host_test_registry.py

00001 """
00002 mbed SDK
00003 Copyright (c) 2011-2013 ARM Limited
00004 
00005 Licensed under the Apache License, Version 2.0 (the "License");
00006 you may not use this file except in compliance with the License.
00007 You may obtain a copy of the License at
00008 
00009     http://www.apache.org/licenses/LICENSE-2.0
00010 
00011 Unless required by applicable law or agreed to in writing, software
00012 distributed under the License is distributed on an "AS IS" BASIS,
00013 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00014 See the License for the specific language governing permissions and
00015 limitations under the License.
00016 """
00017 
00018 class HostTestRegistry :
00019     """ Simple class used to register and store
00020         host test plugins for further usage
00021     """
00022     # Here we actually store all the plugins
00023     PLUGINS = {}    # 'Plugin Name' : Plugin Object
00024 
00025     def print_error(self, text):
00026         print "Plugin load failed. Reason: %s"% text
00027 
00028     def register_plugin (self, plugin):
00029         """ Registers and stores plugin inside registry for further use.
00030             Method also calls plugin's setup() function to configure plugin if needed.
00031 
00032             Note: Different groups of plugins may demand different extra parameter. Plugins
00033             should be at least for one type of plugin configured with the same parameters
00034             because we do not know which of them will actually use particular parameter.
00035         """
00036         # TODO:
00037         # - check for unique caps for specified type
00038         if plugin.name not in self.PLUGINS :
00039             if plugin.setup(): # Setup plugin can be completed without errors
00040                 self.PLUGINS [plugin.name] = plugin
00041                 return True
00042             else:
00043                 self.print_error ("%s setup failed"% plugin.name)
00044         else:
00045             self.print_error ("%s already loaded"% plugin.name)
00046         return False
00047 
00048     def call_plugin (self, type, capability, *args, **kwargs):
00049         """ Execute plugin functionality respectively to its purpose
00050         """
00051         for plugin_name in self.PLUGINS :
00052             plugin = self.PLUGINS [plugin_name]
00053             if plugin.type == type and capability in plugin.capabilities:
00054                 return plugin.execute(capability, *args, **kwargs)
00055         return False
00056 
00057     def get_plugin_caps (self, type):
00058         """ Returns list of all capabilities for plugin family with the same type.
00059             If there are no capabilities empty list is returned
00060         """
00061         result = []
00062         for plugin_name in self.PLUGINS :
00063             plugin = self.PLUGINS [plugin_name]
00064             if plugin.type == type:
00065                 result.extend(plugin.capabilities)
00066         return sorted(result)
00067 
00068     def load_plugin (self, name):
00069         """ Used to load module from
00070         """
00071         mod = __import__("module_%s"% name)
00072         return mod
00073 
00074     def __str__ (self):
00075         """ User friendly printing method to show hooked plugins
00076         """
00077         from prettytable import PrettyTable
00078         column_names = ['name', 'type', 'capabilities', 'stable']
00079         pt = PrettyTable(column_names)
00080         for column in column_names:
00081             pt.align[column] =  'l'
00082         for plugin_name in sorted(self.PLUGINS .keys()):
00083             name  = self.PLUGINS [plugin_name].name
00084             type  = self.PLUGINS [plugin_name].type
00085             stable = self.PLUGINS [plugin_name].stable
00086             capabilities  = ', '.join(self.PLUGINS [plugin_name].capabilities)
00087             row = [name, type, capabilities, stable]
00088             pt.add_row(row)
00089         return pt.get_string()