Added Alembic for migrations

migrations/README

@@ -0,0 +1 @@
+Generic single-database configuration with an async dbapi.

migrations/__init__.py

@@ -0,0 +1 @@
+"""Database migrations system."""

migrations/env.py

@@ -0,0 +1,68 @@
+"""Alembic environment file."""
+
+import asyncio
+from logging.config import fileConfig
+
+from alembic import context
+from sqlalchemy.engine import Connection
+
+from spoolman.database.database import Database, get_connection_url
+from spoolman.database.models import Base
+
+config = context.config
+
+if config.config_file_name is not None:
+    fileConfig(config.config_file_name)
+
+target_metadata = Base.metadata
+
+
+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.
+
+    """
+    context.configure(
+        url=get_connection_url(),
+        target_metadata=target_metadata,
+        literal_binds=True,
+        dialect_opts={"paramstyle": "named"},
+    )
+
+    with context.begin_transaction():
+        context.run_migrations()
+
+
+def do_run_migrations(connection: Connection) -> None:
+    """Run migrations in 'online' mode."""
+    context.configure(connection=connection, target_metadata=target_metadata)
+
+    with context.begin_transaction():
+        context.run_migrations()
+
+
+async def run_async_migrations() -> None:
+    """In this scenario we need to create an Engine and associate a connection with the context."""
+    db = Database(get_connection_url())
+    db.connect()
+
+    if db.engine is None:
+        raise RuntimeError("Engine not created.")
+
+    async with db.engine.connect() as connection:
+        await connection.run_sync(do_run_migrations)
+
+    await db.engine.dispose()
+
+
+if context.is_offline_mode():
+    run_migrations_offline()
+else:
+    asyncio.run(run_async_migrations())

migrations/script.py.mako

@@ -0,0 +1,25 @@
+"""${message}-
+
+Revision ID: ${up_revision}
+Revises: ${down_revision | comma,n}
+Create Date: ${create_date}
+"""
+import sqlalchemy as sa
+from alembic import op
+${imports if imports else ""}
+
+# revision identifiers, used by Alembic.
+revision = ${repr(up_revision)}
+down_revision = ${repr(down_revision)}
+branch_labels = ${repr(branch_labels)}
+depends_on = ${repr(depends_on)}
+
+
+def upgrade() -> None:
+    """Perform the upgrade."""
+    ${upgrades if upgrades else "pass"}
+
+
+def downgrade() -> None:
+    """Perform the downgrade."""
+    ${downgrades if downgrades else "pass"}

migrations/versions/2023_05_27_2146-684d32cf7e4d_initial.py

@@ -0,0 +1,83 @@
+"""initial.
+
+Revision ID: 684d32cf7e4d
+Create Date: 2023-05-27 21:46:24.361353
+"""
+import sqlalchemy as sa
+from alembic import op
+from sqlalchemy.engine.reflection import Inspector
+
+# revision identifiers, used by Alembic.
+revision = "684d32cf7e4d"
+down_revision = None
+branch_labels = None
+depends_on = None
+
+
+def upgrade() -> None:
+    """Perform the upgrade."""
+    conn = op.get_bind()
+    inspector = Inspector.from_engine(conn)  # type: ignore[arg-type]
+    tables = inspector.get_table_names()
+    if "vendor" in tables:
+        # If the vendor table exists, we assume that the initial migration has already been performed.
+        return
+
+    op.create_table(
+        "vendor",
+        sa.Column("id", sa.Integer(), nullable=False),
+        sa.Column("registered", sa.DateTime(), nullable=False, server_default=sa.func.now()),
+        sa.Column("name", sa.String(length=64), nullable=False),
+        sa.Column("comment", sa.String(length=1024), nullable=True),
+        sa.PrimaryKeyConstraint("id"),
+    )
+    op.create_index(op.f("ix_vendor_id"), "vendor", ["id"], unique=False)
+    op.create_table(
+        "filament",
+        sa.Column("id", sa.Integer(), nullable=False),
+        sa.Column("registered", sa.DateTime(), nullable=False, server_default=sa.func.now()),
+        sa.Column("name", sa.String(length=64), nullable=True),
+        sa.Column("vendor_id", sa.Integer(), nullable=True),
+        sa.Column("material", sa.String(length=64), nullable=True),
+        sa.Column("price", sa.Float(), nullable=True),
+        sa.Column("density", sa.Float(), nullable=False),
+        sa.Column("diameter", sa.Float(), nullable=False),
+        sa.Column("weight", sa.Float(), nullable=True, comment="The filament weight of a full spool (net weight)."),
+        sa.Column("spool_weight", sa.Float(), nullable=True, comment="The weight of an empty spool."),
+        sa.Column("article_number", sa.String(length=64), nullable=True),
+        sa.Column("comment", sa.String(length=1024), nullable=True),
+        sa.ForeignKeyConstraint(
+            ["vendor_id"],
+            ["vendor.id"],
+        ),
+        sa.PrimaryKeyConstraint("id"),
+    )
+    op.create_index(op.f("ix_filament_id"), "filament", ["id"], unique=False)
+    op.create_table(
+        "spool",
+        sa.Column("id", sa.Integer(), nullable=False),
+        sa.Column("registered", sa.DateTime(), nullable=False, server_default=sa.func.now()),
+        sa.Column("first_used", sa.DateTime(), nullable=True),
+        sa.Column("last_used", sa.DateTime(), nullable=True),
+        sa.Column("filament_id", sa.Integer(), nullable=False),
+        sa.Column("used_weight", sa.Float(), nullable=False),
+        sa.Column("location", sa.String(length=64), nullable=True),
+        sa.Column("lot_nr", sa.String(length=64), nullable=True),
+        sa.Column("comment", sa.String(length=1024), nullable=True),
+        sa.ForeignKeyConstraint(
+            ["filament_id"],
+            ["filament.id"],
+        ),
+        sa.PrimaryKeyConstraint("id"),
+    )
+    op.create_index(op.f("ix_spool_id"), "spool", ["id"], unique=False)
+
+
+def downgrade() -> None:
+    """Perform the downgrade."""
+    op.drop_index(op.f("ix_spool_id"), table_name="spool")
+    op.drop_table("spool")
+    op.drop_index(op.f("ix_filament_id"), table_name="filament")
+    op.drop_table("filament")
+    op.drop_index(op.f("ix_vendor_id"), table_name="vendor")
+    op.drop_table("vendor")

migrations/versions/__init__.py

@@ -0,0 +1 @@
+"""Database migration versions."""