TISbackup/libtisbackup/common.py

#!/usr/bin/python3
# -*- coding: utf-8 -*-
# -----------------------------------------------------------------------
#    This file is part of TISBackup
#
#    TISBackup is free software: you can redistribute it and/or modify
#    it under the terms of the GNU General Public License as published by
#    the Free Software Foundation, either version 3 of the License, or
#    (at your option) any later version.
#
#    TISBackup is distributed in the hope that it will be useful,
#    but WITHOUT ANY WARRANTY; without even the implied warranty of
#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#    GNU General Public License for more details.
#
#    You should have received a copy of the GNU General Public License
#    along with TISBackup.  If not, see <http://www.gnu.org/licenses/>.
#
# -----------------------------------------------------------------------

import datetime
import errno
import logging
import os
import re
import select
import shutil
import sqlite3
import subprocess
import sys
import time
from abc import ABC, abstractmethod

from iniparse import ConfigParser

try:
    sys.stderr = open("/dev/null")  # Silence silly warnings from paramiko
    import paramiko
except ImportError as e:
    print(("Error : can not load paramiko library %s" % e))
    raise

sys.stderr = sys.__stderr__

nagiosStateOk = 0
nagiosStateWarning = 1
nagiosStateCritical = 2
nagiosStateUnknown = 3

backup_drivers = {}


def register_driver(driverclass):
    backup_drivers[driverclass.type] = driverclass


def datetime2isodate(adatetime=None):
    if not adatetime:
        adatetime = datetime.datetime.now()
    assert isinstance(adatetime, datetime.datetime)
    return adatetime.isoformat()


def isodate2datetime(isodatestr):
    # we remove the microseconds part as it is not working for python2.5 strptime
    return datetime.datetime.strptime(isodatestr.split(".")[0], "%Y-%m-%dT%H:%M:%S")


def time2display(adatetime):
    return adatetime.strftime("%Y-%m-%d %H:%M")


def hours_minutes(hours):
    if hours is None:
        return None
    else:
        return "%02i:%02i" % (int(hours), int((hours - int(hours)) * 60.0))


def fileisodate(filename):
    return datetime.datetime.fromtimestamp(os.stat(filename).st_mtime).isoformat()


def dateof(adatetime):
    return adatetime.replace(hour=0, minute=0, second=0, microsecond=0)


#####################################
# http://code.activestate.com/recipes/498181-add-thousands-separator-commas-to-formatted-number/
# Code from Michael Robellard's comment made 28 Feb 2010
# Modified for leading +, -, space on 1 Mar 2010 by Glenn Linderman
#
# Tail recursion removed and  leading garbage handled on March 12 2010, Alessandro Forghieri
def splitThousands(s, tSep=",", dSep="."):
    """Splits a general float on thousands. GIGO on general input"""
    if s is None:
        return 0
    if not isinstance(s, str):
        s = str(s)

    cnt = 0
    numChars = dSep + "0123456789"
    ls = len(s)
    while cnt < ls and s[cnt] not in numChars:
        cnt += 1

    lhs = s[0:cnt]
    s = s[cnt:]
    if dSep == "":
        cnt = -1
    else:
        cnt = s.rfind(dSep)
    if cnt > 0:
        rhs = dSep + s[cnt + 1 :]
        s = s[:cnt]
    else:
        rhs = ""

    splt = ""
    while s != "":
        splt = s[-3:] + tSep + splt
        s = s[:-3]

    return lhs + splt[:-1] + rhs


def call_external_process(shell_string):
    p = subprocess.call(shell_string, shell=True)
    if p != 0:
        raise Exception("shell program exited with error code " + str(p), shell_string)


def check_string(test_string):
    pattern = r"[^\.A-Za-z0-9\-_]"
    if re.search(pattern, test_string):
        # Character other then . a-z 0-9 was found
        print(("Invalid : %r" % (test_string,)))


def convert_bytes(bytes):
    if bytes is None:
        return None
    else:
        bytes = float(bytes)
        if bytes >= 1099511627776:
            terabytes = bytes / 1099511627776
            size = "%.2fT" % terabytes
        elif bytes >= 1073741824:
            gigabytes = bytes / 1073741824
            size = "%.2fG" % gigabytes
        elif bytes >= 1048576:
            megabytes = bytes / 1048576
            size = "%.2fM" % megabytes
        elif bytes >= 1024:
            kilobytes = bytes / 1024
            size = "%.2fK" % kilobytes
        else:
            size = "%.2fb" % bytes
        return size


