fix: adding a restore API for version control on workflow draft (#33582)

Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

api/services/workflow_restore.py

@@ -0,0 +1,58 @@
+"""Shared helpers for restoring published workflow snapshots into drafts.
+
+Both app workflows and RAG pipeline workflows restore the same workflow fields
+from a published snapshot into a draft. Keeping that field-copy logic in one
+place prevents the two restore paths from drifting when we add or adjust draft
+state in the future. Restore stays within a tenant, so we can safely reuse the
+serialized workflow storage blobs without decrypting and re-encrypting secrets.
+"""
+
+from collections.abc import Callable
+from datetime import datetime
+
+from models import Account
+from models.workflow import Workflow, WorkflowType
+
+UpdatedAtFactory = Callable[[], datetime]
+
+
+def apply_published_workflow_snapshot_to_draft(
+    *,
+    tenant_id: str,
+    app_id: str,
+    source_workflow: Workflow,
+    draft_workflow: Workflow | None,
+    account: Account,
+    updated_at_factory: UpdatedAtFactory,
+) -> tuple[Workflow, bool]:
+    """Copy a published workflow snapshot into a draft workflow record.
+
+    The caller remains responsible for source lookup, validation, flushing, and
+    post-commit side effects. This helper only centralizes the shared draft
+    creation/update semantics used by both restore entry points. Features are
+    copied from the stored JSON payload so restore does not normalize and dirty
+    the published source row before the caller commits.
+    """
+    if not draft_workflow:
+        workflow_type = (
+            source_workflow.type.value if isinstance(source_workflow.type, WorkflowType) else source_workflow.type
+        )
+        draft_workflow = Workflow(
+            tenant_id=tenant_id,
+            app_id=app_id,
+            type=workflow_type,
+            version=Workflow.VERSION_DRAFT,
+            graph=source_workflow.graph,
+            features=source_workflow.serialized_features,
+            created_by=account.id,
+        )
+        draft_workflow.copy_serialized_variable_storage_from(source_workflow)
+        return draft_workflow, True
+
+    draft_workflow.graph = source_workflow.graph
+    draft_workflow.features = source_workflow.serialized_features
+    draft_workflow.updated_by = account.id
+    draft_workflow.updated_at = updated_at_factory()
+    draft_workflow.copy_serialized_variable_storage_from(source_workflow)
+
+    return draft_workflow, False