On Ubuntu 16.04, the legacy drivers for mongo-cxx-driver are no longer included. FindMongoClient.cmake works for building mongodb_store, but depending packages don't have access to that cmake file, and thus can't find the mongo cxx headers. I'm not a cmake expert, nor do I have particular knowledge about how things should be done here, but exporting the header location in the catkin_package fixed the build for me.
On Ubuntu 16.04, the legacy drivers for mongo-cxx-driver are no longer included. FindMongoClient.cmake works for building mongodb_store, but depending packages don't have access to that cmake file, and thus can't find the mongo cxx headers. I'm not a cmake expert, nor do I have particular knowledge about how things should be done here, but exporting the header location in the catkin_package fixed the build for me.