Add alembic boiler plate for migrations

1 files changed, 86 insertions, 0 deletions

diff --git a/migrations/env.py b/migrations/env.py
new file mode 100644
index 0000000..36ddea1
--- /dev/null
+++ b/migrations/env.py
@@ -0,0 +1,86 @@
+import asyncio
+from logging.config import fileConfig
+
+from alembic import context
+from sqlalchemy import engine_from_config, pool
+from sqlalchemy.ext.asyncio import AsyncEngine
+from sqlalchemy.ext.asyncio.engine import AsyncConnection
+
+# This is a required step by Alembic to properly generate migrations
+import backend.models.orm
+from backend.constants import PSQL_DATABASE_URL
+
+target_metadata = backend.models.orm.base.Base.metadata
+
+# this is the Alembic Config object, which provides
+# access to the values within the .ini file in use.
+config = context.config
+
+# Interpret the config file for Python logging.
+# This line sets up loggers basically.
+fileConfig(config.config_file_name)
+config.set_main_option("sqlalchemy.url", PSQL_DATABASE_URL)
+
+
+def run_migrations_offline() -> None:
+    """
+    Run migrations in 'offline' mode.
+
+    This configures the context with just a URL
+    and not an Engine, though an Engine is acceptable
+    here as well.  By skipping the Engine creation
+    we don't even need a DBAPI to be available.
+
+    Calls to context.execute() here emit the given string to the
+    script output.
+
+    """
+    url = config.get_main_option("sqlalchemy.url")
+    context.configure(
+        url=url,
+        target_metadata=target_metadata,
+        literal_binds=True,
+        dialect_opts={"paramstyle": "named"},
+    )
+
+    with context.begin_transaction():
+        context.run_migrations()
+
+
+def do_run_migrations(connection: AsyncConnection) -> None:
+    """Run all migrations on the given connection."""
+    context.configure(
+        connection=connection,
+        target_metadata=target_metadata,
+        compare_type=True,
+        compare_server_default=True,
+    )
+
+    with context.begin_transaction():
+        context.run_migrations()
+
+
+async def run_migrations_online() -> None:
+    """
+    Run migrations in 'online' mode.
+
+    In this scenario we need to create an Engine
+    and associate a connection with the context.
+    """
+    connectable = AsyncEngine(
+        engine_from_config(
+            config.get_section(config.config_ini_section),
+            prefix="sqlalchemy.",
+            poolclass=pool.NullPool,
+            future=True,
+        ),
+    )
+
+    async with connectable.connect() as connection:
+        await connection.run_sync(do_run_migrations)
+
+
+if context.is_offline_mode():
+    run_migrations_offline()
+else:
+    asyncio.run(run_migrations_online())