Using Alembic API from inside application code

Question

I am using SQLite as an application file format (see here for why you would want to do this) for my PySide-based desktop application. That is, when a user uses my app, their

Answer 1

I'm not using Flask so I couldn't make use of the Flask-Alembic library that was already recommended. Instead after quite a bit of tinkering I coded up the following short function to run all of the applicable migrations. I keep all of my alembic-related files under a submodule (folder) called migrations. I actually keep the alembic.ini together with the env.py, which is perhaps a little bit unorthodox. Here's a snippet from my alembic.ini file to adjust for that:

[alembic]
script_location = .

Then I added the following file in the same directory and named it run.py. But wherever you keep your scripts, all you'd need to do is modify the code below to point to the correct paths:

from alembic.command import upgrade
from alembic.config import Config
import os


def run_sql_migrations():
    # retrieves the directory that *this* file is in
    migrations_dir = os.path.dirname(os.path.realpath(__file__))
    # this assumes the alembic.ini is also contained in this same directory
    config_file = os.path.join(migrations_dir, "alembic.ini")

    config = Config(file_=config_file)
    config.set_main_option("script_location", migrations_dir)

    # upgrade the database to the latest revision
    upgrade(config, "head")

Then with that run.py file in place, it allows me to do this in my main code:

from mymodule.migrations.run import run_sql_migrations


run_sql_migrations()