langflow-ai/langflow · error · Error

Restored version contains no flow data

Error message

Restored version contains no flow data

What it means

Catch-all 500 at the end of the is-installed check: any exception outside the per-client inner try (which degrades gracefully to available:false) is logged ('Error checking MCP configuration') and wrapped. It usually means the failure happened at URL building or the project access step rather than in per-client config inspection.

Source

Thrown at src/frontend/src/hooks/flows/use-restore-version.ts:37

  const restore = useCallback(
    async (
      versionId: string,
      options?: { saveDraft?: boolean; onSuccess?: () => void },
    ) => {
      const saveDraft = options?.saveDraft ?? true;
      setIsRestoring(true);
      try {
        // --- Phase 1: API call + canvas application ---
        // Errors here are shown to the user and abort the restore.
        const response = await api.post(
          `${getURL("FLOWS")}/${flowId}/versions/${versionId}/activate`,
          null,
          { params: { save_draft: saveDraft } },
        );
        const updatedFlow = response.data;

        if (!updatedFlow.data) {
          throw new Error("Restored version contains no flow data");
        }

        queryClient.invalidateQueries({ queryKey: ["useGetFlowVersions"] });
        applyFlowToCanvas(updatedFlow);
        // biome-ignore lint/suspicious/noExplicitAny: legacy
      } catch (err: any) {
        const apiDetail = err?.response?.data?.detail;
        const message = apiDetail ?? err?.message ?? "Unknown error";
        setErrorData({
          title: t("errors.failedToRestoreVersion"),
          list: [message],
        });
        setIsRestoring(false);
        return;
      }

      // --- Phase 2: Post-restore cleanup ---
      // The restore succeeded. Errors here are logged but should not

View on GitHub (pinned to 976ec789d2)

Solutions

1. Read the logged traceback under 'Error checking MCP configuration'.
2. If it is the composer URL error, complete the OAuth settings (host/port) via PATCH and retry.
3. Re-save the project's MCP auth settings so URL builders have all required fields.

auth = project.auth_settings or {}
if auth.get("auth_type") == "oauth" and not (auth.get("oauth_host") and auth.get("oauth_port")):
    print("complete OAuth host/port before checking install status")

except httpx.HTTPStatusError as e:
    if e.response.status_code == 500 and "checking MCP" in e.response.json().get("detail", ""):
        verify_oauth_settings_complete(); retry_after_fix()

When it happens

Trigger: GET the install-check route when get_composer_streamable_http_url/get_composer_sse_url raise (e.g. missing oauth_host/oauth_port — see the composer URL ValueError), or verify_project_access fails with a non-HTTP exception.

Common situations: Project has OAuth auth_type but composer host/port were never populated in auth settings; partially written auth settings after a failed PATCH.

Related errors

• Failed to download flows: ${response.statusText}
• Failed to delete MCP Server
• Failed to patch MCP Server
• Langflow was not able to connect to the server. Please make
• Multiple files are not allowed

AI-assisted analysis of langflow-ai/langflow@976ec789d2 (2026-08-14). Data as JSON: /api/errors/edacee59fd0e9cad. Report an issue: GitHub.