https://community.cloudera.com/t5/Support-Questions/Apache-Nifi-How-do-I-change-a-value-of-a-window-variable/m-p/239025#M200836 <P>What do you mean by "window variable"? Do you mean a Process Group Variable? If so, you can change it via the UI or REST API (I believe the endpoint is /nifi-api/process-groups/&lt;id&gt;/variable-registry/update-requests). Note that it will stop any affected processors or controller services, then change the variable value, then restart/re-enable the affected components.</P><P>If you mean a Flow File attribute, you can add/change/delete those using the UpdateAttribute processor.</P> Thu, 13 Dec 2018 00:03:43 GMT mburgess 2018-12-13T00:03:43Z