updated db connection module for ssl confs

igf_data/igfdb/dbconnect.py

@@ -6,31 +6,22 @@ class DBConnect:
   A class for managing dbconnection
   '''
   def __init__(self, **data):
-    data.setdefault('dbhost', '')
-    data.setdefault('dbport', '')
-    data.setdefault('dbuser', '')
-    data.setdefault('dbpass', '')
-    data.setdefault('dbname', '')
-    data.setdefault('url', '')
-    data.setdefault('driver', 'sqlite')
-    data.setdefault('connector', '')
-    data.setdefault('supported_drivers', ('mysql', 'sqlite'))
-    data.setdefault('engine_config', {})
-
-    self.dbhost    = data['dbhost']
-    self.dbport    = data['dbport']
-    self.dbuser    = data['dbuser']
-    self.dbpass    = data['dbpass']
-    self.dbname    = data['dbname']
-    self.driver    = data['driver']
-    self.connector = data['connector']
-    self.supported_drivers = data['supported_drivers']
-    self.engine_config     = data['engine_config']
+    self.dbhost            = data.get('dbhost', '')
+    self.dbport            = data.get('dbport', '')
+    self.dbuser            = data.get('dbuser', '')
+    self.dbpass            = data.get('dbpass', '')
+    self.dbname            = data.get('dbname', '')
+    self.driver            = data.get('driver', 'sqlite')
+    self.connector         = data.get('connector', '')
+    self.supported_drivers = data.get('supported_drivers', ('mysql', 'sqlite'))
+    self.engine_config     = data.get('engine_config', {})
+    self.connect_args      = data.get('connect_args', {})
     # create engine and configure session at start up
-    if data['url'] == '':
+    data_url = data.get('url', '')
+    if data_url == '':
       self.dburl = self._prepare_db_url()                                       # get dburl for connection
     else:
-      self.dburl = data['url']
+      self.dburl = data_url
     self.engine        = self._create_session_engine()                          # get engine connection
     self.session_class = self._configure_session()                              # get session class
 
@@ -48,20 +39,22 @@ def _prepare_db_url(self):
     connector = self.connector
 
     if driver not in self.supported_drivers:
-      raise ValueError('Database driver {0} is not supported yet.'.format(driver)) # check for supported databases
+      raise ValueError(
+        f'Database driver {driver} is not supported yet.') # check for supported databases
 
     if driver != 'sqlite' and (not dbuser or not dbhost):
-      raise ValueError('driver {0} require dbuser and dbhost details, {1},{2}'.format(driver,dbuser,dbhost)) # check for required parameters
+      raise ValueError(
+        f'Driver {driver} require dbuser and dbhost details, {dbuser},{dbhost}') # check for required parameters
 
-    dburl='{0}'.format(driver)
+    dburl = driver
     if connector:  
-      dburl='{0}+{1}'.format(dburl, connector)
-    dburl='{0}://'.format(dburl)
+      dburl = f'{dburl}+{connector}'
+    dburl = f'{dburl}://'
     if dbuser and dbpass and dbhost:
-      dburl='{0}{1}:{2}@{3}'.format(dburl, dbuser, dbpass, dbhost)
+      dburl = f'{dburl}{dbuser}:{dbpass}@{dbhost}'
     if dbport: 
-      dburl='{0}:{1}'.format(dburl, dbport) 
-    dburl='{0}/{1}'.format(dburl, dbname)
+      dburl = f'{dburl}:{dbport}'
+    dburl = f'{dburl}/{dbname}'
     return dburl
 
 
@@ -70,12 +63,16 @@ def _create_session_engine(self):
     An internal method for creating an database engine required for the session 
     '''
     if not hasattr(self, 'dburl'):
-      raise AttributeError('Attribute dburl not defined')
-
+      raise AttributeError(
+        'Attribute dburl not defined')
     try:
-      engine = create_engine(self.dburl, **self.engine_config )    # create engine with additional parameter
+      engine = \
+        create_engine(
+          self.dburl,
+          connect_args=self.connect_args,
+          **self.engine_config )    # create engine with additional parameter
       return engine
-    except:
+    except Exception:
       raise
 
 
@@ -87,9 +84,10 @@ def _configure_session(self):
       raise AttributeError('Attribute engine not defined')
 
     try:
-      session_class=sessionmaker(bind=self.engine)                 # create session class
+      session_class = \
+        sessionmaker(bind=self.engine) # create session class
       return session_class
-    except:
+    except Exception:
       raise
 
 
@@ -100,7 +98,7 @@ def get_session_class(self):
     if not hasattr(self, 'session_class'):
       raise AttributeError('Attribute session_class not defined')
 
-    session_class=self.session_class 
+    session_class = self.session_class 
     return session_class
 
 
@@ -117,7 +115,7 @@ def start_session(self):
     Session=self.session_class
     try:
       self.session=Session()                                       # create session
-    except:
+    except Exception:
       raise 
 
 
@@ -130,7 +128,7 @@ def commit_session(self):
 
     try: 
       self.session.commit()                                        # commit session
-    except:
+    except Exception:
       raise
 
   def rollback_session(self):
@@ -139,7 +137,7 @@ def rollback_session(self):
     '''
     try:
       self.session.rollback()
-    except:
+    except Exception:
       raise
 
   def close_session(self, save_changes=False):
@@ -151,14 +149,14 @@ def close_session(self, save_changes=False):
     if not hasattr(self, 'session'):
       raise AttributeError('Attribute session not defined')
 
-    session=self.session
+    session = self.session
     try:
       if save_changes:
         session.commit()                                             # commit session
       session.close()                                                # close session
       self.session=None                                              # set the session attribute to None
       del self.session                                               # delete session attribute
-    except:
+    except Exception:
       raise
     if hasattr(self, 'session'):
       raise AttributeError('Attribute session not deleted yet')