES_INITDB_ARGS
+	export PGPASSWORD="${PGPASSWORD:-$POSTGRES_PASSWORD}"
+	docker_temp_server_start "$@"
+
+	docker_setup_db
+	docker_process_init_files /docker-entrypoint-initdb.d/*
+
+	docker_temp_server_stop
+	unset PGPASSWORD
+else
+	self="$(basename "$0")"
+	case "$self" in
+		docker-ensure-initdb.sh)
+			echo >&2 "$self: note: database already initialized in '$PGDATA'!"
+			exit 0
+			;;
+
+		docker-enforce-initdb.sh)
+			echo >&2 "$self: error: (unexpected) database found in '$PGDATA'!"
+			exit 1
+			;;
+
+		*)
+			echo >&2 "$self: error: unknown file name: $self"
+			exit 99
+			;;
+	esac
+fi
diff --git a/16/bookworm-no-initdb-if-exist/docker-ensure-no-initdb-if-exist.sh b/16/bookworm-no-initdb-if-exist/docker-ensure-no-initdb-if-exist.sh
new file mode 100755
index 0000000000..788f3c61a5
--- /dev/null
+++ b/16/bookworm-no-initdb-if-exist/docker-ensure-no-initdb-if-exist.sh
@@ -0,0 +1,76 @@
+#!/usr/bin/env bash
+set -Eeuo pipefail
+
+#
+# This script is intended for three main use cases:
+#
+#  1. (most importantly) as an example of how to use "docker-entrypoint.sh" to extend/reuse the initialization behavior
+#
+#  2. ("docker-ensure-initdb.sh") as a Kubernetes "init container" to ensure the provided database directory is initialized; see also "startup probes" for an alternative solution
+#       (no-op if database is already initialized)
+#
+#  3. ("docker-enforce-initdb.sh") as part of CI to ensure the database is fully initialized before use
+#       (error if database is already initialized)
+#
+
+source /usr/local/bin/docker-entrypoint.sh
+
+# arguments to this script are assumed to be arguments to the "postgres" server (same as "docker-entrypoint.sh"), and most "docker-entrypoint.sh" functions assume "postgres" is the first argument (see "_main" over there)
+if [ "$#" -eq 0 ] || [ "$1" != 'postgres' ]; then
+	set -- postgres "$@"
+fi
+
+# see also "_main" in "docker-entrypoint.sh"
+
+docker_setup_env
+# setup data directories and permissions (when run as root)
+docker_create_db_directories
+if [ "$(id -u)" = '0' ]; then
+	# then restart script as postgres user
+	exec gosu postgres "$BASH_SOURCE" "$@"
+fi
+
+# only run initialization on an empty data directory
+if [ -z "$DATABASE_ALREADY_EXISTS" ]; then
+	docker_verify_minimum_env
+
+	# check dir permissions to reduce likelihood of half-initialized database
+	ls /docker-entrypoint-initdb.d/ > /dev/null
+
+	# Check if the PGDATA directory contains a PG_VERSION file
+	if [ ! -f "$PGDATA/PG_VERSION" ]; then
+	    docker_init_database_dir
+	else
+	    echo "Database already initialized in $PGDATA, skipping initdb."
+	fi
+	pg_setup_hba_conf "$@"
+
+	# PGPASSWORD is required for psql when authentication is required for 'local' connections via pg_hba.conf and is otherwise harmless
+	# e.g. when '--auth=md5' or '--auth-local=md5' is used in POSTGRES_INITDB_ARGS
+	export PGPASSWORD="${PGPASSWORD:-$POSTGRES_PASSWORD}"
+	docker_temp_server_start "$@"
+
+	docker_setup_db
+	docker_process_init_files /docker-entrypoint-initdb.d/*
+
+	docker_temp_server_stop
+	unset PGPASSWORD
+else
+	self="$(basename "$0")"
+	case "$self" in
+		docker-ensure-initdb.sh)
+			echo >&2 "$self: note: database already initialized in '$PGDATA'!"
