hoàn thành bước tạo docker compose

backend/alembic/env.py

@@ -0,0 +1,58 @@
+"""Alembic environment — wires SQLAlchemy models into the migration engine."""
+
+import os
+from logging.config import fileConfig
+
+from alembic import context
+from sqlalchemy import engine_from_config, pool
+
+# Load app models so Alembic can inspect metadata
+from app.database import Base  # noqa: F401 — registers Base.metadata
+import app.models  # noqa: F401 — registers all ORM classes
+
+# ── Alembic Config object ─────────────────────────────────────────────────────
+config = context.config
+if config.config_file_name is not None:
+    fileConfig(config.config_file_name)
+
+# Inject DATABASE_URL from environment so it is never hard-coded
+database_url = os.environ["DATABASE_URL"]
+config.set_main_option("sqlalchemy.url", database_url)
+
+target_metadata = Base.metadata
+
+
+# ── Offline migrations (no live DB connection) ────────────────────────────────
+def run_migrations_offline() -> None:
+    context.configure(
+        url=database_url,
+        target_metadata=target_metadata,
+        literal_binds=True,
+        dialect_opts={"paramstyle": "named"},
+        compare_type=True,
+    )
+    with context.begin_transaction():
+        context.run_migrations()
+
+
+# ── Online migrations (live DB connection) ────────────────────────────────────
+def run_migrations_online() -> None:
+    connectable = engine_from_config(
+        config.get_section(config.config_ini_section, {}),
+        prefix="sqlalchemy.",
+        poolclass=pool.NullPool,
+    )
+    with connectable.connect() as connection:
+        context.configure(
+            connection=connection,
+            target_metadata=target_metadata,
+            compare_type=True,
+        )
+        with context.begin_transaction():
+            context.run_migrations()
+
+
+if context.is_offline_mode():
+    run_migrations_offline()
+else:
+    run_migrations_online()