Refactored all database backends to inherit from a common base class to remove quite a bit of duplicated code. Thanks for the patch, Brian Harring. Refs #5106

git-svn-id: http://code.djangoproject.com/svn/django/trunk@5949 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/db/backends/__init__.py

@@ -0,0 +1,36 @@
+try:
+    # Only exists in Python 2.4+
+    from threading import local
+except ImportError:
+    # Import copy of _thread_local.py from Python 2.4
+    from django.utils._threading_local import local
+
+class BaseDatabaseWrapper(local):
+    def __init__(self, **kwargs):
+        self.connection = None
+        self.queries = []
+        self.options = kwargs
+
+    def _commit(self):
+        if self.connection is not None:
+            return self.connection.commit()
+
+    def _rollback(self):
+        if self.connection is not None:
+            return self.connection.rollback()
+
+    def close(self):
+        if self.connection is not None:
+            self.connection.close()
+            self.connection = None
+
+    def cursor(self):
+        from django.conf import settings
+        cursor = self._cursor(settings)
+        if settings.DEBUG:
+            return self.make_debug_cursor(cursor)
+        return cursor
+
+    def make_debug_cursor(self, cursor):
+        from django.db.backends import util
+        return util.CursorDebugWrapper(cursor, self)

django/db/backends/ado_mssql/base.py

@@ -4,7 +4,7 @@ ADO MSSQL database backend for Django.
 Requires adodbapi 2.0.1: http://adodbapi.sourceforge.net/
 """
 
-from django.db.backends import util
+from django.db.backends import BaseDatabaseWrapper, util
 try:
     import adodbapi as Database
 except ImportError, e:
@@ -48,46 +48,18 @@ def variantToPython(variant, adType):
     return res
 Database.convertVariantToPython = variantToPython
 
-try:
-    # Only exists in Python 2.4+
-    from threading import local
-except ImportError:
-    # Import copy of _thread_local.py from Python 2.4
-    from django.utils._threading_local import local
-
-class DatabaseWrapper(local):
-    def __init__(self, **kwargs):
-        self.connection = None
-        self.queries = []
-
-    def cursor(self):
-        from django.conf import settings
+class DatabaseWrapper(BaseDatabaseWrapper):
+    def _cursor(self, settings):
         if self.connection is None:
             if settings.DATABASE_NAME == '' or settings.DATABASE_USER == '':
                 from django.core.exceptions import ImproperlyConfigured
-                raise ImproperlyConfigured, "You need to specify both DATABASE_NAME and DATABASE_USER in your Django settings file."
+                raise ImproperlyConfigured("You need to specify both DATABASE_NAME and DATABASE_USER in your Django settings file.")
             if not settings.DATABASE_HOST:
                 settings.DATABASE_HOST = "127.0.0.1"
             # TODO: Handle DATABASE_PORT.
             conn_string = "PROVIDER=SQLOLEDB;DATA SOURCE=%s;UID=%s;PWD=%s;DATABASE=%s" % (settings.DATABASE_HOST, settings.DATABASE_USER, settings.DATABASE_PASSWORD, settings.DATABASE_NAME)
             self.connection = Database.connect(conn_string)
-        cursor = self.connection.cursor()
-        if settings.DEBUG:
-            return util.CursorDebugWrapper(cursor, self)
-        return cursor
-
-    def _commit(self):
-        if self.connection is not None:
-            return self.connection.commit()
-
-    def _rollback(self):
-        if self.connection is not None:
-            return self.connection.rollback()
-
-    def close(self):
-        if self.connection is not None:
-            self.connection.close()
-            self.connection = None
+        return self.connection.cursor()
 
 allows_group_by_ordinal = True
 allows_unique_and_pk = True

django/db/backends/mysql/base.py

@@ -4,7 +4,7 @@ MySQL database backend for Django.
 Requires MySQLdb: http://sourceforge.net/projects/mysql-python
 """
 
-from django.db.backends import util
+from django.db.backends import BaseDatabaseWrapper, util
 try:
     import MySQLdb as Database
 except ImportError, e:
@@ -53,19 +53,10 @@ server_version_re = re.compile(r'(\d{1,2})\.(\d{1,2})\.(\d{1,2})')
 # standard util.CursorDebugWrapper can be used. Also, using sql_mode
 # TRADITIONAL will automatically cause most warnings to be treated as errors.
 
