db.py

import mysql.connector
import click

from flask import current_app, g
from flask.cli import with_appcontext

def get_db():
    if 'db' not in g:
        g.db = mysql.connector.connect(user='python')
        g.db.cursor().execute("create database if not exists vtrack")
        g.db.commit()
        g.db = mysql.connector.connect(user='python', database='vtrack')

    return g.db

def close_db(e=None):
    db = g.pop('db', None)

    if db is not None:
        db.close()

def init_db():
    db = get_db()
    crs = db.cursor(dictionary=True)
    
    with current_app.open_resource('schema.sql') as f:
        try:
            for _ in crs.execute(f.read(), multi=True):
                pass
        except RuntimeError:
            pass
        db.commit()

@click.command('init-db')
@with_appcontext
def init_db_command():
    # Clear existing data and create new tables
    init_db()
    click.echo('Initialized database')

def init_app(app):
    app.teardown_appcontext(close_db)
    app.cli.add_command(init_db_command)