## {{{ http://code.activestate.com/recipes/81189/ (r2)
def pp(cursor, data=None, rowlens=0, callback=None):
    """
    pretty print a query result as a table
    callback is a function called for each field (fieldname,value) to format the output
    """

    def defaultcb(fieldname, value):
        return value

    if not callback:
        callback = defaultcb

    d = cursor.description
    if not d:
        return "#### NO RESULTS ###"
    names = []
    lengths = []
    rules = []
    if not data:
        data = cursor.fetchall()
    for dd in d:  # iterate over description
        l = dd[1]
        if not l:
            l = 12  # or default arg ...
        l = max(l, len(dd[0]))  # handle long names
        names.append(dd[0])
        lengths.append(l)
    for col in range(len(lengths)):
        if rowlens:
            rls = [len(str(callback(d[col][0], row[col]))) for row in data if row[col]]
            lengths[col] = max([lengths[col]] + rls)
        rules.append("-" * lengths[col])
    format = " ".join(["%%-%ss" % l for l in lengths])
    result = [format % tuple(names)]
    result.append(format % tuple(rules))
    for row in data:
        row_cb = []
        for col in range(len(d)):
            row_cb.append(callback(d[col][0], row[col]))
        result.append(format % tuple(row_cb))
    return "\n".join(result)


## end of http://code.activestate.com/recipes/81189/ }}}


def html_table(cur, callback=None):
    """
    cur est un cursor issu d'une requete
    callback est une fonction qui prend (rowmap,fieldname,value)
    et renvoie une representation texte
    """

    def safe_unicode(iso):
        if iso is None:
            return None
        elif isinstance(iso, str):
            return iso  # .decode()
        else:
            return iso

    def itermap(cur):
        for row in cur:
            yield dict((cur.description[idx][0], value) for idx, value in enumerate(row))

    head = "<tr>" + "".join(["<th>" + c[0] + "</th>" for c in cur.description]) + "</tr>"
    lines = ""
    if callback:
        for r in itermap(cur):
            lines = (
                lines
                + "<tr>"
                + "".join(["<td>" + str(callback(r, c[0], safe_unicode(r[c[0]]))) + "</td>" for c in cur.description])
                + "</tr>"
            )
    else:
        for r in cur:
            lines = lines + "<tr>" + "".join(["<td>" + safe_unicode(c) + "</td>" for c in r]) + "</tr>"

    return "<table border=1  cellpadding=2 cellspacing=0>%s%s</table>" % (head, lines)


def monitor_stdout(aprocess, onoutputdata, context):
    """Reads data from stdout and stderr from aprocess and return as a string
    on each chunk, call a call back onoutputdata(dataread)
    """
    assert isinstance(aprocess, subprocess.Popen)
    read_set = []
    stdout = []
    line = ""

    if aprocess.stdout:
        read_set.append(aprocess.stdout)
    if aprocess.stderr:
        read_set.append(aprocess.stderr)

    while read_set:
        try:
            rlist, wlist, xlist = select.select(read_set, [], [])
        except select.error as e:
            if e.args[0] == errno.EINTR:
                continue
            raise

        # Reads one line from stdout
        if aprocess.stdout in rlist:
            data = os.read(aprocess.stdout.fileno(), 1)
            data = data.decode(errors="ignore")
            if data == "":
                aprocess.stdout.close()
                read_set.remove(aprocess.stdout)
            while data and data not in ("\n", "\r"):
                line += data
                data = os.read(aprocess.stdout.fileno(), 1)
                data = data.decode(errors="ignore")
            if line or data in ("\n", "\r"):
                stdout.append(line)
                if onoutputdata:
                    onoutputdata(line, context)
            line = ""

        # Reads one line from stderr
        if aprocess.stderr in rlist:
            data = os.read(aprocess.stderr.fileno(), 1)
            data = data.decode(errors="ignore")
            if data == "":
                aprocess.stderr.close()
                read_set.remove(aprocess.stderr)
            while data and data not in ("\n", "\r"):
                line += data
                data = os.read(aprocess.stderr.fileno(), 1)
                data = data.decode(errors="ignore")
            if line or data in ("\n", "\r"):
                stdout.append(line)
                if onoutputdata:
                    onoutputdata(line, context)
            line = ""

    aprocess.wait()
    if line:
        stdout.append(line)
        if onoutputdata:
            onoutputdata(line, context)
    return "\n".join(stdout)


def str2bool(val):
    if not isinstance(type(val), bool):
        return val.lower() in ("yes", "true", "t", "1")


