While SPARQL endpoint for Blazegraph and WDQS supports only GET requests, many SPARQL query tools (e.g. http://openuplabs.tso.co.uk/demos/sparqleditor) insist on only sending POST requests. We may want to consider converting POST to GET in nginx or varnish if possible, in order to serve such tools, or use redirect.
See also: https://en.wikipedia.org/wiki/Post/Redirect/Get
https://en.wikipedia.org/wiki/HTTP_303