feat: add SQLite migration runner

src/fastapi_oidc_op/store/sqlite/migrations.py

@@ -0,0 +1,48 @@
+from pathlib import Path
+
+import aiosqlite
+
+
+async def run_migrations(db: aiosqlite.Connection, migrations_dir: Path) -> int:
+    """Apply unapplied SQL migration files in order. Returns count of newly applied migrations."""
+    if not migrations_dir.is_dir():
+        raise FileNotFoundError(f"Migrations directory not found: {migrations_dir}")
+
+    await db.execute(
+        """
+        CREATE TABLE IF NOT EXISTS _migrations (
+            id INTEGER PRIMARY KEY,
+            filename TEXT NOT NULL UNIQUE,
+            applied_at TEXT NOT NULL DEFAULT (datetime('now'))
+        )
+        """
+    )
+    await db.commit()
+
+    async with db.execute("SELECT filename FROM _migrations") as cursor:
+        applied = {row[0] async for row in cursor}
+
+    migration_files = sorted(migrations_dir.glob("*.sql"))
+
+    count = 0
+    for migration_file in migration_files:
+        if migration_file.name in applied:
+            continue
+        sql = migration_file.read_text(encoding="utf-8")
+        await db.execute("BEGIN")
+        try:
+            for statement in sql.split(";"):
+                statement = statement.strip()
+                if statement:
+                    await db.execute(statement)
+            await db.execute(
+                "INSERT INTO _migrations (filename) VALUES (?)",
+                (migration_file.name,),
+            )
+            await db.commit()
+        except Exception:
+            await db.rollback()
+            raise
+        count += 1
+
+    return count

tests/test_store/test_migrations.py

@@ -0,0 +1,42 @@
+from pathlib import Path
+
+import aiosqlite
+
+from fastapi_oidc_op.store.sqlite.migrations import run_migrations
+
+MIGRATIONS_DIR = (
+    Path(__file__).resolve().parent.parent.parent / "src" / "fastapi_oidc_op" / "store" / "sqlite" / "migrations"
+)
+
+
+async def test_run_migrations_applies_initial() -> None:
+    async with aiosqlite.connect(":memory:") as db:
+        await db.execute("PRAGMA foreign_keys=ON")
+        count = await run_migrations(db, MIGRATIONS_DIR)
+        assert count == 1
+        async with db.execute("SELECT name FROM sqlite_master WHERE type='table' AND name='users'") as cursor:
+            row = await cursor.fetchone()
+        assert row is not None
+
+
+async def test_run_migrations_skips_already_applied() -> None:
+    async with aiosqlite.connect(":memory:") as db:
+        await db.execute("PRAGMA foreign_keys=ON")
+        first_count = await run_migrations(db, MIGRATIONS_DIR)
+        second_count = await run_migrations(db, MIGRATIONS_DIR)
+        assert first_count == 1
+        assert second_count == 0
+
+
+async def test_run_migrations_creates_all_tables() -> None:
+    async with aiosqlite.connect(":memory:") as db:
+        await db.execute("PRAGMA foreign_keys=ON")
+        await run_migrations(db, MIGRATIONS_DIR)
+        async with db.execute("SELECT name FROM sqlite_master WHERE type='table' ORDER BY name") as cursor:
+            tables = [row[0] async for row in cursor]
+        assert "users" in tables
+        assert "user_groups" in tables
+        assert "webauthn_credentials" in tables
+        assert "password_credentials" in tables
+        assert "magic_links" in tables
+        assert "_migrations" in tables