#############################################################################
#
# $Id: remote.py,v 1.6.2.2 2008/06/28 21:45:29 irmen Exp $
# simple Pyro connection module, originally written by John Wiegley
#
# This is part of "Pyro" - Python Remote Objects
# which is (c) Irmen de Jong - irmen@users.sourceforge.net
#
#############################################################################
import UserDict
import exceptions
import os
import re
import signal
import socket
import sys
import time
import types
import Pyro.errors
import Pyro.naming
import Pyro.core
import Pyro.util
from Pyro.protocol import ProtocolError
true, false = 1, 0
copy_types = false
verbose = false
pyro_nameserver = None
pyro_daemon = None
client_initialized = false
server_initialized = false
daemon_host = ''
daemon_port = 0
daemon_objects = []
daemon_types = []
def tb_info(tb):
codename = tb.tb_frame.f_code.co_filename
lineno = tb.tb_lineno
if not (codename == '<string>' or codename.find(".py") > 0):
lineno = lineno - 2
return lineno, codename
def canonize(e_type, e_val, e_traceback):
"Turn the exception into a textual representation."
# find the last traceback:
tb = e_traceback
lineno, codename = tb_info(tb)
lines = [ "%s %s" % (codename, lineno) ]
found = None
if tb.tb_frame.f_code.co_filename[0] == '<':
found = tb
while tb.tb_next:
tb = tb.tb_next
if tb.tb_frame.f_code.co_filename[0] == '<':
found = tb
lineno, codename = tb_info(tb)
lines.append("%s %s" % (codename, lineno))
if found:
tb = found
lineno, codename = tb_info(tb)
if codename == '<string>':
lines.insert(0, "%s in command: %s" % (e_type, e_val))
elif codename.find(".py") > 0 and e_type == "SyntaxError":
lines.insert(0, "%s in: %s" % (e_type, e_val))
else:
lines.insert(0, "%s in line %s of %s: %s" %
(e_type, lineno, codename, e_val))
return lines
def exception_text():
return sys.exc_value
def format_exception():
return canonize(*sys.exc_info())
def register_type(t):
"""Whenever type T goes in or out, wrap/unwrap the type so that
the user is always interacting with the server object, or the
server interacts with the object directly."""
if t not in daemon_types:
daemon_types.append(t)
def unregister_objects():
if pyro_daemon:
global daemon_objects
for obj in daemon_objects:
try: pyro_daemon.disconnect(obj)
except: pass
daemon_objects = []
sys.exitfunc = unregister_objects
def host_ipaddr(interface = None):
if sys.platform == "win32":
return socket.gethostbyname(socket.gethostname())
cmd = "/sbin/ifconfig"
if interface:
cmd = '%s %s' % (cmd, interface)
fd = os.popen(cmd)
this_host = None
interfaces = {}
name = None
for line in fd.readlines():
match = re.match("(\S+)", line)
if match: name = match.group(1)
match = re.search("inet addr:(\S+)", line)
if match:
addr = match.group(1)
if name:
interfaces[name] = addr
if interfaces.has_key(interface):
this_host = interfaces[interface]
else:
for name, addr in interfaces.items():
if re.match("ppp", name):
this_host = addr
break
elif re.match("eth", name):
this_host = addr
fd.close()
return this_host or socket.gethostbyname(socket.gethostname())
def find_nameserver(hostname = None, portnum = None):
if hostname and hostname.find('://') > 0:
URI = Pyro.core.PyroURI(hostname)
ns = Pyro.naming.NameServerProxy(URI)
else:
try:
if verbose:
print 'Searching for Naming Service on %s:%d...' % \
(hostname or 'BROADCAST',
portnum or Pyro.config.PYRO_NS_BC_PORT)
locator = Pyro.naming.NameServerLocator()
ns = locator.getNS(host = hostname, port = portnum)
except (Pyro.core.PyroError, socket.error), x:
localhost = socket.gethostbyname('localhost')
if verbose:
print "Error:", x
print """
Naming Service not found with broadcast.
Trying local host""", localhost, '...',
ns = locator.getNS(host = localhost, port = portnum)
if verbose: print 'Naming Service found at', ns.URI
return ns
class Error(Exception): pass
class ObjBase(Pyro.core.ObjBase):
"""This extension of Pyro.core.ObjBase makes sure that any values
that get returned to the caller which are of a significant type,
get wrapped first in proxies.
