Support KVP access to WMTS, so that clients like TerriaJS will work

[rsignell-usgs]

We love the 100% browser-based TerriaJS client for consuming OGC and ESRI map services (based on Cesium and Leaflet). But currently it won't consume OpenAerialMap imagery because it supports only KVP access to WMTS, not REST.

There is a TerriaJS issue already posted to add REST access to WMTS (TerriaJS/terriajs#2927) , but would it be also possible to support KVP access to WMTS on the OpenAerialMap side to support clients like this?

[mojodna]

Potentially; we really should support it. My 2 hesitations are that KVP requests are a bit more difficult to cache (if only due to the query stream parameters; we have Cloudfront configured to ignore them for a slightly higher hit rate) and the relative difficulty of implementation (though tbh, I haven't looked too deeply into what it entails).

Do you happen to know of a Python implementation that we could lean on?

https://github.com/mapproxy/mapproxy/blob/master/mapproxy/service/wmts.py looks like it could potentially work (or it could sit in front of the OAM tiler to support more protocols, but that feels excessively complex).

[rsignell-usgs]

@mojodna , I'm just a TerriaJS user, not a dev, and I think @kring and the rest of the TerriaJS devs are JS guys, but I looked at
https://github.com/topics/wmts-server
and found this. Could it be useful?
https://github.com/KhaledSharif/SimpleWMTS