-try:
-    # Only exists in Python 2.4+
-    from threading import local
-except ImportError:
-    # Import copy of _thread_local.py from Python 2.4
-    from django.utils._threading_local import local
-
-class DatabaseWrapper(local):
+class DatabaseWrapper(BaseDatabaseWrapper):
     def __init__(self, **kwargs):
-        self.connection = None
-        self.queries = []
+        super(DatabaseWrapper, self).__init__(**kwargs)
         self.server_version = None
-        self.options = kwargs
 
     def _valid_connection(self):
         if self.connection is not None:
@@ -77,8 +68,7 @@ class DatabaseWrapper(local):
                 self.connection = None
         return False
 
-    def cursor(self):
-        from django.conf import settings
+    def _cursor(self, settings):
         from warnings import filterwarnings
         if not self._valid_connection():
             kwargs = {
@@ -100,29 +90,16 @@ class DatabaseWrapper(local):
                 kwargs['port'] = int(settings.DATABASE_PORT)
             kwargs.update(self.options)
             self.connection = Database.connect(**kwargs)
-            cursor = self.connection.cursor()
-        else:
-            cursor = self.connection.cursor()
+        cursor = self.connection.cursor()
         if settings.DEBUG:
             filterwarnings("error", category=Database.Warning)
-            return util.CursorDebugWrapper(cursor, self)
         return cursor
 
-    def _commit(self):
-        if self.connection is not None:
-            self.connection.commit()
-
     def _rollback(self):
-        if self.connection is not None:
-            try:
-                self.connection.rollback()
-            except Database.NotSupportedError:
-                pass
-
-    def close(self):
-        if self.connection is not None:
-            self.connection.close()
-            self.connection = None
+        try:
+            BaseDatabaseWrapper._rollback(self)
+        except Database.NotSupportedError:
+            pass
 
     def get_server_version(self):
         if not self.server_version:

django/db/backends/mysql_old/base.py

@@ -4,7 +4,7 @@ MySQL database backend for Django.
 Requires MySQLdb: http://sourceforge.net/projects/mysql-python
 """
 
-from django.db.backends import util
+from django.db.backends import BaseDatabaseWrapper, util
 from django.utils.encoding import force_unicode
 try:
     import MySQLdb as Database
@@ -63,19 +63,10 @@ class MysqlDebugWrapper:
         else:
             return getattr(self.cursor, attr)
 
-try:
-    # Only exists in Python 2.4+
-    from threading import local
-except ImportError:
-    # Import copy of _thread_local.py from Python 2.4
-    from django.utils._threading_local import local
-
-class DatabaseWrapper(local):
+class DatabaseWrapper(BaseDatabaseWrapper):
     def __init__(self, **kwargs):
-        self.connection = None
-        self.queries = []
+        super(DatabaseWrapper, self).__init__(**kwargs)
         self.server_version = None
-        self.options = kwargs
 
     def _valid_connection(self):
         if self.connection is not None:
@@ -87,8 +78,7 @@ class DatabaseWrapper(local):
                 self.connection = None
         return False
 
-    def cursor(self):
-        from django.conf import settings
+    def _cursor(self, settings):
         if not self._valid_connection():
             kwargs = {
                 # Note: use_unicode intentonally not set to work around some
@@ -119,25 +109,16 @@ class DatabaseWrapper(local):
                     self.connection.set_character_set('utf8')
         else:
             cursor = self.connection.cursor()
-        if settings.DEBUG:
-            return util.CursorDebugWrapper(MysqlDebugWrapper(cursor), self)
         return cursor
 
-    def _commit(self):
-        if self.connection is not None:
-            self.connection.commit()
+    def make_debug_cursor(self, cursor):
+        return BaseDatabaseWrapper.make_debug_cursor(self, MysqlDebugWrapper(cursor))
 
     def _rollback(self):
-        if self.connection is not None:
-            try:
-                self.connection.rollback()
-            except Database.NotSupportedError:
-                pass
-
-    def close(self):
-        if self.connection is not None:
-            self.connection.close()
-            self.connection = None
+        try:
+            BaseDatabaseWrapper._rollback(self)
+        except Database.NotSupportedError:
+            pass
 
     def get_server_version(self):
         if not self.server_version:

django/db/backends/oracle/base.py

@@ -4,8 +4,7 @@ Oracle database backend for Django.
 Requires cx_Oracle: http://www.python.net/crew/atuining/cx_Oracle/
 """
 