class BackupStat:
    dbpath = ""
    db = None
    logger = logging.getLogger("tisbackup")

    def __init__(self, dbpath):
        self.dbpath = dbpath
        if not os.path.isfile(self.dbpath):
            self.db = sqlite3.connect(self.dbpath)
            self.initdb()
        else:
            self.db = sqlite3.connect(self.dbpath, check_same_thread=False)
            if "'TYPE'" not in str(self.db.execute("select * from stats").description):
                self.updatedb()

    def updatedb(self):
        self.logger.debug("Update stat database")
        self.db.execute("alter table stats add column TYPE TEXT;")
        self.db.execute("update stats set TYPE='BACKUP';")
        self.db.commit()

    def initdb(self):
        assert isinstance(self.db, sqlite3.Connection)
        self.logger.debug("Initialize stat database")
        self.db.execute("""
create table stats (
  backup_name TEXT,
  server_name TEXT,
  description TEXT,
  backup_start TEXT,
  backup_end TEXT,
  backup_duration NUMERIC,
  total_files_count INT,
  written_files_count INT,
  total_bytes INT,
  written_bytes INT,
  status TEXT,
  log TEXT,
  backup_location TEXT,
  TYPE TEXT)""")
        self.db.execute("""
create index idx_stats_backup_name on stats(backup_name);""")
        self.db.execute("""
create index idx_stats_backup_location on stats(backup_location);""")
        self.db.execute("""
CREATE INDEX idx_stats_backup_name_start on stats(backup_name,backup_start);""")
        self.db.commit()

    def start(self, backup_name, server_name, TYPE, description="", backup_location=None):
        """Add in stat DB a record for the newly running backup"""
        return self.add(
            backup_name=backup_name,
            server_name=server_name,
            description=description,
            backup_start=datetime2isodate(),
            status="Running",
            TYPE=TYPE,
        )

    def finish(
        self,
        rowid,
        total_files_count=None,
        written_files_count=None,
        total_bytes=None,
        written_bytes=None,
        log=None,
        status="OK",
        backup_end=None,
        backup_duration=None,
        backup_location=None,
    ):
        """Update record in stat DB for the finished backup"""
        if not backup_end:
            backup_end = datetime2isodate()
        if backup_duration is None:
            try:
                # get duration using start of backup datetime
                backup_duration = (
                    isodate2datetime(backup_end)
                    - isodate2datetime(self.query("select backup_start from stats where rowid=?", (rowid,))[0]["backup_start"])
                ).seconds / 3600.0
            except:
                backup_duration = None

        # update stat record
        self.db.execute(
            """\
      update stats set
        total_files_count=?,written_files_count=?,total_bytes=?,written_bytes=?,log=?,status=?,backup_end=?,backup_duration=?,backup_location=?
      where
        rowid = ?
    """,
            (
                total_files_count,
                written_files_count,
                total_bytes,
                written_bytes,
                log,
                status,
                backup_end,
                backup_duration,
                backup_location,
                rowid,
            ),
        )
        self.db.commit()

    def add(
        self,
        backup_name="",
        server_name="",
        description="",
        backup_start=None,
        backup_end=None,
        backup_duration=None,
        total_files_count=None,
        written_files_count=None,
        total_bytes=None,
        written_bytes=None,
        status="draft",
        log="",
        TYPE="",
        backup_location=None,
    ):
        if not backup_start:
            backup_start = datetime2isodate()
        if not backup_end:
            backup_end = datetime2isodate()

        cur = self.db.execute(
            """\
      insert into stats (
          backup_name,
          server_name,
          description,
          backup_start,
          backup_end,
          backup_duration,
          total_files_count,
          written_files_count,
          total_bytes,
          written_bytes,
          status,
          log,
          backup_location,
          TYPE) values (?,?,?,?,?,?,?,?,?,?,?,?,?,?)
    """,
            (
                backup_name,
                server_name,
                description,
                backup_start,
                backup_end,
                backup_duration,
                total_files_count,
                written_files_count,
                total_bytes,
                written_bytes,
                status,
                log,
                backup_location,
                TYPE,
            ),
        )

        self.db.commit()
        return cur.lastrowid

    def query(self, query, args=(), one=False):
        """
        execute la requete query sur la db et renvoie un tableau de dictionnaires
        """
        cur = self.db.execute(query, args)
        rv = [dict((cur.description[idx][0], value) for idx, value in enumerate(row)) for row in cur.fetchall()]
        return (rv[0] if rv else None) if one else rv

    def last_backups(self, backup_name, count=30):
        if backup_name:
            cur = self.db.execute("select  * from stats where backup_name=? order by backup_end desc limit ?", (backup_name, count))
        else:
            cur = self.db.execute("select  * from stats order by backup_end desc limit ?", (count,))

        def fcb(fieldname, value):
            if fieldname in ("backup_start", "backup_end"):
                return time2display(isodate2datetime(value))
            elif "bytes" in fieldname:
                return convert_bytes(value)
            elif "count" in fieldname:
                return splitThousands(value, " ", ".")
            elif "backup_duration" in fieldname:
                return hours_minutes(value)
            else:
                return value

