Sanity checking compatibility approach

[andrew]

I've started this project based on some basic's that I've picked up from https://en.wikipedia.org/wiki/License_compatibility but I'm not that experienced with software licensing laws, would anyone with more experience like advise if this library is barking up the right tree?

[camillem]

Hi, Just a few points regarding /lib/license/compatibility.rb You include 'EPL-1.0' and 'MPL-2.0' in the PERMISSIVE array, while they're generally considered as (weak) copyleft. Regarding copyleft, it's not uncommon to consider two dimensions, the scope (typically permissive/weak/strong copyleft) and the triggering action of obligations (distribution in most licences / network access, like in Affero licences). The licences in your STRONG_COPYLEFT would be more generally qualified as "network copyleft", while "strong copyleft" generally refers to licences like the GPL, CECILL-2.0. You seem to refer to SPDX 1, using licence IDs with "+". Starting with SPDX 2, "+" is considered as an operator in an expression (cf. http://spdx.org/sites/spdx/files/SPDX-2.0.pdf ). I don't know if this is relevant for your approach, but it might (Npm has switched to SPDX 2.0.) HTH

[andrew]

Thanks for the feedback @camillem, I've made a few tweaks based on your suggestions:

• MPL and EPL are now weak copyleft: https://github.com/librariesio/license-compatibility/commit/733ed2c72c1538007856a878c303e908443d3aef
• Rename copyleft to strong copyleft and strong copyleft to network copyleft https://github.com/librariesio/license-compatibility/commit/b1686769df9a0cd4e5660bde54da984bb3d59f7d
• move towards SPDX 2 by ignoring + for now: https://github.com/librariesio/license-compatibility/commit/cc94c79b2532055f65fc06181028cc0777df0415