-from django.conf import settings
-from django.db.backends import util
+from django.db.backends import BaseDatabaseWrapper, util
 from django.utils.datastructures import SortedDict
 from django.utils.encoding import smart_str, force_unicode
 import datetime
@@ -19,27 +18,14 @@ except ImportError, e:
     from django.core.exceptions import ImproperlyConfigured
     raise ImproperlyConfigured, "Error loading cx_Oracle module: %s" % e
 
-
 DatabaseError = Database.Error
 IntegrityError = Database.IntegrityError
 
-try:
-    # Only exists in Python 2.4+
-    from threading import local
-except ImportError:
-    # Import copy of _thread_local.py from Python 2.4
-    from django.utils._threading_local import local
-
-class DatabaseWrapper(local):
-    def __init__(self, **kwargs):
-        self.connection = None
-        self.queries = []
-        self.options = kwargs
-
+class DatabaseWrapper(BaseDatabaseWrapper):
     def _valid_connection(self):
         return self.connection is not None
 
-    def cursor(self):
+    def _cursor(self, settings):
         if not self._valid_connection():
             if len(settings.DATABASE_HOST.strip()) == 0:
                 settings.DATABASE_HOST = 'localhost'
@@ -55,23 +41,8 @@ class DatabaseWrapper(local):
         # Set oracle date to ansi date format.
         cursor.execute("ALTER SESSION SET NLS_DATE_FORMAT = 'YYYY-MM-DD'")
         cursor.execute("ALTER SESSION SET NLS_TIMESTAMP_FORMAT = 'YYYY-MM-DD HH24:MI:SS.FF'")
-        if settings.DEBUG:
-            return util.CursorDebugWrapper(cursor, self)
         return cursor
 
-    def _commit(self):
-        if self.connection is not None:
-            return self.connection.commit()
-
-    def _rollback(self):
-        if self.connection is not None:
-            return self.connection.rollback()
-
-    def close(self):
-        if self.connection is not None:
-            self.connection.close()
-            self.connection = None
-
 allows_group_by_ordinal = False
 allows_unique_and_pk = False        # Suppress UNIQUE/PK for Oracle (ORA-02259)
 autoindexes_primary_keys = True

django/db/backends/postgresql/base.py

@@ -5,7 +5,7 @@ Requires psycopg 1: http://initd.org/projects/psycopg1
 """
 
 from django.utils.encoding import smart_str, smart_unicode
-from django.db.backends import util
+from django.db.backends import BaseDatabaseWrapper, util
 try:
     import psycopg as Database
 except ImportError, e:
@@ -15,13 +15,6 @@ except ImportError, e:
 DatabaseError = Database.DatabaseError
 IntegrityError = Database.IntegrityError
 
-try:
-    # Only exists in Python 2.4+
-    from threading import local
-except ImportError:
-    # Import copy of _thread_local.py from Python 2.4
-    from django.utils._threading_local import local
-
 class UnicodeCursorWrapper(object):
     """
     A thin wrapper around psycopg cursors that allows them to accept Unicode
@@ -64,14 +57,8 @@ class UnicodeCursorWrapper(object):
 
 postgres_version = None
 
-class DatabaseWrapper(local):
-    def __init__(self, **kwargs):
-        self.connection = None
-        self.queries = []
-        self.options = kwargs
-
-    def cursor(self):
-        from django.conf import settings
+class DatabaseWrapper(BaseDatabaseWrapper):
+    def _cursor(self, settings):
         set_tz = False
         if self.connection is None:
             set_tz = True
@@ -98,23 +85,8 @@ class DatabaseWrapper(local):
         if not postgres_version:
             cursor.execute("SELECT version()")
             postgres_version = [int(val) for val in cursor.fetchone()[0].split()[1].split('.')]
-        if settings.DEBUG:
-            return util.CursorDebugWrapper(cursor, self)
         return cursor
 
-    def _commit(self):
-        if self.connection is not None:
-            return self.connection.commit()
-
-    def _rollback(self):
-        if self.connection is not None:
-            return self.connection.rollback()
-
-    def close(self):
-        if self.connection is not None:
-            self.connection.close()
-            self.connection = None
-
 allows_group_by_ordinal = True
 allows_unique_and_pk = True
 autoindexes_primary_keys = True

django/db/backends/postgresql_psycopg2/base.py

@@ -4,7 +4,7 @@ PostgreSQL database backend for Django.
 Requires psycopg 2: http://initd.org/projects/psycopg2
 """
 