+			exit 0
+			;;
+
+		docker-enforce-initdb.sh)
+			echo >&2 "$self: error: (unexpected) database found in '$PGDATA'!"
+			exit 1
+			;;
+
+		*)
+			echo >&2 "$self: error: unknown file name: $self"
+			exit 99
+			;;
+	esac
+fi
diff --git a/16/bookworm-no-initdb-if-exist/docker-entrypoint.sh b/16/bookworm-no-initdb-if-exist/docker-entrypoint.sh
new file mode 100755
index 0000000000..6f59993e08
--- /dev/null
+++ b/16/bookworm-no-initdb-if-exist/docker-entrypoint.sh
@@ -0,0 +1,356 @@
+#!/usr/bin/env bash
+set -Eeo pipefail
+# TODO swap to -Eeuo pipefail above (after handling all potentially-unset variables)
+
+# usage: file_env VAR [DEFAULT]
+#    ie: file_env 'XYZ_DB_PASSWORD' 'example'
+# (will allow for "$XYZ_DB_PASSWORD_FILE" to fill in the value of
+#  "$XYZ_DB_PASSWORD" from a file, especially for Docker's secrets feature)
+file_env() {
+	local var="$1"
+	local fileVar="${var}_FILE"
+	local def="${2:-}"
+	if [ "${!var:-}" ] && [ "${!fileVar:-}" ]; then
+		printf >&2 'error: both %s and %s are set (but are exclusive)\n' "$var" "$fileVar"
+		exit 1
+	fi
+	local val="$def"
+	if [ "${!var:-}" ]; then
+		val="${!var}"
+	elif [ "${!fileVar:-}" ]; then
+		val="$(< "${!fileVar}")"
+	fi
+	export "$var"="$val"
+	unset "$fileVar"
+}
+
+# check to see if this file is being run or sourced from another script
+_is_sourced() {
+	# https://unix.stackexchange.com/a/215279
+	[ "${#FUNCNAME[@]}" -ge 2 ] \
+		&& [ "${FUNCNAME[0]}" = '_is_sourced' ] \
+		&& [ "${FUNCNAME[1]}" = 'source' ]
+}
+
+# used to create initial postgres directories and if run as root, ensure ownership to the "postgres" user
+docker_create_db_directories() {
+	local user; user="$(id -u)"
+
+	mkdir -p "$PGDATA"
+	# ignore failure since there are cases where we can't chmod (and PostgreSQL might fail later anyhow - it's picky about permissions of this directory)
+	chmod 00700 "$PGDATA" || :
+
+	# ignore failure since it will be fine when using the image provided directory; see also https://github.com/docker-library/postgres/pull/289
+	mkdir -p /var/run/postgresql || :
+	chmod 03775 /var/run/postgresql || :
+
+	# Create the transaction log directory before initdb is run so the directory is owned by the correct user
+	if [ -n "${POSTGRES_INITDB_WALDIR:-}" ]; then
+		mkdir -p "$POSTGRES_INITDB_WALDIR"
+		if [ "$user" = '0' ]; then
+			find "$POSTGRES_INITDB_WALDIR" \! -user postgres -exec chown postgres '{}' +
+		fi
+		chmod 700 "$POSTGRES_INITDB_WALDIR"
+	fi
+
+	# allow the container to be started with `--user`
+	if [ "$user" = '0' ]; then
+		find "$PGDATA" \! -user postgres -exec chown postgres '{}' +
+		find /var/run/postgresql \! -user postgres -exec chown postgres '{}' +
+	fi
+}
+
+# initialize empty PGDATA directory with new database via 'initdb'
+# arguments to `initdb` can be passed via POSTGRES_INITDB_ARGS or as arguments to this function
+# `initdb` automatically creates the "postgres", "template0", and "template1" dbnames
