Base server complete including modules, STOMP protocol over Websockets

and ZMQ Router/Dealer implementations.

gns3server/module_manager.py

@@ -0,0 +1,114 @@
+# -*- coding: utf-8 -*-
+#
+# Copyright (C) 2013 GNS3 Technologies Inc.
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import imp
+import inspect
+import pkgutil
+from .modules import IModule
+
+import logging
+log = logging.getLogger(__name__)
+
+
+class Module(object):
+    """
+    Module representation for the module manager
+
+    :param name: module name
+    :param cls: module class to be instantiated when
+    the module is activated
+    """
+
+    def __init__(self, name, cls):
+
+        self._name = name
+        self._cls = cls
+
+    @property
+    def name(self):
+
+        return self._name
+
+    @name.setter
+    def name(self, new_name):
+        self._name = new_name
+
+    #@property
+    def cls(self):
+        return self._cls
+
+
+class ModuleManager(object):
+    """
+    Manages modules
+
+    :param module_paths: path from where module are loaded
+    """
+
+    def __init__(self, module_paths=['modules']):
+
+        self._modules = []
+        self._module_paths = module_paths
+
+    def load_modules(self):
+        """
+        Finds all the possible modules (classes with IModule as a parent)
+        """
+
+        for _, name, ispkg in pkgutil.iter_modules(self._module_paths):
+            if (ispkg):
+                log.debug("analyzing {} package directory".format(name))
+                try:
+                    file, pathname, description = imp.find_module(name, self._module_paths)
+                    module = imp.load_module(name, file, pathname, description)
+                    classes = inspect.getmembers(module, inspect.isclass)
+                    for module_class in classes:
+                        if issubclass(module_class[1], IModule):
+                            # make sure the module class has IModule as a parent
+                            if module_class[1].__module__ == name:
+                                log.info("found and loading {} module".format(module_class[0].lower()))
+                                info = Module(name=module_class[0].lower(), cls=module_class[1])
+                                self._modules.append(info)
+                except:
+                    log.warning("error while analyzing {} package directory".format(name))
+                finally:
+                    if file:
+                        file.close()
+
+    def get_all_modules(self):
+        """
+        Returns all modules.
+
+        :return: list of Module objects
+        """
+
+        return self._modules
+
+    def activate_module(self, module, args=(), kwargs={}):
+        """
+        Activates a given module.
+
+        :param module: module to activate (Module object)
+        :param args: args passed to the module
+        :param kwargs: kwargs passed to the module
+        :return: instantiated module class
+        """
+
+        module_class = module.cls()
+        module_instance = module_class(name=module.name, args=args, kwargs={})
+        log.info("activating {} module".format(module.name))
+        return module_instance