Say a part of the JavaScript which is provided to the client's browser is under GPL. Does this mean that server-side code also has to be made public under GPL as well?
The GPL states:
"You must cause any work that you distribute or publish, that in whole or in part contains or is derived from the Program or any part thereof, to be licensed as a whole at no charge to all third parties under the terms of this License."
It seems to me that since the whole web app will not be complete without the client-side code, it can be considered to "contain" the client-side code, and thus the server-side code is also a part of the whole "work" defined here.