+# this is also where the database user is created, specified by `POSTGRES_USER` env
+docker_init_database_dir() {
+	# "initdb" is particular about the current user existing in "/etc/passwd", so we use "nss_wrapper" to fake that if necessary
+	# see https://github.com/docker-library/postgres/pull/253, https://github.com/docker-library/postgres/issues/359, https://cwrap.org/nss_wrapper.html
+	local uid; uid="$(id -u)"
+	if ! getent passwd "$uid" &> /dev/null; then
+		# see if we can find a suitable "libnss_wrapper.so" (https://salsa.debian.org/sssd-team/nss-wrapper/-/commit/b9925a653a54e24d09d9b498a2d913729f7abb15)
+		local wrapper
+		for wrapper in {/usr,}/lib{/*,}/libnss_wrapper.so; do
+			if [ -s "$wrapper" ]; then
+				NSS_WRAPPER_PASSWD="$(mktemp)"
+				NSS_WRAPPER_GROUP="$(mktemp)"
+				export LD_PRELOAD="$wrapper" NSS_WRAPPER_PASSWD NSS_WRAPPER_GROUP
+				local gid; gid="$(id -g)"
+				printf 'postgres:x:%s:%s:PostgreSQL:%s:/bin/false\n' "$uid" "$gid" "$PGDATA" > "$NSS_WRAPPER_PASSWD"
+				printf 'postgres:x:%s:\n' "$gid" > "$NSS_WRAPPER_GROUP"
+				break
+			fi
+		done
+	fi
+
+	if [ -n "${POSTGRES_INITDB_WALDIR:-}" ]; then
+		set -- --waldir "$POSTGRES_INITDB_WALDIR" "$@"
+	fi
+
+	# --pwfile refuses to handle a properly-empty file (hence the "\n"): https://github.com/docker-library/postgres/issues/1025
+	eval 'initdb --username="$POSTGRES_USER" --pwfile=<(printf "%s\n" "$POSTGRES_PASSWORD") '"$POSTGRES_INITDB_ARGS"' "$@"'
+
+	# unset/cleanup "nss_wrapper" bits
+	if [[ "${LD_PRELOAD:-}" == */libnss_wrapper.so ]]; then
+		rm -f "$NSS_WRAPPER_PASSWD" "$NSS_WRAPPER_GROUP"
+		unset LD_PRELOAD NSS_WRAPPER_PASSWD NSS_WRAPPER_GROUP
+	fi
+}
+
+# print large warning if POSTGRES_PASSWORD is long
+# error if both POSTGRES_PASSWORD is empty and POSTGRES_HOST_AUTH_METHOD is not 'trust'
+# print large warning if POSTGRES_HOST_AUTH_METHOD is set to 'trust'
+# assumes database is not set up, ie: [ -z "$DATABASE_ALREADY_EXISTS" ]
+docker_verify_minimum_env() {
+	case "${PG_MAJOR:-}" in
+		12 | 13) # https://github.com/postgres/postgres/commit/67a472d71c98c3d2fa322a1b4013080b20720b98
+			# check password first so we can output the warning before postgres
+			# messes it up
+			if [ "${#POSTGRES_PASSWORD}" -ge 100 ]; then
+				cat >&2 <<-'EOWARN'
+
+					WARNING: The supplied POSTGRES_PASSWORD is 100+ characters.
+
+					  This will not work if used via PGPASSWORD with "psql".
+
+					  https://www.postgresql.org/message-id/flat/E1Rqxp2-0004Qt-PL%40wrigleys.postgresql.org (BUG #6412)
+					  https://github.com/docker-library/postgres/issues/507
+
+				EOWARN
+			fi
+			;;
+	esac
+	if [ -z "$POSTGRES_PASSWORD" ] && [ 'trust' != "$POSTGRES_HOST_AUTH_METHOD" ]; then
+		# The - option suppresses leading tabs but *not* spaces. :)
+		cat >&2 <<-'EOE'
+			Error: Database is uninitialized and superuser password is not specified.