-from django.db.backends import util
+from django.db.backends import BaseDatabaseWrapper, util
 try:
     import psycopg2 as Database
     import psycopg2.extensions
@@ -15,25 +15,12 @@ except ImportError, e:
 DatabaseError = Database.DatabaseError
 IntegrityError = Database.IntegrityError
 
-try:
-    # Only exists in Python 2.4+
-    from threading import local
-except ImportError:
-    # Import copy of _thread_local.py from Python 2.4
-    from django.utils._threading_local import local
-
 psycopg2.extensions.register_type(psycopg2.extensions.UNICODE)
 
 postgres_version = None
 
-class DatabaseWrapper(local):
-    def __init__(self, **kwargs):
-        self.connection = None
-        self.queries = []
-        self.options = kwargs
-
-    def cursor(self):
-        from django.conf import settings
+class DatabaseWrapper(BaseDatabaseWrapper):
+    def _cursor(self, settings):
         set_tz = False
         if self.connection is None:
             set_tz = True
@@ -60,23 +47,8 @@ class DatabaseWrapper(local):
         if not postgres_version:
             cursor.execute("SELECT version()")
             postgres_version = [int(val) for val in cursor.fetchone()[0].split()[1].split('.')]
-        if settings.DEBUG:
-            return util.CursorDebugWrapper(cursor, self)
         return cursor
 
-    def _commit(self):
-        if self.connection is not None:
-            return self.connection.commit()
-
-    def _rollback(self):
-        if self.connection is not None:
-            return self.connection.rollback()
-
-    def close(self):
-        if self.connection is not None:
-            self.connection.close()
-            self.connection = None
-
 allows_group_by_ordinal = True
 allows_unique_and_pk = True
 autoindexes_primary_keys = True

django/db/backends/sqlite3/base.py

@@ -2,7 +2,7 @@
 SQLite3 backend for django.  Requires pysqlite2 (http://pysqlite.org/).
 """
 
-from django.db.backends import util
+from django.db.backends import BaseDatabaseWrapper, util
 try:
     try:
         from sqlite3 import dbapi2 as Database
@@ -34,21 +34,8 @@ Database.register_converter("TIMESTAMP", util.typecast_timestamp)
 Database.register_converter("decimal", util.typecast_decimal)
 Database.register_adapter(decimal.Decimal, util.rev_typecast_decimal)
 
-try:
-    # Only exists in Python 2.4+
-    from threading import local
-except ImportError:
-    # Import copy of _thread_local.py from Python 2.4
-    from django.utils._threading_local import local
-
-class DatabaseWrapper(local):
-    def __init__(self, **kwargs):
-        self.connection = None
-        self.queries = []
-        self.options = kwargs
-
-    def cursor(self):
-        from django.conf import settings
+class DatabaseWrapper(BaseDatabaseWrapper):
+    def _cursor(self, settings):
         if self.connection is None:
             kwargs = {
                 'database': settings.DATABASE_NAME,
@@ -60,28 +47,15 @@ class DatabaseWrapper(local):
             self.connection.create_function("django_extract", 2, _sqlite_extract)
             self.connection.create_function("django_date_trunc", 2, _sqlite_date_trunc)
             self.connection.create_function("regexp", 2, _sqlite_regexp)
-        cursor = self.connection.cursor(factory=SQLiteCursorWrapper)
-        if settings.DEBUG:
-            return util.CursorDebugWrapper(cursor, self)
-        else:
-            return cursor
-
-    def _commit(self):
-        if self.connection is not None:
-            self.connection.commit()
-
-    def _rollback(self):
-        if self.connection is not None:
-            self.connection.rollback()
+        return self.connection.cursor(factory=SQLiteCursorWrapper)
 
     def close(self):
         from django.conf import settings
         # If database is in memory, closing the connection destroys the
-        # database.  To prevent accidental data loss, ignore close requests on
+        # database. To prevent accidental data loss, ignore close requests on
         # an in-memory db.
-        if self.connection is not None and settings.DATABASE_NAME != ":memory:":
-            self.connection.close()
-            self.connection = None
+        if settings.DATABASE_NAME != ":memory:":
+            BaseDatabaseWrapper.close(self)
 
 class SQLiteCursorWrapper(Database.Cursor):
     """