[dbexecution] Added missing doc and fixed doc related warning

Also fixed import warnings

beat/backend/python/dbexecution.py

@@ -26,18 +26,25 @@
 ###############################################################################
 
 
-'''Execution utilities'''
+"""
+===========
+dbexecution
+===========
+
+Execution utilities
+"""
 
 import os
 
 import logging
-logger = logging.getLogger(__name__)
 
 import simplejson
 
 # from . import schema
 from .database import Database
-from .message_handler import MessageHandler
+
+
+logger = logging.getLogger(__name__)
 
 
 class DBExecutor(object):
@@ -48,10 +55,11 @@ class DBExecutor(object):
 
       prefix (str): Establishes the prefix of your installation.
 
-      data (dict, str): The piece of data representing the block to be executed.
+      data (dict, str): The piece of data representing the block to be
+        executed.
         It must validate against the schema defined for execution blocks. If a
-        string is passed, it is supposed to be a fully qualified absolute path to
-        a JSON file containing the block execution information.
+        string is passed, it is supposed to be a fully qualified absolute path
+        to a JSON file containing the block execution information.
 
       dataformat_cache (:py:class:`dict`, Optional): A dictionary mapping
         dataformat names to loaded dataformats. This parameter is optional and,
@@ -70,8 +78,8 @@ class DBExecutor(object):
 
     Attributes:
 
-      errors (list): A list containing errors found while loading this execution
-        block.
+      errors (list): A list containing errors found while loading this
+        execution block.
 
       data (dict): The original data for this executor, as loaded by our JSON
         decoder.
@@ -89,15 +97,15 @@ class DBExecutor(object):
       input_list (inputs.InputList): A list of inputs that will be served to
         the algorithm.
 
-      data_sources (list): A list with all data-sources created by our execution
-        loader.
+      data_sources (list): A list with all data-sources created by our
+        execution loader.
 
     """
 
-    def __init__(self, message_handler, prefix, cache_root, data, dataformat_cache=None,
-                 database_cache=None):
+    def __init__(self, message_handler, prefix, cache_root, data,
+                 dataformat_cache=None, database_cache=None):
 
-        # Initialisations
+        # Initialisation
         self.prefix = prefix
         self.databases = {}
         self.views = {}
@@ -112,7 +120,7 @@ class DBExecutor(object):
         self.dataformat_cache = dataformat_cache if dataformat_cache is not None else {}
 
         # Load the data
-        if not isinstance(data, dict): # User has passed a file name
+        if not isinstance(data, dict):  # User has passed a file name
             if not os.path.exists(data):
                 self.errors.append('File not found: %s' % data)
                 return
@@ -134,9 +142,9 @@ class DBExecutor(object):
             # Load the database
             if details['database'] not in self.databases:
 
-                if details['database'] in database_cache: #reuse
+                if details['database'] in database_cache:  # reuse
                     db = database_cache[details['database']]
-                else: #load it
+                else:  # load it
                     db = Database(self.prefix, details['database'],
                                            self.dataformat_cache)
                     database_cache[db.name] = db
@@ -156,7 +164,7 @@ class DBExecutor(object):
             if key not in self.views:
                 view = db.view(details['protocol'], details['set'])
 
-                if details['channel'] == self.data['channel']: #synchronized
+                if details['channel'] == self.data['channel']:  # synchronized
                     start_index, end_index = self.data.get('range', (None, None))
                 else:
                     start_index, end_index = (None, None)
@@ -178,15 +186,16 @@ class DBExecutor(object):
 
         self.message_handler.set_data_sources(self.data_sources)
 
-
     def process(self):
-        self.message_handler.start()
+        """ Starts the message handler"""
 
+        self.message_handler.start()
 
     @property
     def address(self):
-        return self.message_handler.address
+        """ Address of the message handler"""
 
+        return self.message_handler.address
 
     @property
     def valid(self):
@@ -195,6 +204,8 @@ class DBExecutor(object):
 
 
     def wait(self):
+        """Wait for the message handle to finish"""
+
         self.message_handler.join()
         self.message_handler = None