1 files changed, 98 insertions, 0 deletions

diff --git a/scripts/lib/mic/plugin.py b/scripts/lib/mic/plugin.py
new file mode 100644
index 0000000000..18c93ad259
--- /dev/null
+++ b/scripts/lib/mic/plugin.py
@@ -0,0 +1,98 @@
+#!/usr/bin/python -tt
+#
+# Copyright (c) 2011 Intel, 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; version 2 of the License
+#
+# 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, write to the Free Software Foundation, Inc., 59
+# Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+import os, sys
+
+from mic import msger
+from mic import pluginbase
+from mic.conf import configmgr
+from mic.utils import errors
+
+
+__ALL__ = ['PluginMgr', 'pluginmgr']
+
+PLUGIN_TYPES = ["imager", "backend"] # TODO  "hook"
+
+
+class PluginMgr(object):
+    plugin_dirs = {}
+
+    # make the manager class as singleton
+    _instance = None
+    def __new__(cls, *args, **kwargs):
+        if not cls._instance:
+            cls._instance = super(PluginMgr, cls).__new__(cls, *args, **kwargs)
+
+        return cls._instance
+
+    def __init__(self):
+        self.plugin_dir = configmgr.common['plugin_dir']
+
+    def append_dirs(self, dirs):
+        for path in dirs:
+            self._add_plugindir(path)
+
+        # load all the plugins AGAIN
+        self._load_all()
+
+    def _add_plugindir(self, path):
+        path = os.path.abspath(os.path.expanduser(path))
+
+        if not os.path.isdir(path):
+            msger.warning("Plugin dir is not a directory or does not exist: %s"\
+                          % path)
+            return
+
+        if path not in self.plugin_dirs:
+            self.plugin_dirs[path] = False
+            # the value True/False means "loaded"
+
+    def _load_all(self):
+        for (pdir, loaded) in self.plugin_dirs.iteritems():
+            if loaded: continue
+
+            sys.path.insert(0, pdir)
+            for mod in [x[:-3] for x in os.listdir(pdir) if x.endswith(".py")]:
+                if mod and mod != '__init__':
+                    if mod in sys.modules:
+                        #self.plugin_dirs[pdir] = True
+                        msger.warning("Module %s already exists, skip" % mod)
+                    else:
+                        try:
+                            pymod = __import__(mod)
+                            self.plugin_dirs[pdir] = True
+                            msger.debug("Plugin module %s:%s imported"\
+                                        % (mod, pymod.__file__))
+                        except ImportError, err:
+                            msg = 'Failed to load plugin %s/%s: %s' \
+                                % (os.path.basename(pdir), mod, err)
+                            msger.warning(msg)
+
+            del(sys.path[0])
+
+    def get_plugins(self, ptype):
+        """ the return value is dict of name:class pairs """
+
+        if ptype not in PLUGIN_TYPES:
+            raise errors.CreatorError('%s is not valid plugin type' % ptype)
+
+        self._add_plugindir(os.path.join(self.plugin_dir, ptype))
+        self._load_all()
+
+        return pluginbase.get_plugins(ptype)
+
+pluginmgr = PluginMgr()