I'm trying to implement a file server using the code below. However
the locking doesn't work. I can delete while put'ing a file.
Anyone got an idea about why?
best regards,
seb
#! /usr/bin/env python
import Pyro.core, Pyro.naming
from Pyro.errors import PyroError, NamingError
import sys
import urllib
import os
import fcntl
class fileServer(Pyro.core.ObjBase):
basePath = "/home/snot/diku/dist/opg2/files_to_serve"
def __init__(self):
Pyro.core.ObjBase.__init__(self)
self.basePath = self.basePath.strip("..")
if not os.path.isdir(self.basePath) or
os.path.islink(self.basePath):
raise "invalid path"
def get(self, uri):
f = open(self.basePath + uri, 'r+')
fcntl.flock(f, fcntl.LOCK_SH)
data = f.read()
fcntl.flock(f, fcntl.LOCK_UN)
f.close()
return data
def put(self, uri, payload):
f = open(self.basePath + urllib.unquote_plus(uri), 'w')
fcntl.flock(f, fcntl.LOCK_EX)
f.truncate()
f.write(payload)
fcntl.flock(f, fcntl.LOCK_UN)
f.close()
def delete(self, uri):
f = open(self.basePath + urllib.unquote_plus(uri), 'w')
fcntl.flock(f, fcntl.LOCK_EX)
os.unlink(self.basePath + uri)
fcntl.flock(f, fcntl.LOCK_UN)
f.close()
try:
Pyro.core.initServer()
daemon = Pyro.core.Daemon()
locator = Pyro.naming.NameServerLocator()
print 'Searching for Name Server...'
try:
ns = locator.getNS()
except Pyro.errors.PyroError, message:
print message
sys.exit(1)
daemon.useNameServer(ns)
try:
ns.unregister("fileServer")
except NamingError:
pass
uri = daemon.connect(fileServer(), "fileServer")
print "The daemon runs on port:", daemon.port
print "The object's uri is:", uri
daemon.requestLoop()
except KeyboardInterrupt:
ns.unregister("fileServer")
print "ctrl + c pressed"
