WCS failure in QGIS

Hi there,

Anyone seen and fixed this issue trying to open a WCS service provided by a configuration in Sentinel hub in QGIS?

2021-10-06T21:25:52 CRITICAL Invalid Layer : WCS provider Cannot get test dataset.

        Raster layer Provider is not valid (provider: wcs, URI: 


Hi @alex.clark ,

there seems to be a problem with how you filter dates in your evalscript. The indexOf method seems to systematically return -1. I have created a layer in your configuration with a method that works (could be more elegant).

The current layer added to your configuration works fine with WMS in QGIS but also WCS (only outside of QGIS). We are currently investigating why QGIS won’t display this WCS layer and will get back to you when we have some answers.

Hi @alex.clark ,

It seems like QGIS does a test request at a random location in WGS84 (BBOX=-29.99999003287933164,-14.99999501643966582,29.99999003287933164,14.99999501643966582&CRS=EPSG:3857) but uses the CRS specified by us as a user. This part is implemented in QGIS and we cannot do anything about this.

Since there is no data available for that test location on the specified dates, the WCS request fails. What we can do is that we account for this case and add one of the following conditions to the evalscripts:

function evaluatePixel(samples,scenes) {  
  if (scenes.length == 0) return [0];
  //if (scenes.length != 2) return [0];

Since you are comparing data from before and after a fire event, and only allow two possible dates in your evalscripts anyways, you can also use the second if statement instead of the first one.

A configuration with the adjusted evalscripts has been copied to your account (configuration name: [NEW] Nyaliga_2021)

If you connect to the configuration’s WCS endpoint in QGIS, you should be able to add the 1-Band layer to your project. You just have to adjust the value stretching to 0-255 as shown in the screenshot below.

The DMBR_Current layer should visualise without any problems now.