        # for r in self.query('select  * from stats where backup_name=? order by backup_end desc limit ?',(backup_name,count)):
        print((pp(cur, None, 1, fcb)))

    def fcb(self, fields, fieldname, value):
        if fieldname in ("backup_start", "backup_end"):
            return time2display(isodate2datetime(value))
        elif "bytes" in fieldname:
            return convert_bytes(value)
        elif "count" in fieldname:
            return splitThousands(value, " ", ".")
        elif "backup_duration" in fieldname:
            return hours_minutes(value)
        else:
            return value

    def as_html(self, cur):
        if cur:
            return html_table(cur, self.fcb)
        else:
            return html_table(self.db.execute("select * from stats order by backup_start asc"), self.fcb)


def ssh_exec(command, ssh=None, server_name="", remote_user="", private_key="", ssh_port=22):
    """execute command on server_name using the provided ssh connection
    or creates a new connection if ssh is not provided.
    returns (exit_code,output)

    output is the concatenation of stdout and stderr
    """
    if not ssh:
        assert server_name and remote_user and private_key
        try:
            mykey = paramiko.RSAKey.from_private_key_file(private_key)
        except paramiko.SSHException:
            # mykey = paramiko.DSSKey.from_private_key_file(private_key)
            mykey = paramiko.Ed25519Key.from_private_key_file(private_key)

        ssh = paramiko.SSHClient()
        ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
        ssh.connect(server_name, username=remote_user, pkey=mykey, port=ssh_port)

    tran = ssh.get_transport()
    chan = tran.open_session()

    # chan.set_combine_stderr(True)
    chan.get_pty()
    stdout = chan.makefile()

    chan.exec_command(command)
    stdout.flush()
    output_base = stdout.read()
    output = output_base.decode(errors="ignore").replace("'", "")
    exit_code = chan.recv_exit_status()
    return (exit_code, output)


class backup_generic(ABC):
    """Generic ancestor class for backups, not registered"""

    type = "generic"
    required_params = ["type", "backup_name", "backup_dir", "server_name", "backup_retention_time", "maximum_backup_age"]
    optional_params = ["preexec", "postexec", "description", "private_key", "remote_user", "ssh_port"]

    logger = logging.getLogger("tisbackup")
    backup_name = ""
    backup_dir = ""
    server_name = ""
    remote_user = "root"
    description = ""
    dbstat = None
    dry_run = False
    preexec = ""
    postexec = ""
    maximum_backup_age = None
    backup_retention_time = None
    verbose = False
    private_key = ""
    ssh_port = 22

    def __init__(self, backup_name, backup_dir, dbstat=None, dry_run=False):
        if not re.match(r"^[A-Za-z0-9_\-\.]*$", backup_name):
            raise Exception("The backup name %s should contain only alphanumerical characters" % backup_name)
        self.backup_name = backup_name
        self.backup_dir = backup_dir

        self.dbstat = dbstat
        assert isinstance(self.dbstat, BackupStat) or self.dbstat is None

        if not os.path.isdir(self.backup_dir):
            os.makedirs(self.backup_dir)

        self.dry_run = dry_run

    @classmethod
    def get_help(cls):
        return """\
%(type)s : %(desc)s
  Required params : %(required)s
  Optional params : %(optional)s
""" % {"type": cls.type, "desc": cls.__doc__, "required": ",".join(cls.required_params), "optional": ",".join(cls.optional_params)}

    def check_required_params(self):
        for name in self.required_params:
            if not hasattr(self, name) or not getattr(self, name):
                raise Exception("[%s] Config Attribute %s is required" % (self.backup_name, name))
        if (self.preexec or self.postexec) and (not self.private_key or not self.remote_user):
            raise Exception("[%s] remote_user and private_key file required if preexec or postexec is used" % self.backup_name)

    def read_config(self, iniconf):
        assert isinstance(iniconf, ConfigParser)
        allowed_params = self.required_params + self.optional_params
        for name, value in iniconf.items(self.backup_name):
            if name not in allowed_params:
                self.logger.critical('[%s] Invalid param name "%s"', self.backup_name, name)
                raise Exception('[%s] Invalid param name "%s"', self.backup_name, name)
            self.logger.debug("[%s] reading param %s = %s ", self.backup_name, name, value)
            setattr(self, name, value)

