TYPO3 Phoenix will use the Aloha Editor to provide its users the smoothest inline editing experience. But contrary to TYPO3, being GPL v3 licensed, Aloha is published under the Affero General Public License Version 3 (AGPL3). What implications does this license have on the development and use of TYPO3?
Let me start with a disclaimer: I'm neither a lawyer, nor am I adept in open source license questions. Therefore this blog post doesn't contain a real answer to the question but is more a collection of what I found while searching for background information.
According to the FSF the AGPL3 is basically like the GPL3 and thus compatible. The basic idea of the GPL license is that you may modify the software and redistribute it, as long as you pass on the source code. Now the blemish with that license is - in the eye of some people at least - that you can modify the source code and provide it as a service to customers without having to publish the code. Because you run it on a server and don't really pass the application to someone else, the GPL doesn't oblige you to make the sources available. The AGPL is supposed to remove that blind spot by requiring to share the source code even when it's run only over a network.
Consequently the AGPL v3 is an extended version of the GPL v3, with the addition of §13 "Remote Network Interaction":
"Notwithstanding any other provision of this License, if you modify the Program, your modified version must prominently offer all users interacting with it remotely through a computer network (if your version supports such interaction) an opportunity to receive the Corresponding Source of your version by providing access to the Corresponding Source from a network server at no charge, through some standard or customary means of facilitating copying of software. This Corresponding Source shall include the Corresponding Source for any work covered by version 3 of the GNU General Public License that is incorporated pursuant to the following paragraph."
To me this sounds more complicated and difficult than it – maybe – is. For the core team of TYPO3 it's no big deal at all: Because we publish all our source code anyway, we automatically adhere to the AGPL. But what about companies providing services on top of TYPO3? Or a TYPO3-based cloud service?
As far as I understand the license, you need to provide the source code of the Aloha Editor to your customers if you modified it. If that is really the case, it only touches that part of TYPO3 and will rarely ever happen. Even if so, it would not be a big deal because: isn't all source code of Aloha available to anyone using it by the simple fact that it's a .js file downloaded by the browser? Isn't that sufficient?
Another question which crossed my mind is if a minified version of Aloha is seen as a "compiled version" or if making it available already satisfies the AGPL requirements. In the end it would be no problem to provide a download link in TYPO3's package manager, if that's really necessary.
Finally I wonder why the great guys from Gentics have chosen the AGPL for Aloha. Their motivation surely has been to foster a community around the project. But, after having read a bit about AGPL, I don't know if it will really help or instead might become a contentious issue among its users.
What do you think, is this a potential issue for TYPO3? Do you have experience with other AGPL-licensed applications?