From b3c1e64853bd6ea26cbe7a6e4acbfe19f8ce56b2 Mon Sep 17 00:00:00 2001
From: Wong Hoi Sing Edison <hswong3i@gmail.com>
Date: Tue, 14 Jan 2020 13:23:11 +0800
Subject: [PATCH] https://github.com/docker-library/postgres/pull/496

---
 .../ansible/roles/localhost/tasks/debian.yml  |  24 +-
 .../usr/local/bin/docker-entrypoint.sh.j2     | 354 ++++++++++++------
 .../postgresql/postgresql.conf.sample.j2      |  22 ++
 3 files changed, 282 insertions(+), 118 deletions(-)
 create mode 100644 files/etc/ansible/roles/localhost/templates/usr/share/postgresql/postgresql.conf.sample.j2

diff --git a/files/etc/ansible/roles/localhost/tasks/debian.yml b/files/etc/ansible/roles/localhost/tasks/debian.yml
index 4d5cc72..fae54b9 100644
--- a/files/etc/ansible/roles/localhost/tasks/debian.yml
+++ b/files/etc/ansible/roles/localhost/tasks/debian.yml
@@ -45,10 +45,32 @@
     set -o pipefail
     mv /usr/share/postgresql/{{ postgres_release }}/postgresql.conf.sample /usr/share/postgresql/
     ln -s ../postgresql.conf.sample /usr/share/postgresql/{{ postgres_release }}/postgresql.conf.sample
-    sed -ri "s/^#*listen_addresses.*/listen_addresses = '*'/g" /usr/share/postgresql/postgresql.conf.sample
   args:
     executable: "/bin/bash"
   register: result
   until: result is succeeded
   changed_when: result is not succeeded
   tags: localhost
+
+- name: copy templates
+  template:
+    dest: "{{ item.dest }}"
+    src: "{{ item.src | default('./templates' + item.dest + '.j2') }}"
+    owner: "{{ item.owner | default('root') }}"
+    group: "{{ item.group | default('root') }}"
+    mode: "{{ item.mode | default('0644') }}"
+    backup: true
+  loop:
+    - { dest: "/usr/share/postgresql/postgresql.conf.sample" }
+  tags: localhost
+
+- name: prepare files
+  file:
+    dest: "{{ item.dest }}"
+    owner: "{{ item.owner | default('root') }}"
+    group: "{{ item.group | default('root') }}"
+    mode: "{{ item.mode | default('0644') }}"
+    state: "{{ item.state | default('file') }}"
+  loop:
+    - { dest: "/usr/share/postgresql/postgresql.conf.sample" }
+  tags: localhost
diff --git a/files/etc/ansible/roles/localhost/templates/usr/local/bin/docker-entrypoint.sh.j2 b/files/etc/ansible/roles/localhost/templates/usr/local/bin/docker-entrypoint.sh.j2
index 9f5a221..f51ae03 100644
--- a/files/etc/ansible/roles/localhost/templates/usr/local/bin/docker-entrypoint.sh.j2
+++ b/files/etc/ansible/roles/localhost/templates/usr/local/bin/docker-entrypoint.sh.j2
@@ -27,153 +27,273 @@ file_env() {
 	unset "$fileVar"
 }
 
-if [ "${1:0:1}" = '-' ]; then
-	set -- postgres "$@"
-fi
+# 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)"
 
-# allow the container to be started with `--user`
-if [ "$1" = 'postgres' ] && [ "$(id -u)" = '0' ]; then
 	mkdir -p "$PGDATA"
-	chown -R postgres "$PGDATA"
 	chmod 700 "$PGDATA"
 
-	mkdir -p /var/run/postgresql
-	chown -R postgres /var/run/postgresql
-	chmod 775 /var/run/postgresql
+	# 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 775 /var/run/postgresql || :
 
-	# Create the transaction log directory before initdb is run (below) so the directory is owned by the correct user
+	# Create the transaction log directory before initdb is run so the directory is owned by the correct user
 	if [ "$POSTGRES_INITDB_WALDIR" ]; then
 		mkdir -p "$POSTGRES_INITDB_WALDIR"
-		chown -R postgres "$POSTGRES_INITDB_WALDIR"
+		if [ "$user" = '0' ]; then
+			find "$POSTGRES_INITDB_WALDIR" \! -user postgres -exec chown postgres '{}' +
+		fi
 		chmod 700 "$POSTGRES_INITDB_WALDIR"
 	fi
 
-	exec gosu postgres "$BASH_SOURCE" "$@"
-fi
-
-if [ "$1" = 'postgres' ]; then
-	mkdir -p "$PGDATA"
-	chown -R "$(id -u)" "$PGDATA" 2>/dev/null || :
-	chmod 700 "$PGDATA" 2>/dev/null || :
+	# allow the container to be started with `--user`
+	if [ "$user" = '0' ]; then
+		find "$PGDATA" \! -user postgres -exec chown postgres '{}' +
+		find /var/run/postgresql \! -user postgres -exec chown postgres '{}' +
+	fi
+}
 
-	# look specifically for PG_VERSION, as it is expected in the DB dir
-	if [ ! -s "$PGDATA/PG_VERSION" ]; then
-		# "initdb" is particular about the current user existing in "/etc/passwd", so we use "nss_wrapper" to fake that if necessary
-		# see https://github.com/docker-library/postgres/pull/253, https://github.com/docker-library/postgres/issues/359, https://cwrap.org/nss_wrapper.html
-		if ! getent passwd "$(id -u)" &> /dev/null && [ -e /usr/lib/libnss_wrapper.so ]; then
-			export LD_PRELOAD='/usr/lib/libnss_wrapper.so'
-			export NSS_WRAPPER_PASSWD="$(mktemp)"
-			export NSS_WRAPPER_GROUP="$(mktemp)"
-			echo "postgres:x:$(id -u):$(id -g):PostgreSQL:$PGDATA:/bin/false" > "$NSS_WRAPPER_PASSWD"
-			echo "postgres:x:$(id -g):" > "$NSS_WRAPPER_GROUP"
-		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
+	if ! getent passwd "$(id -u)" &> /dev/null && [ -e /usr/lib/libnss_wrapper.so ]; then
+		export LD_PRELOAD='/usr/lib/libnss_wrapper.so'
+		export NSS_WRAPPER_PASSWD="$(mktemp)"
+		export NSS_WRAPPER_GROUP="$(mktemp)"
+		echo "postgres:x:$(id -u):$(id -g):PostgreSQL:$PGDATA:/bin/false" > "$NSS_WRAPPER_PASSWD"
+		echo "postgres:x:$(id -g):" > "$NSS_WRAPPER_GROUP"
+	fi
 
-		file_env 'POSTGRES_USER' 'postgres'
-		file_env 'POSTGRES_PASSWORD'
+	if [ "$POSTGRES_INITDB_WALDIR" ]; then
+		set -- --waldir "$POSTGRES_INITDB_WALDIR" "$@"
+	fi
 
-		file_env 'POSTGRES_INITDB_ARGS'
-		if [ "$POSTGRES_INITDB_WALDIR" ]; then
-			export POSTGRES_INITDB_ARGS="$POSTGRES_INITDB_ARGS --waldir $POSTGRES_INITDB_WALDIR"
-		fi
-		eval 'initdb --username="$POSTGRES_USER" --pwfile=<(echo "$POSTGRES_PASSWORD") '"$POSTGRES_INITDB_ARGS"
+	eval 'initdb --username="$POSTGRES_USER" --pwfile=<(echo "$POSTGRES_PASSWORD") '"$POSTGRES_INITDB_ARGS"' "$@"'
 
-		# unset/cleanup "nss_wrapper" bits
-		if [ "${LD_PRELOAD:-}" = '/usr/lib/libnss_wrapper.so' ]; then
-			rm -f "$NSS_WRAPPER_PASSWD" "$NSS_WRAPPER_GROUP"
-			unset LD_PRELOAD NSS_WRAPPER_PASSWD NSS_WRAPPER_GROUP
-		fi
+	# unset/cleanup "nss_wrapper" bits
+	if [ "${LD_PRELOAD:-}" = '/usr/lib/libnss_wrapper.so' ]; then
+		rm -f "$NSS_WRAPPER_PASSWD" "$NSS_WRAPPER_GROUP"
+		unset LD_PRELOAD NSS_WRAPPER_PASSWD NSS_WRAPPER_GROUP
+	fi
+}
 
-		# check password first so we can output the warning before postgres
-		# messes it up
-		if [ -n "$POSTGRES_PASSWORD" ]; then
-			authMethod=md5
+# print large warning if POSTGRES_PASSWORD is empty
+docker_verify_minimum_env() {
+	# check password first so we can output the warning before postgres
+	# messes it up
+	if [ "${#POSTGRES_PASSWORD}" -ge 100 ]; then
+		cat >&2 <<-'EOWARN'
 
-			if [ "{{ '${#POSTGRES_PASSWORD}' }}" -ge 100 ]; then
-				cat >&2 <<-'EOWARN'
+			WARNING: The supplied POSTGRES_PASSWORD is 100+ characters.
 
-					WARNING: The supplied POSTGRES_PASSWORD is 100+ characters.
+			  This will not work if used via PGPASSWORD with "psql".
 
-					  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
 
-					  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
+	if [ -z "$POSTGRES_PASSWORD" ]; then
+		# The - option suppresses leading tabs but *not* spaces. :)
+		cat >&2 <<-'EOWARN'
+			****************************************************
+			WARNING: No password has been set for the database.
+			         This will allow anyone with access to the
+			         Postgres port to access your database. In
+			         Docker's default configuration, this is
+			         effectively any other container on the same
+			         system.
 
-				EOWARN
-			fi
-		else
-			# The - option suppresses leading tabs but *not* spaces. :)
-			cat >&2 <<-'EOWARN'
-				****************************************************
-				WARNING: No password has been set for the database.
-				         This will allow anyone with access to the
-				         Postgres port to access your database. In
-				         Docker's default configuration, this is
-				         effectively any other container on the same
-				         system.
-
-				         Use "-e POSTGRES_PASSWORD=password" to set
-				         it in "docker run".
-				****************************************************
-			EOWARN
-
-			authMethod=trust
-		fi
+			         Use "-e POSTGRES_PASSWORD=password" to set
+			         it in "docker run".
+			****************************************************
+		EOWARN
 
-		{
-			echo
-			echo "host all all all $authMethod"
-		} >> "$PGDATA/pg_hba.conf"
+	fi
+}
 
-		# internal start of server in order to allow set-up using psql-client
-		# does not listen on external TCP/IP and waits until start finishes
-		PGUSER="${PGUSER:-$POSTGRES_USER}" \
-		pg_ctl -D "$PGDATA" \
-			-o "-c listen_addresses=''" \
-			-w start
+# usage: docker_process_init_files [file [file [...]]]
+#    ie: docker_process_init_files /always-initdb.d/*
+# process initializer files, based on file extensions and permissions
+docker_process_init_files() {
+	# psql here for backwards compatiblilty "${psql[@]}"
+	psql=( docker_process_sql )
 
-		file_env 'POSTGRES_DB' "$POSTGRES_USER"
+	echo
+	local f
+	for f; do
+		case "$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
+					echo "$0: running $f"
+					"$f"
+				else
+					echo "$0: sourcing $f"
+					. "$f"
+				fi
+				;;
+			*.sql)    echo "$0: running $f"; docker_process_sql -f "$f"; echo ;;
+			*.sql.gz) echo "$0: running $f"; gunzip -c "$f" | docker_process_sql; echo ;;
+			*)        echo "$0: ignoring $f" ;;
+		esac
+		echo
+	done
+}
 
-		export PGPASSWORD="${PGPASSWORD:-$POSTGRES_PASSWORD}"
-		psql=( psql -v ON_ERROR_STOP=1 --username "$POSTGRES_USER" --no-password )
+# Execute sql script, passed via stdin (or -f flag of pqsl)
+# usage: docker_process_sql [psql-cli-args]
+#    ie: docker_process_sql --dbname=mydb <<<'INSERT ...'
+#    ie: docker_process_sql -f my-file.sql
+#    ie: docker_process_sql <my-file.sql
+docker_process_sql() {
+	local query_runner=( psql -v ON_ERROR_STOP=1 --username "$POSTGRES_USER" --no-password )
+	if [ -n "$POSTGRES_DB" ]; then
+		query_runner+=( --dbname "$POSTGRES_DB" )
+	fi
 
-		if [ "$POSTGRES_DB" != 'postgres' ]; then
-			"${psql[@]}" --dbname postgres --set db="$POSTGRES_DB" <<-'EOSQL'
-				CREATE DATABASE :"db" ;
-			EOSQL
-			echo
-		fi
-		psql+=( --dbname "$POSTGRES_DB" )
+	"${query_runner[@]}" "$@"
+}
 
+# create initial database
+# uses environment variables for input: POSTGRES_DB
+docker_setup_db() {
+	if [ "$POSTGRES_DB" != 'postgres' ]; then
+		POSTGRES_DB= docker_process_sql --dbname postgres --set db="$POSTGRES_DB" <<-'EOSQL'
+			CREATE DATABASE :"db" ;
+		EOSQL
 		echo
-		for f in /docker-entrypoint-initdb.d/*; 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
-						echo "$0: running $f"
-						"$f"
-					else
-						echo "$0: sourcing $f"
-						. "$f"
-					fi
-					;;
-				*.sql)    echo "$0: running $f"; "${psql[@]}" -f "$f"; echo ;;
-				*.sql.gz) echo "$0: running $f"; gunzip -c "$f" | "${psql[@]}"; echo ;;
-				*)        echo "$0: ignoring $f" ;;
-			esac
-			echo
-		done
+	fi
+}
 
-		PGUSER="${PGUSER:-$POSTGRES_USER}" \
-		pg_ctl -D "$PGDATA" -m fast -w stop
+# 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'
 
-		unset PGPASSWORD
+	file_env 'POSTGRES_USER' 'postgres'
+	file_env 'POSTGRES_DB' "$POSTGRES_USER"
+	file_env 'POSTGRES_INITDB_ARGS'
 
+	declare -g DATABASE_ALREADY_EXISTS
+	# look specifically for PG_VERSION, as it is expected in the DB dir
+	if [ -s "$PGDATA/PG_VERSION" ]; then
+		DATABASE_ALREADY_EXISTS='true'
+	fi
+}
+
+# append md5 or trust auth to pg_hba.conf based on existence of POSTGRES_PASSWORD
+pg_setup_hba_conf() {
+	local authMethod='md5'
+	if [ -z "$POSTGRES_PASSWORD" ]; then
+		authMethod='trust'
+	fi
+
+	{
 		echo
-		echo 'PostgreSQL init process complete; ready for start up.'
-		echo
+		echo "host all all all $authMethod"
+	} >> "$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
-fi
 
-exec "$@"
+	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
+			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 "$@"
+
+			docker_setup_db
+			docker_process_init_files /docker-entrypoint-initdb.d/*
+
+			docker_temp_server_stop
+			unset PGPASSWORD
+
+			echo
+			echo 'PostgreSQL init process complete; ready for start up.'
+			echo
+		else
+			echo
+			echo 'PostgreSQL Database directory appears to contain a database; Skipping initialization'
+			echo
+		fi
+	fi
+
+	exec "$@"
+}
+
+if ! _is_sourced; then
+	_main "$@"
+fi
diff --git a/files/etc/ansible/roles/localhost/templates/usr/share/postgresql/postgresql.conf.sample.j2 b/files/etc/ansible/roles/localhost/templates/usr/share/postgresql/postgresql.conf.sample.j2
new file mode 100644
index 0000000..7efa5a3
--- /dev/null
+++ b/files/etc/ansible/roles/localhost/templates/usr/share/postgresql/postgresql.conf.sample.j2
@@ -0,0 +1,22 @@
+# {{ ansible_managed }}
+
+autovacuum                 = on
+datestyle                  = 'iso, mdy'
+default_text_search_config = 'pg_catalog.english'
+dynamic_shared_memory_type = posix
+effective_cache_size       = 128MB
+lc_messages                = 'en_US.utf8'
+lc_monetary                = 'en_US.utf8'
+lc_numeric                 = 'en_US.utf8'
+lc_time                    = 'en_US.utf8'
+listen_addresses           = '*'
+log_destination            = 'stderr'
+log_timezone               = 'UTC'
+max_connections            = 128
+max_wal_size               = 1GB
+min_wal_size               = 128MB
+port                       = 5432
+shared_buffers             = 128MB
+timezone                   = 'UTC'
+track_counts               = on
+unix_socket_directories    = '/var/run/postgresql'