+			       You must specify POSTGRES_PASSWORD to a non-empty value for the
+			       superuser. For example, "-e POSTGRES_PASSWORD=password" on "docker run".
+
+			       You may also use "POSTGRES_HOST_AUTH_METHOD=trust" to allow all
+			       connections without a password. This is *not* recommended.
+
+			       See PostgreSQL documentation about "trust":
+			       https://www.postgresql.org/docs/current/auth-trust.html
+		EOE
+		exit 1
+	fi
+	if [ 'trust' = "$POSTGRES_HOST_AUTH_METHOD" ]; then
+		cat >&2 <<-'EOWARN'
+			********************************************************************************
+			WARNING: POSTGRES_HOST_AUTH_METHOD has been set to "trust". This will allow
+			         anyone with access to the Postgres port to access your database without
+			         a password, even if POSTGRES_PASSWORD is set. See PostgreSQL
+			         documentation about "trust":
+			         https://www.postgresql.org/docs/current/auth-trust.html
+			         In Docker's default configuration, this is effectively any other
+			         container on the same system.
+
+			         It is not recommended to use POSTGRES_HOST_AUTH_METHOD=trust. Replace
+			         it with "-e POSTGRES_PASSWORD=password" instead to set a password in
+			         "docker run".
+			********************************************************************************
+		EOWARN
+	fi
+}
+
+# usage: docker_process_init_files [file [file [...]]]
+#    ie: docker_process_init_files /always-initdb.d/*
+# process initializer files, based on file extensions and permissions
+docker_process_init_files() {
+	# psql here for backwards compatibility "${psql[@]}"
+	psql=( docker_process_sql )
+
+	printf '\n'
+	local f
+	for f; do
+		case "$f" in
+			*.sh)
+				# https://github.com/docker-library/postgres/issues/450#issuecomment-393167936
+				# https://github.com/docker-library/postgres/pull/452
+				if [ -x "$f" ]; then
+					printf '%s: running %s\n' "$0" "$f"
+					"$f"
+				else
+					printf '%s: sourcing %s\n' "$0" "$f"
+					. "$f"
+				fi
+				;;
+			*.sql)     printf '%s: running %s\n' "$0" "$f"; docker_process_sql -f "$f"; printf '\n' ;;
+			*.sql.gz)  printf '%s: running %s\n' "$0" "$f"; gunzip -c "$f" | docker_process_sql; printf '\n' ;;
+			*.sql.xz)  printf '%s: running %s\n' "$0" "$f"; xzcat "$f" | docker_process_sql; printf '\n' ;;
+			*.sql.zst) printf '%s: running %s\n' "$0" "$f"; zstd -dc "$f" | docker_process_sql; printf '\n' ;;
+			*)         printf '%s: ignoring %s\n' "$0" "$f" ;;
+		esac
+		printf '\n'
+	done
+}
+
+# Execute sql script, passed via stdin (or -f flag of pqsl)
+# usage: docker_process_sql [psql-cli-args]
+#    ie: docker_process_sql --dbname=mydb <<<'INSERT ...'
