add wrapper ducts, including redis

Author: danfrankcb

omniduct/duct.py

@@ -292,7 +292,7 @@ class name if not specified).
 
         atexit.register(self.disconnect)
         self.__prepared = False
-        self.__getting = False
+        self.__preparing = False
         self.__disconnecting = False
         self.__cached_auth = {}
         self.__prepreparation_values = {}
@@ -346,16 +346,16 @@ def for_protocol(cls, key):
     def __getattribute__(self, key):
         try:
             if (not object.__getattribute__(self, '_Duct__prepared')
-                    and not object.__getattribute__(self, '_Duct__getting')
+                    and not object.__getattribute__(self, '_Duct__preparing')
                     and not object.__getattribute__(self, '_Duct__disconnecting')
                     and key in object.__getattribute__(self, '_Duct__prepare_triggers')):
-                object.__setattr__(self, '_Duct__getting', True)
+                object.__setattr__(self, '_Duct__preparing', True)
                 object.__getattribute__(self, 'prepare')()
-                object.__setattr__(self, '_Duct__getting', False)
+                object.__setattr__(self, '_Duct__preparing', False)
         except AttributeError:
             pass
         except Exception as e:
-            object.__setattr__(self, '_Duct__getting', False)
+            object.__setattr__(self, '_Duct__preparing', False)
             raise_with_traceback(e)
         return object.__getattribute__(self, key)
 

omniduct/protocols.py

@@ -13,3 +13,4 @@
 from .remotes.ssh import SSHClient
 from .remotes.ssh_paramiko import ParamikoSSHClient
 from .restful.base import RestClient
+from .wrappers.redis import RedisClient

omniduct/wrappers/__init__.py

@@ -0,0 +1,27 @@
+from abc import abstractmethod
+from omniduct.duct import Duct
+from omniduct.utils.docs import quirk_docs
+
+
+class WrapperClient(Duct):
+
+    DUCT_TYPE = Duct.Type.OTHER
+
+    @quirk_docs('_init', mro=True)
+    def __init__(self, **kwargs):
+        """
+        wrapped (dict): A mapping of default session properties
+        """
+        Duct.__init_with_kwargs__(self, kwargs, port=self.DEFAULT_PORT)
+        self._init(**kwargs)
+
+    @abstractmethod
+    def _init(self):
+        pass
+
+    @property
+    def wrapped_field(self):
+        raise NotImplementedError
+
+    def __getattr__(self, key):
+        return getattr(object.__getattribute__(self, self.wrapped_field), key)

omniduct/wrappers/base.py

@@ -0,0 +1,49 @@
+from __future__ import absolute_import
+
+import redis
+from omniduct.utils.debug import logger
+from .base import WrapperClient
+
+from omniduct.utils.magics import (MagicsProvider, process_line_arguments,
+                                   process_line_cell_arguments)
+
+
+class RedisClient(WrapperClient, MagicsProvider):
+    """
+    This Duct connects to a redis database server using the `redis` python library.
+    """
+    PROTOCOLS = ['redis']
+    DEFAULT_PORT = 6379
+
+    def _init(self):
+        self._redis_connection = None
+
+    def _connect(self):
+        self._redis_connection = redis.Redis(self.host, self.port)
+
+    def _is_connected(self):
+        return hasattr(self, '_redis_connection') and self._redis_connection is not None
+
+    def _disconnect(self):
+        logger.info('Disconnecting from Redis database ...')
+        self.__redis_connection = None
+
+    @property
+    def wrapped_field(self):
+        return '_redis_connection'
+
+    def _register_magics(self, base_name):
+        """
+        The following magic functions will be registered (assuming that
+        the base name is chosen to be 'redis'):
+        - Cell Magics:
+            - `%%redis`: Run the provided command
+
+        Documentation for these magics is provided online.
+        """
+        from IPython.core.magic import register_cell_magic
+
+        @register_cell_magic(base_name)
+        @process_line_cell_arguments
+        def execute_command_magic(*args, **kwargs):
+            return self.execute_command(*args, **kwargs)