Hello everyone!
For several weeks now, we have a recurrent problem when generating some maps from WMS requests, when they contain layers based on a ImageMosaic datastore, serving COG files stored on an object storage.
The images are used as basemap with other data on top of them. We have a mosaic for each zoom level of the basemap and they are all stacked in a layer group.
The maps are used to generate a PDF document on a given area. When the error occurs, all the maps for the give area don’t contain the data of the basemap. From the service point of view, there is no error (http 200 code is returned) so we have to rely on image analysis to detect the maps with error.
When the error occurs, I can find in the GeoServer logs a message like the following:
[lite.gridcoverage2d] - Unable to renderer this raster, no workaround found
followed by a Java exception, with 3 different flavors:
- The most frequent one is [lite.gridcoverage2d] - Unable to renderer this raster, no workaround found
- java.lang.NullPointerException: Cannot load from byte/boolean array because “string” is null
- java.lang.NullPointerException: Cannot read the array length because “oldString” is null
The last two exceptions are related with the GeoSolutions library imageio-ext.
We tried different versions of geoserver (2.28, 2.27 and 2.26) but we have the same behavior on all of them.
If you have any idea on the cause of these errors or how to get more information on the error itself?
Is it possible to have a real error on the web service call?
Regards
Alexandre