Simple sqlite3 context manager for Python.

withsqlite.py

#!/usr/bin/env python

import sqlite3

class dbopen(object):
    """
    Simple CM for sqlite3 databases. Commits everything at exit.
    """
    def __init__(self, path):
        self.path = path

    def __enter__(self):
        self.conn = sqlite3.connect(self.path)
        self.cursor = self.conn.cursor()
        return self.cursor

    def __exit__(self, exc_class, exc, traceback):
        self.conn.commit()
        self.conn.close()


if __name__ == '__main__':
    with dbopen('./sample.db') as c:
        c.execute("CREATE TABLE seekmap (id text, offset int, length int)")
        c.execute("INSERT INTO seekmap VALUES ('a', 0, 2000)")
        c.execute("INSERT INTO seekmap VALUES ('b', 2000, 3000)")
        c.execute("SELECT * FROM seekmap")
        result = c.fetchall()
        print(result)
        # [(u'a', 0, 2000), (u'b', 2000, 3000)]

I have made a gist with this updated to have type hinting fwarren / withsqlite.py and to pass linting. __init__ needs self.conn and self.cursor but they are not initalized, only type hinted.

self.conn: Connection
self.cursor: Cursor

In actual practice you can typehint execute(), fetchall(), fetchmany() and fetchone() with:

result: Cursor = c.execute()
result: list[Any] = c.fetchall()
result: list[Any] = c.fetchmany()
result: Any = c.fetchone()