Merge branch 'issue-6' into 'master'

properly check command arguments #6

agent.py

@@ -15,10 +15,12 @@ import tarfile
 from os.path import expanduser, join, exists
 from os.path import expanduser, join, exists
 from os import mkdir, environ
 from os import mkdir, environ
 from glob import glob
 from glob import glob
+from inspect import getargspec
 from StringIO import StringIO
 from StringIO import StringIO
 from base64 import decodestring
 from base64 import decodestring
 from shutil import rmtree, move
 from shutil import rmtree, move
 from datetime import datetime
 from datetime import datetime
+from types import FunctionType
 
 
 from utils import SerialLineReceiverBase
 from utils import SerialLineReceiverBase
 
 
@@ -346,21 +348,41 @@ class SerialLineReceiver(SerialLineReceiverBase):
         self.send_response(response='status',
         self.send_response(response='status',
                            args=args)
                            args=args)
 
 
-    def handle_command(self, command, args):
+    def _get_command(self, command, args):
         if not isinstance(command, basestring) or command.startswith('_'):
         if not isinstance(command, basestring) or command.startswith('_'):
-            raise Exception(u'Invalid command: %s' % command)
-
-        for k, v in args.iteritems():
-            if not (isinstance(v, int) or isinstance(v, float) or
-                    isinstance(v, basestring)):
-                raise Exception(u'Invalid argument: %s' % k)
-
+            raise AttributeError(u'Invalid command: %s' % command)
         try:
         try:
             func = getattr(Context, command)
             func = getattr(Context, command)
-            retval = func(**args)
-        except (AttributeError, TypeError) as e:
-            raise Exception(u'Command not found: %s (%s)' % (command, e))
+        except AttributeError as e:
+            raise AttributeError(u'Command not found: %s (%s)' % (command, e))
+
+        if not isinstance(func, FunctionType):
+            raise AttributeError("Command refers to non-static method %s." %
+                                 unicode(func))
+
+        # check for unexpected keyword arguments
+        argspec = getargspec(func)
+        if argspec.keywords is None:  # _operation doesn't take ** args
+            unexpected_kwargs = set(args) - set(argspec.args)
+            if unexpected_kwargs:
+                raise TypeError(
+                    "Command %s got unexpected keyword arguments: %s" % (
+                        unicode(func), ", ".join(unexpected_kwargs)))
+
+            if argspec.defaults:
+                mandatory_args = argspec.args[0:-len(argspec.defaults)]
             else:
             else:
+                mandatory_args = argspec.args
+            missing_kwargs = set(mandatory_args) - set(args)
+            if missing_kwargs:
+                raise TypeError("Command %s missing arguments: %s" % (
+                    unicode(func), ", ".join(missing_kwargs)))
+
+        return func
+
+    def handle_command(self, command, args):
+        func = self._get_command(command, args)
+        retval = func(**args)
         self.send_response(
         self.send_response(
             response=func.__name__,
             response=func.__name__,
             args={'retval': retval, 'uuid': args.get('uuid', None)})
             args={'retval': retval, 'uuid': args.get('uuid', None)})