pg_basebackup.py

cat basebackup.py 
import io, os
import psycopg2
import tarfile
from contextlib import closing
from datetime import date
from time import time

def add_file(archive, filename, data):
    with closing(io.BytesIO(data.encode())) as f:
        tarinfo = tarfile.TarInfo(filename)
        tarinfo.size = len(f.getvalue())
        tarinfo.mtime = time()
        archive.addfile(tarinfo, fileobj=f)

def main():
    # TODO: Args...
    connection = psycopg2.connect(port=5433)

    cursor = connection.cursor()
    cursor.execute("SELECT pg_start_backup('backup-date', false, false);")

    # result = cursor.fetchone()
    # print(result)

    backup_file = "pgsql-basebackup-{}.tar.xz".format(date.today())
    data_dir = "paf_data-{}".format(date.today())
    tar = tarfile.open(backup_file, "w:xz")
    tar.add("/var/lib/pgsql/12/paf_data", arcname=data_dir)

    cursor.execute("SELECT * FROM pg_stop_backup(false, true);");
    lsn, labelfile_data, spcmapdata = cursor.fetchone();

    add_file(tar, os.path.join(data_dir, 'backup_label'), labelfile_data)
    if spcmapdata:
        add_file(tar, os.path.join(data_dir, 'tablespace_map'), spcmapdata)
    tar.close()
    cursor.close()
    connection.close()

if __name__ == '__main__':
    main()