        # if retention (in days) is not defined at section level, get default global one.
        if not self.backup_retention_time:
            self.backup_retention_time = iniconf.getint("global", "backup_retention_time")

        # for nagios, if maximum last backup age (in hours) is not defined at section level, get default global one.
        if not self.maximum_backup_age:
            self.maximum_backup_age = iniconf.getint("global", "maximum_backup_age")

        self.ssh_port = int(self.ssh_port)
        self.backup_retention_time = int(self.backup_retention_time)
        self.maximum_backup_age = int(self.maximum_backup_age)

        self.check_required_params()

    def do_preexec(self, stats):
        self.logger.info("[%s] executing preexec %s ", self.backup_name, self.preexec)
        try:
            mykey = paramiko.RSAKey.from_private_key_file(self.private_key)
        except paramiko.SSHException:
            mykey = paramiko.DSSKey.from_private_key_file(self.private_key)

        ssh = paramiko.SSHClient()
        ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
        ssh.connect(self.server_name, username=self.remote_user, pkey=mykey)
        tran = ssh.get_transport()
        chan = tran.open_session()

        # chan.set_combine_stderr(True)
        chan.get_pty()
        stdout = chan.makefile()

        if not self.dry_run:
            chan.exec_command(self.preexec)
            output = stdout.read()
            exit_code = chan.recv_exit_status()
            self.logger.info('[%s] preexec exit code : "%i", output : %s', self.backup_name, exit_code, output)
            return exit_code
        else:
            return 0

    def do_postexec(self, stats):
        self.logger.info("[%s] executing postexec %s ", self.backup_name, self.postexec)
        try:
            mykey = paramiko.RSAKey.from_private_key_file(self.private_key)
        except paramiko.SSHException:
            mykey = paramiko.DSSKey.from_private_key_file(self.private_key)

        ssh = paramiko.SSHClient()
        ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
        ssh.connect(self.server_name, username=self.remote_user, pkey=mykey)
        tran = ssh.get_transport()
        chan = tran.open_session()

        # chan.set_combine_stderr(True)
        chan.get_pty()
        stdout = chan.makefile()

        if not self.dry_run:
            chan.exec_command(self.postexec)
            output = stdout.read()
            exit_code = chan.recv_exit_status()
            self.logger.info('[%s] postexec exit code : "%i", output : %s', self.backup_name, exit_code, output)
            return exit_code
        else:
            return 0

    def do_backup(self, stats):
        """stats dict with keys : total_files_count,written_files_count,total_bytes,written_bytes"""
        pass

    def check_params_connections(self):
        """Perform a dry run trying to connect without actually doing backup"""
        self.check_required_params()

    def process_backup(self):
        """Process the backup.
        launch
         - do_preexec
         - do_backup
         - do_postexec

        returns a dict for stats
        """
        self.logger.info("[%s] ######### Starting backup", self.backup_name)

        starttime = time.time()
        self.backup_start_date = datetime.datetime.now().strftime("%Y%m%d-%Hh%Mm%S")

        if not self.dry_run and self.dbstat:
            stat_rowid = self.dbstat.start(backup_name=self.backup_name, server_name=self.server_name, TYPE="BACKUP")
        else:
            stat_rowid = None

        try:
            stats = {}
            stats["total_files_count"] = 0
            stats["written_files_count"] = 0
            stats["total_bytes"] = 0
            stats["written_bytes"] = 0
            stats["log"] = ""
            stats["status"] = "Running"
            stats["backup_location"] = None

            if self.preexec.strip():
                exit_code = self.do_preexec(stats)
                if exit_code != 0:
                    raise Exception('Preexec "%s" failed with exit code "%i"' % (self.preexec, exit_code))

            self.do_backup(stats)

            if self.postexec.strip():
                exit_code = self.do_postexec(stats)
                if exit_code != 0:
                    raise Exception('Postexec "%s" failed with exit code "%i"' % (self.postexec, exit_code))

