Several pieces of code, as well as package.json specify GPL 2.0 as the license, whereas https://github.com/wikimedia/wikidata-query-gui/blob/master/LICENSE is for Apache. According to Apache site, any code under Apache license can be used with GPL software, so that should be no issue.
The license file should say GPL 2.0 or later
I’m not sure if we can just change the LICENSE file – I would think that’s the most obvious place for a contributor to look for the license, so external contributors might have been under the impression that their contribution would be distributed under the terms of the ASL, not the GPL. We should probably ask them to be sure. (git shortlog -se lists about 30 contributors, plus/minus some duplicates because we don’t have a .mailmap yet.)
Do we need WMF-Legal assistance here?
Well, according to Apache's own site we can - because anything submitted under Apache license is usable under GPL. Its like if someone submitted a patch under MIT, and I build a GPL software, i can simply copy paste MIT code without asking for permission. But legal may know better about this topic. BTW, I suspect this file was added when adding Vega Graphs capability about a year ago.
Its like if someone submitted a patch under MIT, and I build a GPL software, i can simply copy paste MIT code without asking for permission.
The MIT license still requires attribution, including the license:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
As far as I understand, you can redistribute the software under the GPL, but you still have to include its original author and license – you’re not allowed to claim that it was always published under the GPL in the first place. Similarly, you can distribute a combination of GPL-licensed code and Apache-licensed code under the GPL, but only if you state which parts were originally published under the Apache license, and by whom.
Hmm I think GUI should be Apache, as it does not rely directly on any GPL code AFAIK. And main docs in WDQS repo says so. I'm not sure why the code has GPL tags, maybe some confusion. My preference is to take it to Apache, but if it's for some reason is impossible, GPL I guess would work too.
@Lydia_Pintscher, would like to hear your opinion - would it be OK if we convert GUI to Apache license as it was intended to be? Or should we convert it to GPL instead?
I don't mind either way. I defer to the people who wrote most of the code.
The people who contributed code should be contacted imho for the reasons Lucas mentioned.