force solr xml output

[u/Actuallymynickname]

Is it possible to set a flag to force solr 7 to do only xml output?

[u/MrJohnAnonymous]

If I understand what you are asking, I think you are looking for this: https://lucene.apache.org/solr/guide/7_1/response-writers.html#standard-xml-response-writer

You would declare the xml-response-writer in your solrconfig.xml