            endtime = time.time()
            duration = (endtime - starttime) / 3600.0
            if not self.dry_run and self.dbstat:
                self.dbstat.finish(
                    stat_rowid,
                    backup_end=datetime2isodate(datetime.datetime.now()),
                    backup_duration=duration,
                    total_files_count=stats["total_files_count"],
                    written_files_count=stats["written_files_count"],
                    total_bytes=stats["total_bytes"],
                    written_bytes=stats["written_bytes"],
                    status=stats["status"],
                    log=stats["log"],
                    backup_location=stats["backup_location"],
                )

            self.logger.info("[%s] ######### Backup finished : %s", self.backup_name, stats["log"])
            return stats

        except BaseException as e:
            stats["status"] = "ERROR"
            stats["log"] = str(e)
            endtime = time.time()
            duration = (endtime - starttime) / 3600.0
            if not self.dry_run and self.dbstat:
                self.dbstat.finish(
                    stat_rowid,
                    backup_end=datetime2isodate(datetime.datetime.now()),
                    backup_duration=duration,
                    total_files_count=stats["total_files_count"],
                    written_files_count=stats["written_files_count"],
                    total_bytes=stats["total_bytes"],
                    written_bytes=stats["written_bytes"],
                    status=stats["status"],
                    log=stats["log"],
                    backup_location=stats["backup_location"],
                )

            self.logger.error("[%s] ######### Backup finished with ERROR: %s", self.backup_name, stats["log"])
            raise

    def checknagios(self):
        """
        Returns a tuple (nagiosstatus,message) for the current backup_name
        Read status from dbstat database
        """
        if not self.dbstat:
            self.logger.warn("[%s] checknagios : no database provided", self.backup_name)
            return ("No database provided", nagiosStateUnknown)
        else:
            self.logger.debug(
                '[%s] checknagios : sql query "%s" %s',
                self.backup_name,
                "select status, backup_end, log from stats where TYPE='BACKUP' AND backup_name=? order by backup_end desc limit 30",
                self.backup_name,
            )
            q = self.dbstat.query(
                "select status, backup_start, backup_end, log, backup_location, total_bytes from stats where TYPE='BACKUP' AND backup_name=? order by backup_start desc limit 30",
                (self.backup_name,),
            )
            if not q:
                self.logger.debug("[%s] checknagios : no result from query", self.backup_name)
                return (nagiosStateCritical, "CRITICAL : No backup found for %s in database" % self.backup_name)
            else:
                mindate = datetime2isodate((datetime.datetime.now() - datetime.timedelta(hours=self.maximum_backup_age)))
                self.logger.debug("[%s] checknagios : looking for most recent OK not older than %s", self.backup_name, mindate)
                for b in q:
                    if b["backup_end"] >= mindate and b["status"] == "OK":
                        # check if backup actually exists on registered backup location and is newer than backup start date
                        if b["total_bytes"] == 0:
                            return (nagiosStateWarning, "WARNING : No data to backup was found for %s" % (self.backup_name,))

                        if not b["backup_location"]:
                            return (
                                nagiosStateWarning,
                                "WARNING : No Backup location found for %s finished on (%s) %s"
                                % (self.backup_name, isodate2datetime(b["backup_end"]), b["log"]),
                            )

                        if os.path.isfile(b["backup_location"]):
                            backup_actual_date = datetime.datetime.fromtimestamp(os.stat(b["backup_location"]).st_ctime)
                            if backup_actual_date + datetime.timedelta(hours=1) > isodate2datetime(b["backup_start"]):
                                return (
                                    nagiosStateOk,
                                    "OK Backup %s (%s), %s" % (self.backup_name, isodate2datetime(b["backup_end"]), b["log"]),
                                )
                            else:
                                return (
                                    nagiosStateCritical,
                                    "CRITICAL Backup %s (%s), %s seems older than start of backup"
                                    % (self.backup_name, isodate2datetime(b["backup_end"]), b["log"]),
                                )
                        elif os.path.isdir(b["backup_location"]):
                            return (
                                nagiosStateOk,
                                "OK Backup %s (%s), %s" % (self.backup_name, isodate2datetime(b["backup_end"]), b["log"]),
                            )
                        elif self.type == "copy-vm-xcp":
                            return (
                                nagiosStateOk,
                                "OK Backup %s (%s), %s" % (self.backup_name, isodate2datetime(b["backup_end"]), b["log"]),
                            )
                        else:
                            return (
                                nagiosStateCritical,
                                "CRITICAL Backup %s (%s), %s has disapeared from backup location %s"
                                % (self.backup_name, isodate2datetime(b["backup_end"]), b["log"], b["backup_location"]),
                            )

