NetworkObjects | Swift backend / server framework | HTTP library

The problem is that not every Json object in objects has a cluster-member-names field. So when looping through all the objects and trying to access that field (when it does not exist), it throws that KeyError.

To fix this you can use the dict.get('field_name', default_value) function which will allow you to specify a default value if that field does not exist. By default this is usually None.

Example of using dict.get:

Your error definitely points to the linker not finding the correct symbol in the library, as indicated by "error LNK", so headers were correctly found previously.

1. The core library of QGIS is not found
2. The core library is not linked due to a missing dependency LIBS += ... in one of your projects
3. The libraries were compiled with a different compiler than yours, producing an ABI that is not understood by your compiler
4. Your headers and the actual libary differ (for instance if they point to different version QGIS).

You should probably check that the library files you point to are present and corresponds to the right version of QGIS. If linking dynamically, also make sure that all projects depending on it actually include the linker directive LIBS += ....

EDIT: The OP found the problem to be simply the dllexport, that should be dllimport instead for QGIS CORE_EXPORT and GUI_EXPORT variables: