docker-postgres-backup/docker-entrypoint.sh

#!/usr/bin/env bash
set -e

if [ "${POSTGRES_INDEX}" != "" ]
then
  set_var_value()
  {
    var_name="${1}"_"${POSTGRES_INDEX}"
    export "${1}"="${!var_name}"
  }

  set_var_value POSTGRES_DISABLED
  set_var_value POSTGRES_SLAVE_MODE
  set_var_value POSTGRES_MASTER_MODE
  set_var_value POSTGRES_NO_BACKUP
  set_var_value POSTGRES_HOST
  set_var_value POSTGRES_USER
  set_var_value POSTGRES_PASSWORD
  set_var_value POSTGRES_DB
  set_var_value POSTGRES_REP_HOST
  set_var_value POSTGRES_REP_PORT
  set_var_value POSTGRES_REP_USER
  set_var_value POSTGRES_REP_PASSWORD
  set_var_value POSTGRES_REP_ALLOWED_HOST
  set_var_value POSTGRES_RO_USER
  set_var_value POSTGRES_RO_PASSWORD
fi

if [ "${POSTGRES_DISABLED}" == 1 ]
then
  echo "Database ${POSTGRES_INDEX} is disabled. Exiting."
  exit 0
fi

if [ "${POSTGRES_SLAVE_MODE}" == 1 ] && [ "${POSTGRES_MASTER_MODE}" == 1 ]
then
  echo "Misconfiguration: master and slave mode are both enabled. Exiting."
  exit 64
fi

if [ "$(id -u)" == "0" ]
then
  cron
fi

# 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
		echo >&2 "error: both $var and $fileVar are set (but are exclusive)"
		exit 1
	fi
	local val="$def"
	if [ "${!var:-}" ]; then
		val="${!var}"
	elif [ "${!fileVar:-}" ]; then
		val="$(< "${!fileVar}")"
	fi
	export "$var"="$val"
	unset "$fileVar"
}

if [ "${1:0:1}" = '-' ]; then
	set -- postgres "$@"
fi

# 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

	# Create the transaction log directory before initdb is run (below) so the directory is owned by the correct user
	if [ "$POSTGRES_INITDB_XLOGDIR" ]; then
		mkdir -p "$POSTGRES_INITDB_XLOGDIR"
		chown -R postgres "$POSTGRES_INITDB_XLOGDIR"
		chmod 700 "$POSTGRES_INITDB_XLOGDIR"
	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 || :

        if [ "${POSTGRES_SLAVE_MODE}" != 1 ]
        then

	    # look specifically for PG_VERSION, as it is expected in the DB dir
	    if [ ! -s "$PGDATA/PG_VERSION" ]; then
		file_env 'POSTGRES_INITDB_ARGS'
		if [ "$POSTGRES_INITDB_XLOGDIR" ]; then
			export POSTGRES_INITDB_ARGS="$POSTGRES_INITDB_ARGS --xlogdir $POSTGRES_INITDB_XLOGDIR"
		fi
		eval "initdb --username=postgres $POSTGRES_INITDB_ARGS"

		# check password first so we can output the warning before postgres
		# messes it up
		file_env 'POSTGRES_PASSWORD'
		if [ "$POSTGRES_PASSWORD" ]; then
			pass="PASSWORD '$POSTGRES_PASSWORD'"
			authMethod=md5
		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

			pass=
			authMethod=trust
		fi

		{
			echo
			echo "host all all all $authMethod"
		} >> "$PGDATA/pg_hba.conf"

		# 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="${PGUSER:-postgres}" \
		pg_ctl -D "$PGDATA" \
			-o "-c listen_addresses='localhost'" \
			-w start

		file_env 'POSTGRES_USER' 'postgres'
		file_env 'POSTGRES_DB' "$POSTGRES_USER"

		echo

                export PGUSER="postgres"
                export PGDATABASE="postgres"
                echo "Running core migrate"
                migrate.py --folder /docker-entrypoint-initdb-core.d/ --init

                export PGUSER="${POSTGRES_USER}"
                export PGDATABASE="${POSTGRES_DB}"
                echo "Running user migrate"
                migrate.py --folder /docker-entrypoint-initdb.d/ --init

		PGUSER="${PGUSER:-postgres}" \
		pg_ctl -D "$PGDATA" -m fast -w stop

		echo
		echo 'PostgreSQL init process complete; ready for start up.'
		echo
	    fi
        else
            echo "Setting up slave..."

            rm -rf "${PGDATA}"/*

            PGPASSWORD="${POSTGRES_REP_PASSWORD}" pg_basebackup -h "${POSTGRES_REP_HOST}" -p "${POSTGRES_REP_PORT}" -D "${PGDATA}" -U "${POSTGRES_REP_USER}" -v

            export PGUSER="postgres"
            export PGDATABASE="postgres"
            echo "Running core migrate"
            migrate.py --folder /docker-entrypoint-initdb-core.d/ --init

            echo
            echo 'PostgreSQL init process complete; ready for start up.'
            echo
        fi
fi

exec "$@"