[development] Modules that integrate non-GPL PHP apps violate the GPL.

[Thomas Barregren]

Larry Garfield skrev:
> On Friday 31 August 2007, Thomas Barregren wrote:
>
>   
>> Suppose you have a GPLed program A and another program B. The fact that
>> A depends on B (or vice versa) is not enough to trigger the requirement
>> that B also is GPLed. For an example it is perfect legal to let B be non
>> GPLed if A use fork and exec and similar mechanisms to call B. A special
>> case of this proviso is the "web service loophole". It is only if A uses
>> a function, an object or some other internals of B, or vice versa, that
>> B is required to be GPLed. Thus, for any construction where A and B can
>> collaborate without knowing or assuming anything about each others
>> internals, it is acceptable that B isn't GPLed.
>>
>> So, if you want to build a module that can be used to integrate a
>> software with a license incompatible with GPL, I *believe* that a
>> solution is to build a GPLed Service Provider Interface (SPI) which
>> makes no assumption about the internals of the service providers.
>>
>> Regards,
>> Thomas
>>     
>
> So you are claiming, then, that a Drupal wrapper module for a non-GPLed system 
> that communicated only via REST calls (or similar) but still had no actual 
> function of its own without that non-GPLed system, is legal?
>   

Yes, I think so.

> Just for the record, how many of the people in this thread actually *are* 
> lawyers? :-)

Probably none. I am for sure not a lawyer.

But for what it is worth, I have more than ten years of professional 
experience of reading and writing contracts and licenses. I am not an 
expert. But I have learned a lot, and think of myself as quite well 
versed in these issues. Especially when it comes to Free and Open Source 
Software (FOSS) licensing, which I have taken a great interest in for 
several years.

For those who are interesting to learn more in this interesting field, I 
can recommend following books (available free on-line):

  * http://www.rosenlaw.com/oslbook.htm
  * http://www.oreilly.com/catalog/osfreesoft/book/

Best regards,
Thomas