                self.logger.debug(
                    "[%s] checknagios : looking for most recent Warning or Running not older than %s", self.backup_name, mindate
                )
                for b in q:
                    if b["backup_end"] >= mindate and b["status"] in ("Warning", "Running"):
                        return (nagiosStateWarning, "WARNING : Backup %s still running or warning. %s" % (self.backup_name, b["log"]))

                self.logger.debug("[%s] checknagios : No Ok or warning recent backup found", self.backup_name)
                return (nagiosStateCritical, "CRITICAL : No recent backup for %s" % self.backup_name)

    def cleanup_backup(self):
        """Removes obsolete backups (older than backup_retention_time)"""
        mindate = datetime2isodate((dateof(datetime.datetime.now()) - datetime.timedelta(days=self.backup_retention_time)))
        # check if there is at least 1 "OK" backup left after cleanup :
        ok_backups = self.dbstat.query(
            'select backup_location from stats where TYPE="BACKUP" and backup_name=? and backup_start>=? and status="OK" order by backup_start desc',
            (self.backup_name, mindate),
        )
        removed = []
        if ok_backups and os.path.exists(ok_backups[0]["backup_location"]):
            records = self.dbstat.query(
                'select status, backup_start, backup_end, log, backup_location from stats where backup_name=? and backup_start<? and backup_location is not null and TYPE="BACKUP" order by backup_start',
                (self.backup_name, mindate),
            )
            if records:
                for oldbackup_location in [rec["backup_location"] for rec in records if rec["backup_location"]]:
                    try:
                        if os.path.isdir(oldbackup_location) and self.backup_dir in oldbackup_location:
                            self.logger.info('[%s] removing directory "%s"', self.backup_name, oldbackup_location)
                            if not self.dry_run:
                                if self.type == "rsync+btrfs+ssh" or self.type == "rsync+btrfs":
                                    cmd = "/bin/btrfs subvolume delete %s" % oldbackup_location
                                    process = subprocess.Popen(
                                        cmd, shell=True, stdout=subprocess.PIPE, stderr=subprocess.STDOUT, close_fds=True
                                    )
                                    log = monitor_stdout(process, "", self)
                                    returncode = process.returncode
                                    if returncode != 0:
                                        self.logger.error("[" + self.backup_name + "] shell program exited with error code: %s" % log)
                                        raise Exception(
                                            "[" + self.backup_name + "] shell program exited with error code " + str(returncode), cmd
                                        )
                                    else:
                                        self.logger.info(
                                            "[" + self.backup_name + "] deleting snapshot volume: %s" % oldbackup_location.encode("ascii")
                                        )
                                else:
                                    shutil.rmtree(oldbackup_location.encode("ascii"))
                        if os.path.isfile(oldbackup_location) and self.backup_dir in oldbackup_location:
                            self.logger.debug('[%s] removing file "%s"', self.backup_name, oldbackup_location)
                            if not self.dry_run:
                                os.remove(oldbackup_location)
                        self.logger.debug('Cleanup_backup : Removing records from DB : [%s]-"%s"', self.backup_name, oldbackup_location)
                        if not self.dry_run:
                            self.dbstat.db.execute(
                                'update stats set TYPE="CLEAN" where backup_name=? and backup_location=?',
                                (self.backup_name, oldbackup_location),
                            )
                            self.dbstat.db.commit()
                    except BaseException as e:
                        self.logger.error('cleanup_backup : Unable to remove directory/file "%s". Error %s', oldbackup_location, e)
                    removed.append((self.backup_name, oldbackup_location))
            else:
                self.logger.debug("[%s] cleanup : no result for query", self.backup_name)
        else:
            self.logger.info("Nothing to do because we want to keep at least one OK backup after cleaning")

        self.logger.info(
            "[%s] Cleanup finished : removed : %s", self.backup_name, ",".join([('[%s]-"%s"') % r for r in removed]) or "Nothing"
        )
        return removed

    @abstractmethod
    def register_existingbackups(self):
        pass
        # """scan existing backups and insert stats in database"""
        # registered = [b['backup_location'] for b in self.dbstat.query('select distinct backup_location from stats where backup_name=?',[self.backup_name])]
        # raise Exception('Abstract method')

