refac

Co-Authored-By: Classic298 <27028174+Classic298@users.noreply.github.com>

backend/open_webui/migrations/versions/b8f2c6d91a04_add_postgres_pending_files_index.py

@@ -0,0 +1,39 @@
+"""Add a PostgreSQL index for pending knowledge files."""
+
+import logging
+
+import sqlalchemy as sa
+from alembic import op
+
+revision = 'b8f2c6d91a04'
+down_revision = 'f8c0e5b134cd'
+branch_labels = None
+depends_on = None
+
+INDEX_NAME = 'file_pending_knowledge_idx'
+
+
+def upgrade() -> None:
+    conn = op.get_bind()
+    if conn.dialect.name != 'postgresql':
+        return
+
+    try:
+        with conn.begin_nested():
+            op.create_index(
+                INDEX_NAME,
+                'file',
+                [sa.text("((meta -> 'data') ->> 'knowledge_id')")],
+                postgresql_where=sa.text("(data ->> 'status') IN ('pending', 'processing')"),
+                if_not_exists=True,
+            )
+    except sa.exc.DBAPIError as exc:
+        if exc.connection_invalidated:
+            raise
+        # Alembic records a skipped attempt too; it will not retry on every startup.
+        logging.getLogger(__name__).warning('Skipped PostgreSQL index %s: %s', INDEX_NAME, exc)
+
+
+def downgrade() -> None:
+    if op.get_bind().dialect.name == 'postgresql':
+        op.drop_index(INDEX_NAME, table_name='file', if_exists=True)