Didn't found answer yet, but maybe because it is not possible.
OpenLayers has a function ol/source/ImageWMS.getFeatureInfoUrl, used to generate an URL to ask features informations according to coordinates. The function and returned URL work well, but I have an issue with the size limitation of the GET URL.
In my example, I use OpenLayers 5.3 and GeoServer 2.10. If the URL generated has a CQL_FILTER parameter with a very long value like "ID IN (5,9,16,25,89,124,175,234...)" and that the resulted URL is more than 2000 characters, it results in a "URI Too Long" error of course. So I was expecting to try to send the URL in a POST way, but when I try, I get a java.lang.NullPointerException.
So my question is : is it possible to use getFeatureInfoUrl in a POST way to bypass the GET size limitation ?
Many thanks in advance for any answer.