+#    ie: docker_process_sql -f my-file.sql
+#    ie: docker_process_sql <my-file.sql
+docker_process_sql() {
+	local query_runner=( psql -v ON_ERROR_STOP=1 --username "$POSTGRES_USER" --no-password --no-psqlrc )
+	if [ -n "$POSTGRES_DB" ]; then
+		query_runner+=( --dbname "$POSTGRES_DB" )
+	fi
+
+	PGHOST= PGHOSTADDR= "${query_runner[@]}" "$@"
+}
+
+# create initial database
+# uses environment variables for input: POSTGRES_DB
+docker_setup_db() {
+	local dbAlreadyExists
+	dbAlreadyExists="$(
+		POSTGRES_DB= docker_process_sql --dbname postgres --set db="$POSTGRES_DB" --tuples-only <<-'EOSQL'
+			SELECT 1 FROM pg_database WHERE datname = :'db' ;
+		EOSQL
+	)"
+	if [ -z "$dbAlreadyExists" ]; then
+		POSTGRES_DB= docker_process_sql --dbname postgres --set db="$POSTGRES_DB" <<-'EOSQL'
+			CREATE DATABASE :"db" ;
+		EOSQL
+		printf '\n'
+	fi
+}
+
+# Loads various settings that are used elsewhere in the script
+# This should be called before any other functions
+docker_setup_env() {
+	file_env 'POSTGRES_PASSWORD'
+
+	file_env 'POSTGRES_USER' 'postgres'
+	file_env 'POSTGRES_DB' "$POSTGRES_USER"
+	file_env 'POSTGRES_INITDB_ARGS'
+	: "${POSTGRES_HOST_AUTH_METHOD:=}"
+
+	declare -g DATABASE_ALREADY_EXISTS
+	: "${DATABASE_ALREADY_EXISTS:=}"
+	# look specifically for PG_VERSION, as it is expected in the DB dir
+	if [ -s "$PGDATA/PG_VERSION" ]; then
+		DATABASE_ALREADY_EXISTS='true'
+	fi
+}
+
+# append POSTGRES_HOST_AUTH_METHOD to pg_hba.conf for "host" connections
+# all arguments will be passed along as arguments to `postgres` for getting the value of 'password_encryption'
+pg_setup_hba_conf() {
+	# default authentication method is md5 on versions before 14
+	# https://www.postgresql.org/about/news/postgresql-14-released-2318/
+	if [ "$1" = 'postgres' ]; then
+		shift
+	fi
+	local auth
+	# check the default/configured encryption and use that as the auth method
+	auth="$(postgres -C password_encryption "$@")"
+	: "${POSTGRES_HOST_AUTH_METHOD:=$auth}"
+	{
+		printf '\n'
+		if [ 'trust' = "$POSTGRES_HOST_AUTH_METHOD" ]; then
+			printf '# warning trust is enabled for all connections\n'
+			printf '# see https://www.postgresql.org/docs/12/auth-trust.html\n'
+		fi
+		printf 'host all all all %s\n' "$POSTGRES_HOST_AUTH_METHOD"
+	} >> "$PGDATA/pg_hba.conf"
+}
+
+# start socket-only postgresql server for setting up or running scripts
+# all arguments will be passed along as arguments to `postgres` (via pg_ctl)
+docker_temp_server_start() {
+	if [ "$1" = 'postgres' ]; then
+		shift
+	fi
+
+	# internal start of server in order to allow setup using psql client
+	# does not listen on external TCP/IP and waits until start finishes
+	set -- "$@" -c listen_addresses='' -p "${PGPORT:-5432}"
+
+	PGUSER="${PGUSER:-$POSTGRES_USER}" \
+	pg_ctl -D "$PGDATA" \
+		-o "$(printf '%q ' "$@")" \
+		-w start
+}
+
+# stop postgresql server after done setting up user and running scripts
+docker_temp_server_stop() {
+	PGUSER="${PGUSER:-postgres}" \
+	pg_ctl -D "$PGDATA" -m fast -w stop
+}
+
+# check arguments for an option that would cause postgres to stop
+# return true if there is one
+_pg_want_help() {
+	local arg
+	for arg; do
+		case "$arg" in
+			# postgres --help | grep 'then exit'
+			# leaving out -C on purpose since it always fails and is unhelpful:
+			# postgres: could not access the server configuration file "/var/lib/postgresql/data/postgresql.conf": No such file or directory
+			-'?'|--help|--describe-config|-V|--version)
