Fix version output when missing.

[plcapi.git] / PLC / API.py

diff --git a/PLC/API.py b/PLC/API.py
index 5136341..7af3cec 100644 (file)
--- a/PLC/API.py
+++ b/PLC/API.py
@@ -5,7 +5,8 @@
 # Mark Huang <mlhuang@cs.princeton.edu>
 #
 # Copyright (C) 2004-2006 The Trustees of Princeton University
-# $Id: API.py,v 1.7 2006/10/30 16:37:11 mlhuang Exp $
+# $Id$
+# $URL$
 #
 
 import sys
@@ -13,6 +14,18 @@ import traceback
 import string
 
 import xmlrpclib
+import simplejson
+try:
+    # Try to use jsonlib before using simpljson. This is a hack to get around
+    # the fact that the version of simplejson avaialble for f8 is slightly 
+    # faster than xmlrpc but not as fast as jsonlib. There is no jsonlib 
+    # pacakge available for f8, so this has to be installed manually and
+    # is not expected to always be available. Remove this once we move away
+    # from f8 based MyPLC's         
+    import jsonlib
+    json = jsonlib
+except:
+    json = simplejson 
 
 # See "2.2 Characters" in the XML specification:
 #
@@ -83,10 +96,33 @@ except ImportError:
 from PLC.Config import Config
 from PLC.Faults import *
 import PLC.Methods
-from PLC.sendmail import sendmail
+import PLC.Accessors
+
+def import_deep(name):
+    mod = __import__(name)
+    components = name.split('.')
+    for comp in components[1:]:
+        mod = getattr(mod, comp)
+    return mod
 
 class PLCAPI:
-    methods = PLC.Methods.methods
+
+    # flat list of method names
+    native_methods = PLC.Methods.native_methods
+
+    # other_methods_map : dict {methodname: fullpath}
+    # e.g. 'Accessors' -> 'PLC.Accessors.Accessors'
+    other_methods_map={}
+    for subdir in [ 'Accessors' ]:
+        path="PLC."+subdir
+        # scan e.g. PLC.Accessors.__all__
+        pkg = __import__(path).__dict__[subdir]
+        for modulename in getattr(pkg,"__all__"):
+            fullpath=path+"."+modulename
+            for method in getattr(import_deep(fullpath),"methods"):
+                other_methods_map[method] = fullpath
+
+    all_methods = native_methods + other_methods_map.keys()
 
     def __init__(self, config = "/etc/planetlab/plc_config", encoding = "utf-8"):
         self.encoding = encoding
@@ -97,34 +133,44 @@ class PLCAPI:
 
         # Load configuration
         self.config = Config(config)
-       
-       # Initialize mailer
-       self.mailer = sendmail(self.config)
-        
-       # Initialize database connection
+
+        # Initialize database connection
         if self.config.PLC_DB_TYPE == "postgresql":
             from PLC.PostgreSQL import PostgreSQL
             self.db = PostgreSQL(self)
-
         else:
             raise PLCAPIError, "Unsupported database type " + self.config.PLC_DB_TYPE
 
+        # Aspects modify the API by injecting code before, after or
+        # around method calls. -- http://github.com/baris/pyaspects/blob/master/README
+        # 
+        # As of now we only have aspects for OMF integration, that's
+        # why we enable aspects only if PLC_OMF is set to true.
+        if self.config.PLC_OMF_ENABLED:
+            from aspects import apply_omf_aspect
+            apply_omf_aspect()
+
+
     def callable(self, method):
         """
         Return a new instance of the specified method.
         """
 
         # Look up method
-        if method not in self.methods:
+        if method not in self.all_methods:
             raise PLCInvalidAPIMethod, method
 
         # Get new instance of method
         try:
             classname = method.split(".")[-1]
-            module = __import__("PLC.Methods." + method, globals(), locals(), [classname])
+            if method in self.native_methods:
+                fullpath="PLC.Methods." + method
+            else:
+                fullpath=self.other_methods_map[method]
+            module = __import__(fullpath, globals(), locals(), [classname])
             return getattr(module, classname)(self)
         except ImportError, AttributeError:
-            raise PLCInvalidAPIMethod, method
+            raise PLCInvalidAPIMethod, "import error %s for %s" % (AttributeError,fullpath)
 
     def call(self, source, method, *args):
         """
@@ -176,3 +222,17 @@ class PLCAPI:
             data = buildSOAP(kw = {'%sResponse' % method: {'Result': result}}, encoding = self.encoding)
 
         return data
+
+    def handle_json(self, source, data):
+        """
+        Handle a JSON request 
+        """
+        method, args = json.loads(data)
+        try:
+            result = self.call(source, method, *args)
+        except Exception, e:
+            result = str(e)
+       
+        return json.dumps(result) 
+        
+