Likewise, if a proxy class comes back to us, and it's in regard to
an object native to this server, unwrap it."""
def __nonzero__(self): return 1
def Pyro_dyncall(self, method, flags, args):
try:
base = Pyro.core.ObjBase.Pyro_dyncall
result = wrap(base(self, method, flags, unwrap(args)))
except:
result = Error('\n'.join(format_exception()))
return result
def _r_ga(self, attr):
return wrap(Pyro.core.ObjBase._r_ga(self, attr))
def _r_sa(self, attr, value):
Pyro.core.ObjBase._r_sa(self, attr, unwrap(value))
class Nameserver:
"""This helper class allows the server to use Pyro's naming
service for publishing certain objects by name. It integrates
better with remote.py, than Pyro.naming.NameServer does."""
def __init__(self, ns, ns_port):
self.ns = ns
self.ns_port = ns_port
def __cmp__(self, other):
return self.ns == other.ns and self.ns_port == other.ns_port
def __str__(self):
if self.ns_port:
return "%s:%s" % (self.ns, self.ns_port)
return self.ns
def resolve(self, name):
return get_remote_object(name, self.ns, self.ns_port)
def register(self, name, object):
return provide_local_object(object, name, self.ns, self.ns_port)
def unregister(self, object):
for obj in daemon_objects[:]:
if obj.delegate is object:
pyro_daemon.disconnect(obj)
daemon_objects.remove(obj)
class DynamicProxy(Pyro.core.DynamicProxyWithAttrs):
"""This version of the proxy just wraps args before making
external calls."""
def __nonzero__(self):
return true
def _invokePYRO(self, *vargs, **kargs):
result = unwrap(apply(Pyro.core.DynamicProxyWithAttrs._invokePYRO,
tuple([self] + wrap(list(vargs))), wrap(kargs)))
if type(result) is types.InstanceType and \
isinstance(result, Error) or \
isinstance(result, Pyro.errors.PyroError) or \
isinstance(result, ProtocolError):
msg = str(result)
type_name = msg[: msg.find(' ')]
if type_name == 'exceptions.IndexError':
try:
real_type = eval(type_name)
msg = msg.split('\n')[0]
result = real_type(msg[msg.find(':') + 2 :])
except:
pass
raise result
else:
return result
def unwrap(value):
t = type(value)
if t is types.InstanceType and isinstance(value, DynamicProxy):
if pyro_daemon:
try:
return pyro_daemon.getLocalObject(value.objectID)
except KeyError:
pass
return value
elif t is types.ListType:
for i in range(len(value)):
value[i] = unwrap(value[i])
elif t is types.TupleType:
value = list(value)
for i in range(len(value)):
value[i] = unwrap(value[i])
return tuple(value)
elif t is types.DictType:
for k, v in value.items():
value[k] = unwrap(v)
return value
def wrap(value):
"""Wrap the argument, returning a copy -- since otherwise we might
alter a local data structure inadvertantly."""
