From da656d958253190be9bc01fa5b84ef2719d0b043 Mon Sep 17 00:00:00 2001
From: ksyasuda <ksyasuda@umich.edu>
Date: Thu, 20 Oct 2022 00:05:58 -0700
Subject: [PATCH] update package

---
 pydb/.gitignore          |  1 +
 pydb/pydb/pydb.py        | 41 ++++++++++++++++++++++------------------
 pydb/tests/test_mysql.py |  2 +-
 3 files changed, 25 insertions(+), 19 deletions(-)

diff --git a/pydb/.gitignore b/pydb/.gitignore
index 7b733dd..ebc86a6 100644
--- a/pydb/.gitignore
+++ b/pydb/.gitignore
@@ -2,6 +2,7 @@
 __pycache__/
 *.py[cod]
 *$py.class
+config.py
 
 # C extensions
 *.so
diff --git a/pydb/pydb/pydb.py b/pydb/pydb/pydb.py
index 0762162..02440ff 100644
--- a/pydb/pydb/pydb.py
+++ b/pydb/pydb/pydb.py
@@ -22,10 +22,13 @@ logger.addHandler(handler)
 
 def convert_query_result(query_res):
     """Return List(elements) from query result List(Tuples(element))."""
-    return [i[0] if len(query_res) == 1 else list(i) for i in query_res]
+    if len(query_res) == 0:
+        logger.warning("Received empty result set from DB")
+        return []
+    return [list(i) for i in query_res] if len(query_res) > 1 else query_res[0][0]
 
 
-class DB_WRAPPER:
+class DbWrapper:
     """Base Class for DB Connection Wrapper"""
 
     def __init__(self, info: DB_INFO, connector, exception=None, dictionary=False):
@@ -44,10 +47,9 @@ class DB_WRAPPER:
             else:
                 self._dictionary = False
                 self._cur = self._conn.cursor()
-            self._Exception = exception if exception is not None else Exception
-        except Exception as exception:
-            logger.critical("Something went wrong connection to DB:", exception)
-            raise exception
+            self._exception = exception if exception is not None else Exception
+        except self._exception as e:
+            raise e
 
     def get_connection(self):
         """Returns the connection object for the DB"""
@@ -67,7 +69,7 @@ class DB_WRAPPER:
         Returns:
             [type]: [description]
         """
-        return self._Exception
+        return self._exception
 
     def query(self, stmt):
         """Queries the db with <stmt>.  Returns list of tuples if there are results."""
@@ -75,7 +77,7 @@ class DB_WRAPPER:
             self._cur.execute(stmt)
             res = self._cur.fetchall()
             return convert_query_result(res) if not self._dictionary else res
-        except self._Exception as exception:
+        except self._exception as exception:
             raise exception
 
     def query_with_commit(self, stmt):
@@ -83,7 +85,7 @@ class DB_WRAPPER:
         try:
             self._cur.execute(stmt)
             self._cur.commit()
-        except self._Exception as exception:
+        except self._exception as exception:
             raise exception
 
     def execute(self, stmt):
@@ -96,7 +98,7 @@ class DB_WRAPPER:
                 if not self._dictionary
                 else self._cur.fetchall()
             )
-        except self._Exception as e:
+        except self._exception as e:
             raise e
 
     def close(self):
@@ -105,12 +107,12 @@ class DB_WRAPPER:
         self._conn.close()
 
 
-class MysqlDB(DB_WRAPPER):
+class MysqlDB(DbWrapper):
     """Mysql Specific Functions"""
 
     def __init__(self, info, dictionary=False):
         """MySQL Connection Wrapper"""
-        DB_WRAPPER.__init__(
+        DbWrapper.__init__(
             self,
             info,
             mysql.connector.connect,
@@ -152,7 +154,8 @@ class MysqlDB(DB_WRAPPER):
     def table_exists(self, schema: str, table: str):
         stmt = f"""
         SELECT COUNT(*) from information_schema.TABLES
-        WHERE TABLE_SCHEMA = '{schema}' and TABLE_NAME = '{table}'
+        WHERE UPPER(TABLE_SCHEMA) = UPPER('{schema}')
+        AND UPPER(TABLE_NAME) = UPPER('{table}')
         """
         return self.query(stmt)[0][0] != 0
 
@@ -196,9 +199,15 @@ class DatabaseManager:
 def db_factory(
     db_info: Union[Dict[str, int], Dict[str, str]], db_type: str, dictionary=False
 ):
+    """Build the correct db wrapper for the db_type."""
     db_type = db_type.strip().lower()
     if db_type == "mysql":
-        return MysqlDB(db_info, dictionary=dictionary)
+        dbo = MysqlDB(db_info, dictionary=dictionary)
+    else:
+        logger.error("ERROR %s not valid", db_type)
+        logger.error("Valid types: [ mysql ]")
+        sys.exit(1)
+    return dbo
     # elif db_type == "snowflake":
     #     return SnowflakeWrapper(
     #         db_info, snowflake.connector.connect, snowflake.connector.Error
@@ -211,7 +220,3 @@ def db_factory(
     #     )
     # elif db_type == 'mariadb':
     #     return _MariaDB(db_info)
-    else:
-        logger.error("ERROR %s not valid", db_type)
-        logger.error("Valid types: [ mysql ]")
-        sys.exit(1)
diff --git a/pydb/tests/test_mysql.py b/pydb/tests/test_mysql.py
index 26a0ea5..f5fa512 100644
--- a/pydb/tests/test_mysql.py
+++ b/pydb/tests/test_mysql.py
@@ -28,4 +28,4 @@ def test_mysql_2():
     db = DatabaseManager(config.MYSQL_INFO, "mysql").__enter__()
     res = db.query("SELECT COUNT(*) FROM dir_map")
     logger.info("Result: %s", res)
-    assert res is not None and res[0] > 0
+    assert res is not None and res > 0