Collect db-connections function in single module.

1 files changed, 50 insertions, 0 deletions

diff --git a/gn_auth/auth/db/sqlite3.py b/gn_auth/auth/db/sqlite3.py
new file mode 100644
index 0000000..3d94832
--- /dev/null
+++ b/gn_auth/auth/db/sqlite3.py
@@ -0,0 +1,50 @@
+"""Handle connection to auth database."""
+import sqlite3
+import logging
+import contextlib
+from typing import Any, Callable, Iterator
+
+import traceback
+
+from .protocols import DbCursor, DbConnection
+
+@contextlib.contextmanager
+def connection(db_path: str, row_factory: Callable = sqlite3.Row) -> Iterator[DbConnection]:
+    """Create the connection to the auth database."""
+    logging.debug("SQLite3 DB Path: '%s'.", db_path)
+    conn = sqlite3.connect(db_path)
+    conn.row_factory = row_factory
+    conn.set_trace_callback(logging.debug)
+    conn.execute("PRAGMA foreign_keys = ON")
+    try:
+        yield conn
+    except sqlite3.Error as exc:
+        conn.rollback()
+        logging.debug(traceback.format_exc())
+        raise exc
+    finally:
+        conn.commit()
+        conn.close()
+
+@contextlib.contextmanager
+def cursor(conn: DbConnection) -> Iterator[DbCursor]:
+    """Get a cursor from the given connection to the auth database."""
+    cur = conn.cursor()
+    try:
+        yield cur
+    except sqlite3.Error as exc:
+        conn.rollback()
+        logging.debug(traceback.format_exc())
+        raise exc
+    finally:
+        conn.commit()
+        cur.close()
+
+def with_db_connection(func: Callable[[DbConnection], Any]) -> Any:
+    """
+    Takes a function of one argument `func`, whose one argument is a database
+    connection.
+    """
+    db_uri = current_app.config["AUTH_DB"]
+    with connection(db_uri) as conn:
+        return func(conn)