    def export_latestbackup(self, destdir):
        """Copy (rsync) latest OK backup to external storage located at locally mounted "destdir" """
        stats = {}
        stats["total_files_count"] = 0
        stats["written_files_count"] = 0
        stats["total_bytes"] = 0
        stats["written_bytes"] = 0
        stats["log"] = ""
        stats["status"] = "Running"
        if not self.dbstat:
            self.logger.critical("[%s] export_latestbackup : no database provided", self.backup_name)
            raise Exception("No database")
        else:
            latest_sql = """\
              select status, backup_start, backup_end, log, backup_location, total_bytes
              from stats
              where backup_name=? and status='OK' and TYPE='BACKUP'
              order by backup_start desc limit 30"""
            self.logger.debug('[%s] export_latestbackup : sql query "%s" %s', self.backup_name, latest_sql, self.backup_name)
            q = self.dbstat.query(latest_sql, (self.backup_name,))
            if not q:
                self.logger.debug("[%s] export_latestbackup : no result from query", self.backup_name)
                raise Exception("No OK backup found for %s in database" % self.backup_name)
            else:
                latest = q[0]
                backup_source = latest["backup_location"]
                backup_dest = os.path.join(os.path.abspath(destdir), self.backup_name)
                if not os.path.exists(backup_source):
                    raise Exception("Backup source %s doesn't exists" % backup_source)

                # ensure there is a slash at end
                if os.path.isdir(backup_source) and backup_source[-1] != "/":
                    backup_source += "/"
                    if backup_dest[-1] != "/":
                        backup_dest += "/"

                if not os.path.isdir(backup_dest):
                    os.makedirs(backup_dest)

                options = ["-aP", "--stats", "--delete-excluded", "--numeric-ids", "--delete-after"]
                if self.logger.level:
                    options.append("-P")

                if self.dry_run:
                    options.append("-d")

                options_params = " ".join(options)

                cmd = "/usr/bin/rsync %s %s %s 2>&1" % (options_params, backup_source, backup_dest)
                self.logger.debug("[%s] rsync : %s", self.backup_name, cmd)

                if not self.dry_run:
                    self.line = ""
                    starttime = time.time()
                    stat_rowid = self.dbstat.start(backup_name=self.backup_name, server_name=self.server_name, TYPE="EXPORT")

                    process = subprocess.Popen(cmd, shell=True, stdout=subprocess.PIPE, stderr=subprocess.STDOUT, close_fds=True)

                    def ondata(data, context):
                        if context.verbose:
                            print(data)
                        context.logger.debug(data)

                    log = monitor_stdout(process, ondata, self)

                    for l in log.splitlines():
                        if l.startswith("Number of files:"):
                            stats["total_files_count"] += int(re.findall("[0-9]+", l.split(":")[1])[0])
                        if l.startswith("Number of files transferred:"):
                            stats["written_files_count"] += int(l.split(":")[1])
                        if l.startswith("Total file size:"):
                            stats["total_bytes"] += float(l.replace(",", "").split(":")[1].split()[0])
                        if l.startswith("Total transferred file size:"):
                            stats["written_bytes"] += float(l.replace(",", "").split(":")[1].split()[0])
                    returncode = process.returncode
                    ## deal with exit code 24 (file vanished)
                    if returncode == 24:
                        self.logger.warning("[" + self.backup_name + "] Note: some files vanished before transfer")
                    elif returncode == 23:
                        self.logger.warning("[" + self.backup_name + "] unable so set uid on some files")
                    elif returncode != 0:
                        self.logger.error("[" + self.backup_name + "] shell program exited with error code ")
                        raise Exception("[" + self.backup_name + "] shell program exited with error code " + str(returncode), cmd)
                else:
                    print(cmd)

                stats["status"] = "OK"
                self.logger.info(
                    "export backup from %s to %s OK, %d bytes written for %d changed files"
                    % (backup_source, backup_dest, stats["written_bytes"], stats["written_files_count"])
                )

                endtime = time.time()
                duration = (endtime - starttime) / 3600.0
                if not self.dry_run and self.dbstat:
                    self.dbstat.finish(
                        stat_rowid,
                        backup_end=datetime2isodate(datetime.datetime.now()),
                        backup_duration=duration,
                        total_files_count=stats["total_files_count"],
                        written_files_count=stats["written_files_count"],
                        total_bytes=stats["total_bytes"],
                        written_bytes=stats["written_bytes"],
                        status=stats["status"],
                        log=stats["log"],
                        backup_location=backup_dest,
                    )
                return stats


if __name__ == "__main__":
    logger = logging.getLogger("tisbackup")
    logger.setLevel(logging.DEBUG)
    formatter = logging.Formatter("%(asctime)s %(levelname)s %(message)s")
    handler = logging.StreamHandler()
    handler.setFormatter(formatter)
    logger.addHandler(handler)
    dbstat = BackupStat("/backup/data/log/tisbackup.sqlite")