Unsupported media type error with heroic datasoure

Using heroic datasource with the latest grafana.

Downloaded the heroic plug in for heroic from:

Added the following in the datasource.ts:
this.metricFindQuery = function(query: String) {
// convert query using template.
query = templateSrv.replace(query);

return this.doRequest('/query/metrics', {
  method: 'POST',
  data: query


Here is how I setup the query:

Unsupported media type error error is received.

Tricky for me to help with this question as I am not familiar with Heroic HTTP API.

You can troubleshoot this by inspecting the query Grafana sends to Heroic by using Chrome Dev Tools and compare that to what the query should be according to their HTTP API docs.