t = type(value)
if t is types.InstanceType:
matched = false
for dt in daemon_types:
if isinstance(value, dt):
matched = true
if not copy_types and not matched and \
not isinstance(value, DynamicProxy):
return provide_local_object(value)
elif t is types.ListType:
value = value[:]
for i in range(len(value)):
value[i] = wrap(value[i])
elif t is types.TupleType:
value = list(value)
for i in range(len(value)):
value[i] = wrap(value[i])
return tuple(value)
elif t is types.DictType:
copy = {}
for k, v in value.items():
copy[k] = wrap(v)
return copy
return value
def get_remote_object(name, hostname = None, portnum = None):
global client_initialized, pyro_nameserver
# initialize Pyro -- Python Remote Objects
if not client_initialized:
Pyro.core.initClient(verbose)
client_initialized = true
if pyro_nameserver is None or hostname:
pyro_nameserver = find_nameserver(hostname, portnum)
if verbose:
print 'Binding object %s' % name
try:
URI = pyro_nameserver.resolve(name)
if verbose:
print 'URI:', URI
return DynamicProxy(URI)
except Pyro.core.PyroError, x:
raise Error("Couldn't bind object, nameserver says:", x)
class Cache(UserDict.UserDict):
"""simple cache that uses least recently accessed time to trim size"""
def __init__(self,data=None,size=100):
UserDict.UserDict.__init__(self,data)
self.size = size
def resize(self):
"""trim cache to no more than 95% of desired size"""
trim = max(0, int(len(self.data)-0.95*self.size))
if trim:
# don't want self.items() because we must sort list by access time
values = map(None, self.data.values(), self.data.keys())
values.sort()
for val,k in values[0:trim]:
del self.data[k]
def __setitem__(self,key,val):
if (not self.data.has_key(key) and
len(self.data) >= self.size):
self.resize()
self.data[key] = (time.time(), val)
def __getitem__(self,key):
"""like normal __getitem__ but updates time of fetched entry"""
val = self.data[key][1]
self.data[key] = (time.time(),val)
return val
def get(self,key,default=None):
"""like normal __getitem__ but updates time of fetched entry"""
try:
return self[key]
except KeyError:
return default
def values(self):
"""return values, but eliminate access times first"""
vals = list(self.data.values())
for i in range(len(vals)):
vals[i] = vals[i][1]
return tuple(vals)
def items(self):
return map(None, self.keys(), self.values())
def copy(self):
return self.__class__(self.data, self.size)
def update(self, otherdict):
for k in otherdict.keys():
self[k] = otherdict[k]
provided_objects = Cache(size = 100)
def provide_local_object(obj, name = None, hostname = None, portnum = None):
global server_initialized, pyro_daemon, pyro_nameserver
proxy_class = DynamicProxy
if not server_initialized:
Pyro.core.initServer(verbose)
server_initialized = true
if pyro_daemon is None:
pyro_daemon = Pyro.core.Daemon(host = daemon_host,
port = daemon_port)
# If no 'name' was specified, don't even bother with the
# nameserver.
if name:
if pyro_nameserver is None or hostname:
pyro_nameserver = find_nameserver(hostname, portnum)
pyro_daemon.useNameServer(pyro_nameserver)
if verbose:
print 'Remoting object', name
# tell nameserver to forget any earlier use of this name
try:
if pyro_nameserver.resolve(name):
pyro_nameserver.unregister(name)
except Pyro.errors.NamingError:
pass
if not isinstance(obj, Pyro.core.ObjBase):
if provided_objects.has_key(obj):
obj = provided_objects[obj]
else:
slave = ObjBase()
slave.delegateTo(obj)
provided_objects[obj] = slave
obj = slave
URI = pyro_daemon.connect(obj, name)
daemon_objects.append(obj)
proxy = proxy_class(URI)
return proxy
abort = false
def interrupt(*args):
global abort
abort = true
if hasattr(signal,'SIGINT'): signal.signal(signal.SIGINT, interrupt)
#if hasattr(signal,'SIGHUP'): signal.signal(signal.SIGHUP, interrupt)
#if hasattr(signal,'SIGQUIT'): signal.signal(signal.SIGQUIT, interrupt)
def handle_requests(wait_time = None, callback = None):
global abort
abort = false
if pyro_daemon is None:
raise Error("There is no daemon with which to handle requests")
if wait_time:
start = time.time()
while not abort:
try:
pyro_daemon.handleRequests(wait_time)
if wait_time:
now = time.time()
if callback and now - start > wait_time:
callback()
start = now
elif callback:
callback()
# ignore socket and select errors, they are often transient
except socket.error: pass
except Exception, msg:
if verbose:
print "Error:", sys.exc_type, msg
abort = true
except:
abort = true
return abort
def handle_requests_unsafe(wait_time = None, callback = None):
global abort
abort = false
if pyro_daemon is None:
raise Error("There is no daemon with which to handle requests")
if wait_time:
start = time.time()
while 1:
pyro_daemon.handleRequests(wait_time)
if wait_time:
now = time.time()
if callback and now - start > wait_time:
callback()
start = now
elif callback:
callback()
return true
def unregister_object(obj):
if pyro_daemon:
try: pyro_daemon.disconnect(obj)
except: pass
global daemon_objects
if obj in daemon_objects:
daemon_objects.remove(obj)
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