feat: Add kuzu graph db migration (#1146)

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alembic/versions/b9274c27a25a_kuzu_11_migration.py

@@ -0,0 +1,59 @@
+"""kuzu-11-migration
+
+Revision ID: b9274c27a25a
+Revises: e4ebee1091e7
+Create Date: 2025-07-24 17:11:52.174737
+
+"""
+
+import os
+from typing import Sequence, Union
+
+# revision identifiers, used by Alembic.
+revision: str = "b9274c27a25a"
+down_revision: Union[str, None] = "e4ebee1091e7"
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    # This migration is only for multi-user Cognee mode
+    if not os.getenv("ENABLE_BACKEND_ACCESS_CONTROL", "false").lower() == "true":
+        return
+
+    from cognee.base_config import get_base_config
+
+    base_config = get_base_config()
+
+    databases_root = os.path.join(base_config.system_root_directory, "databases")
+    if not os.path.isdir(databases_root):
+        raise FileNotFoundError(f"Directory not found: {databases_root}")
+
+    for current_path, dirnames, _ in os.walk(databases_root):
+        # If file is kuzu graph database
+        if ".pkl" in current_path[-4:]:
+            from cognee.infrastructure.databases.graph.kuzu.kuzu_migrate import (
+                kuzu_migration,
+                read_kuzu_storage_version,
+            )
+            import kuzu
+
+            kuzu_db_version = read_kuzu_storage_version(current_path)
+            if (
+                kuzu_db_version == "0.9.0" or kuzu_db_version == "0.8.2"
+            ) and kuzu_db_version != kuzu.__version__:
+                # Try to migrate kuzu database to latest version
+                kuzu_migration(
+                    new_db=current_path + "new",
+                    old_db=current_path,
+                    new_version=kuzu.__version__,
+                    old_version=kuzu_db_version,
+                    overwrite=True,
+                )
+
+
+def downgrade() -> None:
+    # To downgrade you will have to manually change the backup old kuzu graph databases
+    # stored in the user folder to its previous name and remove the new kuzu graph
+    # database that replaced it
+    pass