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

[Aline Manera]

On 05/31/2016 02:51 PM, Rodrigo Trujillo wrote:
> 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 is a new code, right? So not derived from 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>

plugin_class is not part of plugin config anymore.

> +        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', '')

Same I commented above. plugin_class is not used anymore.

> +                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']
> +

Usually the cherrypy configuration for a plugin can not be changed, so 
IMO it should not be part of plugin configuration file.
If plugin code is responsible to loads its configuraiton, we don't need 
to merge the plugin configuration settings with cherrypy configuration 
and the above lines can be removed.

> +    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)