# alembic-data

Data Migrations for Alembic/SQLAlchemy.

## State of this Project

This project was originally written as part of Karman but then abandoned in the process of migrating to non-relational databases. No further development will be done.

## Usage

When declaring models you can register specific object instances to be created during migrations. Currently the detection of changes is very rudimentary.

```python
from alembic_data import *

class Model:
  ...

register_object(Model(...))
register_object(Model(...))
```

Alternatively you can declare a model as a *managed model*. A managed model’s instances will be exclusively created by alembic-data. This is probably the most useful application. This way alembic-data can make sure that only objects created via `register_object` will exist in the database.

```python
from alembic_data import *

@managed_model
class Model:
  ...

register_object(Model(...))
register_object(Model(...))
# There will only be 2 instances of Model
```