import signal
import socket
+import formencode
import logging ; log = logging.getLogger('pymin.pymindaemon')
from pymin.dispatcher import handler
def test(self, *args):
print 'test:', args
>>> PyminDaemon(Root(), ('', 9999)).run()
+
+ The daemon then will be listening to messages to UDP port 9999. Messages
+ will be dispatcher throgh the pymin.dispatcher mechanism. If all goes ok,
+ an OK response is sent. If there was a problem, an ERROR response is sent.
+
+ The general syntax of responses is::
+
+ (OK|ERROR) LENGTH
+ CSV MESSAGE
+
+ So, first is a response code (OK or ERROR), then it comes the length of
+ the CSV MESSAGE (the bufer needed to receive the rest of the message).
+
+ CSV MESSAGE is the body of the response, which it could be void (if lenght
+ is 0), a simple string (a CVS with only one column and row), a single row
+ or a full "table" (a CSV with multiple rows and columns).
+
+ There are 2 kind of errors considered "normal": dispatcher.Error and
+ formencode.Invalid. In general, response bodies of errors are simple
+ strings, except, for example, for formencode.Invalid errors where an
+ error_dict is provided. In that case the error is a "table", where the
+ first colunm is the name of an invalid argument, and the second is the
+ description of the error for that argument. Any other kind of exception
+ raised by the handlers will return an ERROR response with the description
+ "Internal server error".
+
+ All messages (requests and responses) should be UTF-8 encoded and the CVS
+ responses are formated in "Excel" format, as known by the csv module.
"""
def __init__(self, root, bind_addr=('', 9999), timer=1):
r"handle() -> None :: Handle incoming events using the dispatcher."
(msg, addr) = self.file.recvfrom(65535)
log.debug(u'PyminDaemon.handle: message %r from %r', msg, addr)
+ response = u'ERROR'
try:
result = self.dispatcher.dispatch(unicode(msg, 'utf-8'))
if result is not None:
result = serializer.serialize(result)
- response = u'OK '
+ response = u'OK'
except dispatcher.Error, e:
result = unicode(e) + u'\n'
- response = u'ERROR '
+ except formencode.Invalid, e:
+ if e.error_dict:
+ result = serializer.serialize(e.error_dict)
+ else:
+ result = unicode(e) + u'\n'
except Exception, e:
import traceback
result = u'Internal server error\n'
- response = u'ERROR '
log.exception(u'PyminDaemon.handle: unhandled exception')
if result is None:
- response += u'0\n'
+ response += u' 0\n'
else:
- response += u'%d\n%s' % (len(result), result)
+ response += u' %d\n%s' % (len(result), result)
log.debug(u'PyminDaemon.handle: response %r to %r', response, addr)
self.file.sendto(response.encode('utf-8'), addr)
datefmt = '%H:%M:%S',
)
+ class Scheme(formencode.Schema):
+ mod = formencode.validators.OneOf(['upper', 'lower'], if_empty='lower')
+ ip = formencode.validators.CIDR
+
class Root(dispatcher.Handler):
@handler(u"Print all the arguments, return nothing.")
def test(self, *args):
print 'test:', args
@handler(u"Echo the message passed as argument.")
- def echo(self, message):
+ def echo(self, message, mod=None, ip=None):
+ vals = Scheme.to_python(dict(mod=mod, ip=ip))
+ mod = vals['mod']
+ ip = vals['ip']
+ message = getattr(message, mod)()
print 'echo:', message
return message