I am using the QGIS Server 3.4 docker image of CampToCamp from docker hub. I have shapefiles and TIFF files in a /home/gisserver/data/etc/gisserver folder, on a Ubuntu 18.04 machine. In the /home/gisserver/data/etc/gisserver is the project.qgs file with one shapefile layer.
To serve the layer with WMS, I set the following in the project properties, the minimum is checked, under "WMS Capabilties", the "Advertised extent", "CRS restrictions" are checked. In the "CRS restrictions" box, is EPSG:4326, and I used the "Use Current Canvas Extent" button to fill in the values for "Advertised extent".
I started the server in the /home/gisserver/data directory with the command specified on the docker page for QGIS server.
When requesting the capabilities http://localhost:8380/?SERVICE=WMS&REQUEST=GetCapabilities I get the following response
<ServerException>Layer(s) not valid</ServerException>
When removing the layer, and save the project empty, with no layers, I get a proper response. I have checked the layers CRS and the projects CRS is in sync, it is EPSG:4326. I also have set the QGIS_SERVER_LOG_LEVEL to 0, but can't get the logfile.
It looks like it should be located in the /var/log/apache2 directory in the docker container, but all the files in there have 0 byte sizes.
What am I missing?