Add configuration and command-line option framework.

[software/pymin.git] / pymin / pymindaemon.py

diff --git a/pymin/pymindaemon.py b/pymin/pymindaemon.py
index 3881857ea29c93d8276e5af33667900a08c1f510..6f4fa736534147539873a93d2be8b5f3dcf3a635 100644 (file)
--- a/pymin/pymindaemon.py
+++ b/pymin/pymindaemon.py
@@ -10,6 +10,8 @@ command-line.
 
 import signal
 import socket
 
 import signal
 import socket

+import formencode
+import logging ; log = logging.getLogger('pymin.pymindaemon')

 
 from pymin.dispatcher import handler
 from pymin import dispatcher
 
 from pymin.dispatcher import handler
 from pymin import dispatcher


@@ -36,6 +38,34 @@ class PyminDaemon(eventloop.EventLoop):
             def test(self, *args):
                 print 'test:', args
     >>> PyminDaemon(Root(), ('', 9999)).run()
             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):
     """
 
     def __init__(self, root, bind_addr=('', 9999), timer=1):


@@ -43,6 +73,7 @@ class PyminDaemon(eventloop.EventLoop):
 
         See PyminDaemon class documentation for more info.
         """
 
         See PyminDaemon class documentation for more info.
         """

+        log.debug(u'PyminDaemon(%r, %r, %r)', root, bind_addr, timer)

         # Timer timeout time
         self.timer = timer
         # Create and bind socket
         # Timer timeout time
         self.timer = timer
         # Create and bind socket


@@ -51,10 +82,12 @@ class PyminDaemon(eventloop.EventLoop):
         sock.bind(bind_addr)
         # Signal handling
         def quit(loop, signum):
         sock.bind(bind_addr)
         # Signal handling
         def quit(loop, signum):

-            print "Shuting down ..."
+            log.debug(u'PyminDaemon quit() handler: signal %r', signum)
+            log.info(u'Shutting down...')

             loop.stop() # tell main event loop to stop
         def reload_config(loop, signum):
             loop.stop() # tell main event loop to stop
         def reload_config(loop, signum):

-            print "Reloading configuration..."
+            log.debug(u'PyminDaemon reload_config() handler: signal %r', signum)
+            log.info(u'Reloading configuration...')

             # TODO iterate handlers list propagating reload action
         def timer(loop, signum):
             loop.handle_timer()
             # TODO iterate handlers list propagating reload action
         def timer(loop, signum):
             loop.handle_timer()


@@ -76,23 +109,29 @@ class PyminDaemon(eventloop.EventLoop):
     def handle(self):
         r"handle() -> None :: Handle incoming events using the dispatcher."
         (msg, addr) = self.file.recvfrom(65535)
     def handle(self):
         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)
         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'
         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'
         except Exception, e:
             import traceback
             result = u'Internal server error\n'

-            traceback.print_exc() # TODO logging!
-            response = u'ERROR '
+            log.exception(u'PyminDaemon.handle: unhandled exception')

         if result is None:
         if result is None:

-            response += u'0\n'
+            response += u' 0\n'

         else:
         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)
 
     def handle_timer(self):
         self.file.sendto(response.encode('utf-8'), addr)
 
     def handle_timer(self):


@@ -101,6 +140,7 @@ class PyminDaemon(eventloop.EventLoop):
 
     def run(self):
         r"run() -> None :: Run the event loop (shortcut to loop())"
 
     def run(self):
         r"run() -> None :: Run the event loop (shortcut to loop())"

+        log.debug(u'PyminDaemon.loop()')

         # Start the timer
         self.handle_timer()
         signal.alarm(self.timer)
         # Start the timer
         self.handle_timer()
         signal.alarm(self.timer)


@@ -108,16 +148,31 @@ class PyminDaemon(eventloop.EventLoop):
         try:
             return self.loop()
         except eventloop.LoopInterruptedError, e:
         try:
             return self.loop()
         except eventloop.LoopInterruptedError, e:

+            log.debug(u'PyminDaemon.loop: interrupted')

             pass
 
 if __name__ == '__main__':
 
             pass
 
 if __name__ == '__main__':
 

+    logging.basicConfig(
+        level   = logging.DEBUG,
+        format  = '%(asctime)s %(levelname)-8s %(message)s',
+        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.")
     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
 
             print 'echo:', message
             return message