+				return 0
+				;;
+		esac
+	done
+	return 1
+}
+
+_main() {
+	# if first arg looks like a flag, assume we want to run postgres server
+	if [ "${1:0:1}" = '-' ]; then
+		set -- postgres "$@"
+	fi
+
+	if [ "$1" = 'postgres' ] && ! _pg_want_help "$@"; then
+		docker_setup_env
+		# setup data directories and permissions (when run as root)
+		docker_create_db_directories
+		if [ "$(id -u)" = '0' ]; then
+			# then restart script as postgres user
+			exec gosu postgres "$BASH_SOURCE" "$@"
+		fi
+
+		# only run initialization on an empty data directory
+		if [ -z "$DATABASE_ALREADY_EXISTS" ]; then
+			docker_verify_minimum_env
+
+			# check dir permissions to reduce likelihood of half-initialized database
+			ls /docker-entrypoint-initdb.d/ > /dev/null
+
+			docker_init_database_dir
+			pg_setup_hba_conf "$@"
+
+			# PGPASSWORD is required for psql when authentication is required for 'local' connections via pg_hba.conf and is otherwise harmless
+			# e.g. when '--auth=md5' or '--auth-local=md5' is used in POSTGRES_INITDB_ARGS
+			export PGPASSWORD="${PGPASSWORD:-$POSTGRES_PASSWORD}"
+			docker_temp_server_start "$@"
+
+			docker_setup_db
+			docker_process_init_files /docker-entrypoint-initdb.d/*
+
+			docker_temp_server_stop
+			unset PGPASSWORD
+
+			cat <<-'EOM'
+
+				PostgreSQL init process complete; ready for start up.
+
+			EOM
+		else
+			cat <<-'EOM'
+
+				PostgreSQL Database directory appears to contain a database; Skipping initialization
+
+			EOM
+		fi
+	fi
+
+	exec "$@"
+}
+
+if ! _is_sourced; then
+	_main "$@"
+fi
diff --git a/16/bookworm-no-initdb-if-exist/load-image.sh b/16/bookworm-no-initdb-if-exist/load-image.sh
new file mode 100755
index 0000000000..cd56ff2fe0
--- /dev/null
+++ b/16/bookworm-no-initdb-if-exist/load-image.sh
@@ -0,0 +1,20 @@
+#!/bin/bash
+
+# Check if version argument is provided
+if [ -z "$1" ]; then
+  echo "Usage: $0 <version>"
+  exit 1
+fi
+
+version="$1"
+
+podman build -t postgres-local-16:$version .
+
+# Get the image ID
+image_id=$(podman images | awk -v version="$version" '$1 == "localhost/postgres-local-16" && $2 == version {print $3}')
+
+# Tag the image
+podman tag "${image_id}" "localhost:32000/postgres-local-16:${version}"
+
+# Push the tagged image
+podman push --tls-verify=false "localhost:32000/postgres-local-16:${version}" "localhost:32000/postgres-local-16:${version}"

From 126dfdee70c8469e945ad5ab5721e191c657392f Mon Sep 17 00:00:00 2001
From: pao <pao@Wired>
Date: Wed, 8 May 2024 10:15:16 +0700
Subject: [PATCH 2/2] Add container file

---
 16/bookworm-no-initdb-if-exist/Containerfile | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/16/bookworm-no-initdb-if-exist/Containerfile b/16/bookworm-no-initdb-if-exist/Containerfile
index 83cd98a3d1..371b61287b 100644
--- a/16/bookworm-no-initdb-if-exist/Containerfile
+++ b/16/bookworm-no-initdb-if-exist/Containerfile
@@ -1,6 +1,9 @@
 FROM postgres:16
 
-COPY docker-ensure-no-initdb-if-exist.sh /usr/local/bin/docker-ensure-initdb.sh
-RUN rm -f /usr/local/bin/docker-enforce-initdb.sh && ln -sT docker-ensure-initdb.sh /usr/local/bin/docker-enforce-initdb.sh
+# Set working directory
+WORKDIR /var/lib/postgresql/data
 
-ENTRYPOINT ["docker-entrypoint.sh"]
+# Check if the database directory exists (indicates existing data)
+RUN [ ! -d "$PGDATA" ] && echo "Database directory not found, initializing..." || echo "Database directory found, skipping initialization."
+
+#ENTRYPOINT ["docker-entrypoint.sh"]
