Add config file locking

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Disassembler 2018-10-28 18:19:45 +01:00
parent cb0d0012c9
commit f675996e60
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@ -1,18 +1,25 @@
# -*- coding: utf-8 -*- # -*- coding: utf-8 -*-
import fcntl
import json import json
CONF_FILE = '/srv/vm/config.json' CONF_FILE = '/srv/vm/config.json'
# Locking is needed in order to prevent race conditions in WSGI threads
LOCK_FILE = '/srv/vm/config.lock'
class Config: class Config:
def __init__(self): def __init__(self):
self.load() self.load()
def load(self): def load(self):
with open(LOCK_FILE, 'w') as l:
fcntl.flock(l, fcntl.LOCK_EX)
with open(CONF_FILE, 'r') as f: with open(CONF_FILE, 'r') as f:
self.data = json.load(f) self.data = json.load(f)
def save(self): def save(self):
with open(LOCK_FILE, 'w') as l:
fcntl.flock(l, fcntl.LOCK_EX)
with open(CONF_FILE, 'w') as f: with open(CONF_FILE, 'w') as f:
json.dump(self.data, f, sort_keys=True, indent=4) json.dump(self.data, f, sort_keys=True, indent=4)