61 lines
2.0 KiB
Python
61 lines
2.0 KiB
Python
|
#!/usr/bin/env python3
|
||
|
|
|
||
|
|
# zkhandler.py - Secure versioned ZooKeeper updates
|
||
|
|
# Part of the Parallel Virtual Cluster (PVC) system
|
||
|
|
#
|
||
|
|
# Copyright (C) 2018 Joshua M. Boniface <joshua@boniface.me>
|
||
|
|
#
|
||
|
|
# This program 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.
|
||
|
|
#
|
||
|
|
# This program 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 this program. If not, see <https://www.gnu.org/licenses/>.
|
||
|
|
#
|
||
|
|
###############################################################################
|
||
|
|
|
||
|
|
import kazoo.client
|
||
|
|
import lib.ansiiprint
|
||
|
|
|
||
|
|
# Child list function
|
||
|
|
def listchildren(zk_conn, key):
|
||
|
|
children = zk_conn.get_children(key)
|
||
|
|
return children
|
||
|
|
|
||
|
|
# Data read function
|
||
|
|
def readdata(zk_conn, key):
|
||
|
|
data_raw = zk_conn.get(key)
|
||
|
|
data = data_raw[0].decode('ascii')
|
||
|
|
meta = data_raw[1]
|
||
|
|
return data
|
||
|
|
|
||
|
|
# Data write function
|
||
|
|
def writedata(zk_conn, kv):
|
||
|
|
# Get the current version; we base this off the first key (ordering in multi-key calls is irrelevant)
|
||
|
|
first_key = list(kv.keys())[0]
|
||
|
|
orig_data_raw = zk_conn.get(first_key)
|
||
|
|
meta = orig_data_raw[1]
|
||
|
|
if meta == None:
|
||
|
|
ansiiprint.echo('Zookeeper key "{}" does not exist'.format(first_key), '', 'e')
|
||
|
|
return 1
|
||
|
|
|
||
|
|
version = meta.version
|
||
|
|
new_version = version + 1
|
||
|
|
zk_transaction = zk_conn.transaction()
|
||
|
|
for key, data in kv.items():
|
||
|
|
zk_transaction.set_data(key, data.encode('ascii'))
|
||
|
|
try:
|
||
|
|
zk_transaction.check(first_key, new_version)
|
||
|
|
except TypeError:
|
||
|
|
ansiiprint.echo('Zookeeper key "{}" does not match expected version'.format(first_key), '', 'e')
|
||
|
|
return 1
|
||
|
|
zk_transaction.commit()
|
||
|
|
return 0
|
||
|
|
|