[Kimchi-devel] [PATCH][Wok 2/5] Creates pluginmanager.py module

[Rodrigo Trujillo]

Signed-off-by: Rodrigo Trujillo <rodrigo.trujillo at linux.vnet.ibm.com>
---
 src/wok/pluginsmanager.py | 133 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 133 insertions(+)
 create mode 100644 src/wok/pluginsmanager.py

diff --git a/src/wok/pluginsmanager.py b/src/wok/pluginsmanager.py
new file mode 100644
index 0000000..b7bb92b
--- /dev/null
+++ b/src/wok/pluginsmanager.py
@@ -0,0 +1,133 @@
+#
+# Project Wok
+#
+# Copyright IBM Corp, 2016
+#
+# Code derived from Project Kimchi
+#
+# This library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 2.1 of the License, or (at your option) any later version.
+#
+# This library 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
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with this library; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301 USA
+#
+
+
+import cherrypy
+import copy
+import os
+from cherrypy.lib.reprconf import Parser
+from configobj import ConfigObj
+
+
+from basemodel import Singleton
+from wok.config import paths, PluginConfig, PluginPaths
+from wok.exception import OperationFailed
+
+
+wok_log = cherrypy.log.error_log
+
+
+class Plugins():
+    __metaclass__ = Singleton
+
+    def __init__(self):
+        # { '<PLUGIN_NAME>': {
+        #     config: <PLUGIN_CONFIG>,
+        #     enabled: <TRUE/FALSE>,
+        #     uri: <PLUGIN_URI_FROM_CONFIG>,
+        #     plugin_class: <PLUGIN_CLASS_FROM_CONFIG>
+        self._plugins_dict = {}
+        self._init_all_plugins()
+
+    def _load_plugin_conf(self, name):
+        plugin_conf = PluginPaths(name).conf_file
+        ret = {}
+        if not os.path.exists(plugin_conf):
+            cherrypy.log.error_log.error("Plugin configuration file %s"
+                                         " doesn't exist." % plugin_conf)
+        else:
+            try:
+                ret = Parser().dict_from_file(plugin_conf)
+            except ValueError as e:
+                msg = "Failed to load plugin conf from %s: %s"
+                cherrypy.log.error_log.error(msg % (plugin_conf, e.message))
+        ret.update(PluginConfig(name))
+        return ret
+
+    def _init_all_plugins(self):
+        plugin_dir = paths.plugins_dir
+        try:
+            dir_contents = os.listdir(plugin_dir)
+        except OSError:
+            return
+        for name in dir_contents:
+            if os.path.isdir(os.path.join(plugin_dir, name)):
+                wok_log.info("Loading plugin: %s" % name)
+                cfg = self._load_plugin_conf(name)
+                plugin_cls = cfg.get('wok', {}).get('plugin_class', '')
+                if plugin_cls == '':
+                    plugin_cls = ('plugins.%s.%s' % (name, name[0].upper() +
+                                                     name[1:]))
+                self._plugins_dict[name] = {
+                    'config': cfg,
+                    'enabled': cfg.get('wok', {}).get('enable', False),
+                    'uri': cfg.get('wok', {}).get('uri', ''),
+                    'plugin_class': plugin_cls,
+                    'conf_file': PluginPaths(name).conf_file
+                }
+
+                if 'wok' in self._plugins_dict[name]['config']:
+                    del self._plugins_dict[name]['config']['wok']
+
+    def get_all_plugins_info(self):
+        return copy.deepcopy(self._plugins_dict)
+
+    def get_plugin_info(self, name):
+        return copy.deepcopy(self._plugins_dict.get(name, {}))
+
+    def get_all_plugins_names(self):
+        ret = self._plugins_dict.keys()
+        ret.sort()
+        return ret
+
+    def get_enabled_plugins(self):
+        ret = [plugin for plugin in self._plugins_dict.keys() if
+               self._plugins_dict[plugin]['enabled']]
+        ret.sort()
+        return ret
+
+    def _enable_plugin_conf_file(self, f_conf, enable=True):
+        try:
+            # 'unrepr' makes ConfigObj read and write characters like ("'?)
+            conf = ConfigObj(infile=f_conf, unrepr=True)
+            conf['wok']['enable'] = enable
+            with open(f_conf, 'wb') as f:
+                conf.write(f)
+        except Exception as e:
+            wok_log.error('Error updating plugin conf file. ' + e.message)
+            raise
+
+    def _change_plugin_state(self, name, enable=True):
+        plugin = self._plugins_dict[name]
+        if plugin['enabled'] == enable:
+            return
+        try:
+            self._enable_plugin_conf_file(plugin['conf_file'], enable)
+        except:
+            raise OperationFailed('WOKPLUG0002E', {'plugin': name})
+        plugin['enabled'] = enable
+
+    def enable_plugin(self, plugin):
+        self._change_plugin_state(plugin, True)
+
+    def disable_plugin(self, plugin):
+        self._change_plugin_state(plugin, False)
-- 
2.1.0