Use context manager for all db connections

src/scry/__init__.py

@@ -3,15 +3,14 @@
     "get_random_card",
     "get_card_list",
     "insert_cards",
-    "db_connect",
     "db_stats",
     "get_total_cards",
     "clear_database",
     "set_codes",
     "transform_card",
 ]
 
-from .db_setup import create_table, db_connect, clear_database
+from .db_setup import create_table, clear_database
 from .db_insert import insert_cards, transform_card
 from .request import get_random_card, get_card_list, set_codes
 from .db_queries import db_stats, get_total_cards

src/scry/cli.py

@@ -209,7 +209,7 @@ def handle_stats(args, db_connection):
 def handle_clear(args, db_connection):
     # HACK: why does this only work with db_connection and args, even though neither
     # are required? Same with handle_setlist...
-    clear_database()
+    clear_database(db_connection)
 
 
 # Helper functions:

src/scry/db_setup.py

@@ -1,15 +1,4 @@
 # create SQLITE database and tables, insert into table
-import sqlite3
-from pathlib import Path
-from os import makedirs
-
-# set path (if required) for db: scry/data/cards.db
-path_to_root = Path(__file__).parent.parent.parent  # project root scry/
-makedirs(path_to_root / "data/", exist_ok=True)
-
-
-def db_connect():
-    return sqlite3.connect(Path(path_to_root / "data" / "cards.db"))
 
 
 def create_table(connection):
@@ -35,17 +24,19 @@ def create_table(connection):
     connection.commit()
 
 
-def clear_database() -> None:
+def drop_table(connection) -> None:
+    try:
+        cursor = connection.cursor()
+        cursor.execute("DROP TABLE IF EXISTS cards;")
+
+    except Exception as err:
+        print(f"Error clearing database: {err}")
+
+
+def clear_database(connection) -> None:
     check = input("This will delete your database, are you sure? (y/N): ")
     if check.lower() == "y":
-        try:
-            connection = db_connect()
-            cursor = connection.cursor()
-            cursor.execute("DROP TABLE IF EXISTS cards")
-            cursor.close()
-            print("Database exiled to graveyard and removed from game...")
-
-        except Exception as err:
-            print(f"Error clearing database: {err}")
+        drop_table(connection)
+        print("Your database has been exiled to the graveyard and removed from game...")
     else:
         print("Damnation avoided.")

src/scry/main.py

@@ -2,30 +2,36 @@
 # by thrly
 
 
-from . import (
-    create_table,
-    db_connect,
-)
-from .cli import (
-    build_arg_parser,
-)
+from .db_setup import create_table
+from .cli import build_arg_parser
+
+from contextlib import closing
+import sqlite3
+from pathlib import Path
+from os import makedirs
+
+# set path (if required) for db: scry/data/cards.db
+path_to_root = Path(__file__).parent.parent.parent  # project root scry/
+makedirs(path_to_root / "data/", exist_ok=True)
 
 
 def main(argv=None):
-    connection = db_connect()
 
     # setup argument parsing (argv for testing)
     parser = build_arg_parser()
     args = parser.parse_args(argv)
 
-    try:
-        # setup / connect to local database
-        create_table(connection)
+    # use auto-closing context manager to create db connection, pass it to handlers
+    with closing(
+        sqlite3.connect(Path(path_to_root / "data" / "cards.db"))
+    ) as connection:
+
+        try:
+            # setup / connect to local database
+            create_table(connection)
 
-        # execute commands from cli arguments (see cli.py for handling)
-        args.func(args, connection)
+            # execute commands from cli arguments (see cli.py for handling)
+            args.func(args, connection)
 
-    except Exception as err:
-        print("Error in main(): ", err)
-    finally:
-        connection.close()  # finally close db connection
+        except Exception as err:
+            print("Error in main(): ", err)

tests/test_db.py

@@ -4,12 +4,13 @@
 from src.scry.db_insert import insert_cards
 from tests.sample_card import sample_card
 from pathlib import Path
+from contextlib import closing
 
 
 def test_card_insert_and_get():
     path_test_db = Path(__file__).parent
-    connection = sqlite3.connect(Path(path_test_db) / "tests.db")
-    try:
+    with closing(sqlite3.connect(Path(path_test_db) / "tests.db")) as connection:
+
         create_table(connection)
 
         assert insert_cards([sample_card()], datetime.datetime.now(), connection) == 1
@@ -30,5 +31,5 @@ def test_card_insert_and_get():
         assert card[7] == "{G}"  # mana_cost
         assert card[8] == 1.0  # cmc
 
-    finally:
-        connection.close()
+        cursor.execute("DROP TABLE cards;")
+        # TODO: look into pytest's fixtures for automatic teardown/cleanup