OGC endpoints format parameter and HTTP response mime-type not matching

[micpilon]

Geotrellis-Server's HTTP Response Header is always set to respond content in the application/octet-stream format. It would be preferable that the HTTP response mime-type matches the format parameter from the GetMap request.

For instance, .../service=WMS&version=1.3.0&request=GetMap&format=image/png ...
would generate a HTTP request with a Response Header set with a image/png Content-Type.

[Marc-AndreDaviault]

The same thing happens with WCS services

https://datacube.services.geo.ca/ows/elevation?SERVICE=WCS&VERSION=1.1.1&REQUEST=GetCoverage&FORMAT=image/geotiff&IDENTIFIER=hrdsm&BOUNDINGBOX=-1082312.20988501468673348,1355059.31067213672213256,-53842.37186572709470056,2608174.4939643619582057,urn:ogc:def:crs:EPSG::3979&GRIDBASECRS=urn:ogc:def:crs:EPSG::3979&GRIDCS=urn:ogc:def:cs:OGC:0.0:Grid2dSquareCS&GRIDTYPE=urn:ogc:def:method:WCS:1.1:2dSimpleGrid&GRIDORIGIN=-1082312.20988501468673348,2608174.4939643619582057&GRIDOFFSETS=1528.18698071216590506,-1526.32787246312477691

FME error: Exception detected for the GetCoverage operation, returned Content-Type 'application/octet-stream' is not supported.