src/tashi/clustermanager/data/pickled.py

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# to you under the Apache License, Version 2.0 (the
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# 
#   http://www.apache.org/licenses/LICENSE-2.0
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import logging
import cPickle
import os
import threading
from tashi.rpycservices.rpyctypes import Instance, Host
from tashi.clustermanager.data import FromConfig, DataInterface

class Pickled(FromConfig):
	def __init__(self, config):
		DataInterface.__init__(self, config)
		self.log = logging.getLogger(__name__)
		self.file = self.config.get("Pickled", "file")
		self.locks = {}
		self.lockNames = {}
		self.instanceLock = threading.Lock()
		self.lockNames[self.instanceLock] = "instanceLock"
		self.instanceIdLock = threading.Lock()
		self.lockNames[self.instanceIdLock] = "instanceIdLock"
		self.maxInstanceId = 1
		self.hostLock = threading.Lock()
		self.hostLocks = {}
		self.idLock = threading.Lock()
		self.load()
	
	def cleanInstances(self):
		ci = {}
		for ignore, i in self.instances.items():
			i2 = Instance(d=i.__dict__)
			ci[i2.id] = i2
		return ci
	
	def cleanHosts(self):
		ch = {}
		for ignore, h in self.hosts.items():
			h2 = Host(d=h.__dict__)
			ch[h2.id] = h2
		return ch
	
	def save(self):
		filename = self.file
		# XXXstroucki could be better
		tempfile = "%s.new" % filename

		file = open(tempfile, "w")
		cPickle.dump((self.cleanHosts(), self.cleanInstances(), self.networks, self.users), file)
		file.close()
		os.rename(tempfile, filename)

	def load(self):
		if (os.access(self.file, os.F_OK)):
			file = open(self.file, "r")
			(hosts, instances, networks, users) = cPickle.load(file)
			file.close()
		else:
			(hosts, instances, networks, users) = ({}, {}, {}, {})
		self.hosts = hosts
		self.instances = instances
		self.networks = networks
		self.users = users
		for ignore, i in self.instances.items():
			if (i.id >= self.maxInstanceId):
				self.maxInstanceId = i.id + 1
			i._lock = threading.Lock()
			self.lockNames[i._lock] = "i%d" % (i.id)
		for ignore, h in self.hosts.items():
			h._lock = threading.Lock()
			self.lockNames[h._lock] = "h%d" % (h.id)