Add Alembic to project for database migrations

tofu_api/app.py

@@ -60,12 +60,8 @@ class App(Flask):
         # Import models to fill the metadata object
         import tofu_api.models  # noqa (unused import)
 
-        # Create all tables
-        # TODO: Use migrations instead
-        db.create_all_tables()
 
-
-def create_app() -> Flask:
+def create_app() -> App:
     """
     App factory, returns a Flask app object.
     """

tofu_api/common/database/__init__.py

@@ -1,3 +1 @@
-from .metadata import metadata_obj
-from .model import Model
 from .sqlalchemy import SQLAlchemy

tofu_api/common/database/model.py

@@ -1,10 +0,0 @@
-from sqlalchemy.orm import declarative_base
-
-from .metadata import metadata_obj
-
-__all__ = [
-    'Model',
-]
-
-# Generate declarative base class for database models
-Model = declarative_base(name='Model', metadata=metadata_obj)

tofu_api/common/database/sqlalchemy.py

@@ -1,12 +1,11 @@
 from typing import Optional, cast
 
 from flask import Flask
-from sqlalchemy import MetaData, create_engine
+from sqlalchemy import create_engine
 from sqlalchemy.engine import Engine
 from sqlalchemy.orm import Session, scoped_session, sessionmaker
 
 from tofu_api.common.config import Config
-from .metadata import metadata_obj
 
 __all__ = [
     'SQLAlchemy',
@@ -70,22 +69,3 @@ class SQLAlchemy:
         # For all further purposes, the scoped session should be treated like a regular Session object.
         # Use cast() so we can use Session as the type annotation.
         return cast(Session, self._scoped_session)
-
-    @property
-    def metadata(self) -> MetaData:
-        """
-        Database metadata object.
-        """
-        return metadata_obj
-
-    def create_all_tables(self) -> None:
-        """
-        Create tables in the database for all models defined in the metadata.
-        """
-        self.metadata.create_all(self.engine)
-
-    def drop_all_tables(self) -> None:
-        """
-        Delete tables in the database for all models defined in the metadata.
-        """
-        self.metadata.drop_all(self.engine)

tofu_api/models/__init__.py

@@ -1 +1,5 @@
+# Base model first
+from .base import metadata, BaseModel
+
+# Data models
 from .task import Task

tofu_api/models/base.py

@@ -1,7 +1,9 @@
 from sqlalchemy import MetaData
+from sqlalchemy.orm import declarative_base
 
 __all__ = [
-    'metadata_obj',
+    'metadata',
+    'BaseModel',
 ]
 
 # Define naming convention for constraints
@@ -13,5 +15,8 @@ _naming_convention = {
     "pk": "pk_%(table_name)s"
 }
 
-# Create global metadata object for database schemas
-metadata_obj = MetaData(naming_convention=_naming_convention)
+# Create metadata object for database schemas
+metadata = MetaData(naming_convention=_naming_convention)
+
+# Generate declarative base class for database models
+BaseModel = declarative_base(name='BaseModel', metadata=metadata)

tofu_api/models/task.py

@@ -1,9 +1,9 @@
 from sqlalchemy import Column, Integer, String, Text
 
-from tofu_api.common.database import Model
+from .base import BaseModel
 
 
-class Task(Model):
+class Task(BaseModel):
     """
     Database model for tasks.
     """