#!/usr/bin/env python
#
# Expire old snapshots

import sys, commands, datetime, os, string

pbc = os.getenv('PORTBUILD_CHECKOUT') \
    if os.getenv('PORTBUILD_CHECKOUT') else "/a/portbuild"

sys.path.insert(0, '%s/admin/lib/python' % pbc)

from freebsd import *
from freebsd_config import *
import zfs

CONFIG_SUBDIR="conf"
CONFIG_FILENAME="server.conf"

ENABLED	=	True
VERBOSE=	True

expirelist={}

now = datetime.datetime.now()
print "zexpire: starting at " + now.ctime()

config = getConfig( pbc, CONFIG_SUBDIR, CONFIG_FILENAME )
ZFS_VOLUME = config.get( 'ZFS_VOLUME' )
if not ZFS_VOLUME:
    print "you must define ZFS_VOLUME"
    sys.exit( 1 )
ZFS_MOUNTPOINT = config.get( 'ZFS_MOUNTPOINT' )
if not ZFS_MOUNTPOINT:
    print "you must define ZFS_MOUNTPOINT"
    sys.exit( 1 )
PORTBUILD_DIRECTORY = config.get( 'PORTBUILD_DIRECTORY' )
if not PORTBUILD_DIRECTORY:
    print "you must define PORTBUILD_DIRECTORY"
    sys.exit( 1 )
portbuild_directory = os.path.join( ZFS_VOLUME, PORTBUILD_DIRECTORY )
SNAP_DIRECTORY = config.get( 'SNAP_DIRECTORY' )
if not SNAP_DIRECTORY:
    print "you must define SNAP_DIRECTORY"
    sys.exit( 1 )
snap_directory = os.path.join( ZFS_VOLUME, SNAP_DIRECTORY )
snap_mountpoint = os.path.join( ZFS_MOUNTPOINT, SNAP_DIRECTORY )
SUPPORTED_ARCHS = config.get( 'SUPPORTED_ARCHS' )
if not SUPPORTED_ARCHS:
    print "you must define SUPPORTED_ARCHS"
    sys.exit( 1 )
supported_archs = string.split( SUPPORTED_ARCHS )
ZFS_DEFAULT_EXPIRATION = config.get( 'ZFS_DEFAULT_EXPIRATION' )
if not ZFS_DEFAULT_EXPIRATION:
    print "you must define ZFS_DEFAULT_EXPIRATION"
    sys.exit( 1 )
ZFS_SNAPSHOT_EXPIRATION = config.get( 'ZFS_SNAPSHOT_EXPIRATION' )
if not ZFS_SNAPSHOT_EXPIRATION:
    print "you must define ZFS_SNAPSHOT_EXPIRATION"
    sys.exit( 1 )

expirelist[ ZFS_VOLUME ] = ZFS_DEFAULT_EXPIRATION
expirelist[ portbuild_directory ] = ZFS_DEFAULT_EXPIRATION
for arch in supported_archs:
    expirelist[ os.path.join( portbuild_directory, arch ) ] = ZFS_DEFAULT_EXPIRATION
expirelist[ snap_directory ] = ZFS_SNAPSHOT_EXPIRATION
try:
    snapdirs = os.listdir( snap_mountpoint )
    for snapdir in snapdirs:
        subdir = os.path.join( snap_mountpoint, snapdir )
        tmp = os.path.join( snap_directory, snapdir )
        expirelist[ tmp ] = ZFS_SNAPSHOT_EXPIRATION
        try:
            snapsubdirs = os.listdir( subdir )
            for snapsubdir in snapsubdirs:
                expirelist[ os.path.join( tmp, snapsubdir ) ] = ZFS_SNAPSHOT_EXPIRATION
        except:
            pass
except:
    pass

keys = expirelist.keys()
keys.sort()
for key in keys:
    fs = key
    maxage = 2
    try:
        maxage = int( expirelist[ key ] )
    except:
        pass

    print

    if VERBOSE:
        print "fs: " + str(fs)
    try:
        snapdata = zfs.getallsnaps(fs)
        if VERBOSE:
            print "snapdata: " + str(snapdata)
    except zfs.NoSuchFS:
        print "zexpire: no such fs %s, skipping" % fs
        continue

    snaps = (i[0] for i in snapdata)

    for snap in snaps:
        try:
            snapdate = datetime.datetime.strptime(snap, "%Y%m%d%H%M")
        except ValueError:
            try:
                snapdate = datetime.datetime.strptime(snap, "%Y%m%d%H%M%S")
            except ValueError:
                print "zexpire: don't know what to do with snap `" + snap + "'"
                continue

        if VERBOSE:
            print "zexpire: examining snapshot %s@%s" % (fs, snap)
        if (now - snapdate) > datetime.timedelta(days=maxage):
            print "zexpire: snapshot %s@%s too old, attempting zfs destroy" % (fs, snap)
            if ENABLED:
                (err, out) = commands.getstatusoutput("zfs destroy %s@%s" % (fs,snap))

                if err:
                    print "zexpire: error deleting snapshot", out

then = datetime.datetime.now()
print
print "zexpire: ending at " + then.ctime()