Copy over files from GN3 repository.

1 files changed, 78 insertions, 0 deletions

diff --git a/gn_auth/auth/db.py b/gn_auth/auth/db.py
new file mode 100644
index 0000000..2ba6619
--- /dev/null
+++ b/gn_auth/auth/db.py
@@ -0,0 +1,78 @@
+"""Handle connection to auth database."""
+import sqlite3
+import logging
+import contextlib
+from typing import Any, Callable, Iterator, Protocol
+
+import traceback
+
+class DbConnection(Protocol):
+    """Type annotation for a generic database connection object."""
+    def cursor(self) -> Any:
+        """A cursor object"""
+        ...
+
+    def commit(self) -> Any:
+        """Commit the transaction."""
+        ...
+
+    def rollback(self) -> Any:
+        """Rollback the transaction."""
+        ...
+
+class DbCursor(Protocol):
+    """Type annotation for a generic database cursor object."""
+    def execute(self, *args, **kwargs) -> Any:
+        """Execute a single query"""
+        ...
+
+    def executemany(self, *args, **kwargs) -> Any:
+        """
+        Execute parameterized SQL statement sql against all parameter sequences
+        or mappings found in the sequence parameters.
+        """
+        ...
+
+    def fetchone(self, *args, **kwargs):
+        """Fetch single result if present, or `None`."""
+        ...
+
+    def fetchmany(self, *args, **kwargs):
+        """Fetch many results if present or `None`."""
+        ...
+
+    def fetchall(self, *args, **kwargs):
+        """Fetch all results if present or `None`."""
+        ...
+
+@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()