LWN: Comments on "RethinkDB source relicensed, donated to the Linux Foundation"

Affero not harmful

micka — Tue, 14 Feb 2017 10:57:32 +0000

If it's RocksDB, then I think it's a fork of LevelDB.
(I just recently had a dive into these kind of databases)
Those are key-values DB AFAIK (while mongodb is a document database).

Affero not harmful

Cyberax — Mon, 13 Feb 2017 08:28:25 +0000

No, it's not. Any code that is dual-licensed under a proprietary license is not free. It's merely shareware.

And I can't even find what RockDB is...

Fun fact, Mongo's license disclaimer actually can NOT be legally applied by their downstream forks.

Affero not harmful

ncm — Mon, 13 Feb 2017 07:56:24 +0000

Getting code into Mongo's github would take a copyright assignment, as with FSF. (And you would need to persuade them to pull it, likely not an easy task.) But, just as with FSF, you are free to fork the source and distribute it with your own code. People do, e.g. RockDB. So, Free. If they change the license, you still have your code and your fork.

Enterprise customers do get a different license that gives them access to extra stuff they want. But none of that is necessary to use or to change and redistribute the code. As you note, Mongo specifically disclaim ownership of your "views" etc. So, what is not Free? That you can't take it proprietary, as you can with PosgreSQL? How are they different, in that way, from Red Hat?

Affero not harmful

Cyberax — Fri, 10 Feb 2017 18:15:22 +0000

> Are they free? (I don't have a clue.) Or does the copyright assignment have clauses (like the FSF do) preventing the closure of the code?
MongoDB's CLA gives Mongo unconditional rights to do anything they want with contributions.

Affero not harmful

Wol — Fri, 10 Feb 2017 15:40:51 +0000

> This is clearly insane. So MongoDB has a public interpretation of the license that excludes normal database users from AGPL's reach. But they are free to rescind this interpretation at any moment - it won't be retroactive but any code running within future MongoDB versions won't be protected from AGPL.

Are they free? (I don't have a clue.) Or does the copyright assignment have clauses (like the FSF do) preventing the closure of the code?

The FSF can't close any code they've been given the copyright to, because part of the copyright transfer forbids it.

Cheers,
Wol

Affero not harmful

Cyberax — Thu, 09 Feb 2017 05:50:16 +0000

Ok, let me quickly recap what several lawyers told me.

First, enterprise MongoDB has a special commercial license for the DATABASE itself. Not just for additional tools. Consequently, contributing to MongoDB requires copyright assignment to Mongo ( https://www.mongodb.com/legal/contributor-agreement ).

Next, let's talk about AGPL. It poorly defines what "derived works" actually are, just as regular GPL licenses. However, there are some guidelines (including from the FSF itself). In particular, if a program uses internal structures of another system, is tightly bound to it and works in the same address space then it's pretty certain that it's a derived work and GPL applies.

In case of MongoDB most real databases will have views, map/reduce queries and other code that fit these conditions perfectly. So their code can be considered a derived work of Mongo and will have to be disclosed as per AGPL if its output is used (for example) to render HTML pages.

This is clearly insane. So MongoDB has a public interpretation of the license that excludes normal database users from AGPL's reach. But they are free to rescind this interpretation at any moment - it won't be retroactive but any code running within future MongoDB versions won't be protected from AGPL.

And before people start telling that "but Mongo queries are just like C code being processed by GCC" - they are not. They are more comparable with GCC plugins and FSF's opinion is that they must be GPL.

Affero not harmful

ncm — Thu, 09 Feb 2017 01:01:54 +0000

Cy, when did you start peddling falsehoods on LWN?

Large companies who buy support get management tools and help. The database itself really is free, and Free, in every sense, but it's the nature of databases used for Important Things to need competent management, which never comes cheap.

Everything the management tools do could be done by hand, or with custom scripts, but it doesn't take long for a large company to discover that that is the more expensive course.

Resolutely getting back on topic, the Affero license and a really-truly free database substrate has demonstratedly done MongoDB no harm. Look elsewhere for explanations.

Affero not harmful

Wol — Wed, 08 Feb 2017 23:47:58 +0000

Maybe like the MPL?

"If you modify MPL code you must release your changes. If you keep your code as separate modules then they are not covered by the MPL." Okay, that's my paraphrase but that's pretty much how the MPL works.

Cheers,
Wol

RethinkDB source relicensed, donated to the Linux Foundation

Wol — Wed, 08 Feb 2017 23:44:53 +0000

Section 13 of v3.

Actually I might be thinking of v2, but v3 doesn't seem much clearer. It clearly permits using the covered work in conjunction with GPLv3.

But if I combine an Affero program with a proprietary back end to create a web-facing application, is this now a "modified version"? Does Affero apply to the back end as well as the front end? I don't know, and with v2 there were plenty of reports that people were scared that it might. That "exception for GPL" could easily be taken to imply that it does.

Cheers,
Wol

Affero not harmful

Cyberax — Wed, 08 Feb 2017 21:40:06 +0000

MongoDB _is_ corporate shareware. Pretty much all large companies that actually use it have a commercial license for it.

Besides, Mongo quite explicitly restricts the AGPL range: "To say this another way: if you modify the core database source code, the goal is that you have to contribute those modifications back to the community". I was assured by our lawyer that this interpretation is not necessarily the intent of the AGPL license and can't be applied to other projects.

I actually don't mind a good LGPL-like cloud license (A-LGPL?) that has a strictly limited scope of what's considered a derived work. And better legal implementation.

RethinkDB source relicensed, donated to the Linux Foundation

gowen — Wed, 08 Feb 2017 16:46:49 +0000

Thanks for those links - looking at the list of CNCF companies who paid to free the code, its even less surprising that the code was relicensed to make it more friendly to Web Service providers.

RethinkDB source relicensed, donated to the Linux Foundation

epa — Wed, 08 Feb 2017 11:49:08 +0000

I wouldn't like to be in a position where the software is running in production, but if I make any change to it I will be in breach of the licence unless I set up a way to download the modified code at the same time. If you plan to keep within the licence, and you accept that random fixes and changes to deployed software are sometimes necessary at short notice, you have to plan to maintain a download link for the particular code you're running.

Affero not harmful

ncm — Wed, 08 Feb 2017 05:55:55 +0000

MongoDB is licenced under Affero, and seems to be used a fair bit. At least, its monthly download rate is in the mid 10^5s, and it just got reliably linearizable durable distributed writes, which depends on quite a lot of sustained developer attention. It seems like some other reason is needed to explain why RethinkDB didn't end up driving a growing business.

It might be a better question why a project takes off than why it falters, because faltering is the usual outcome. But not studying why projects falter might ensure that yours will. Licenses don't seem to be among the main reasons either way.

RethinkDB source relicensed, donated to the Linux Foundation

andrewsomething — Tue, 07 Feb 2017 23:37:51 +0000

There's more details in this post by Bryan Cantrill who is on the Technical Oversight Committee at the Cloud Native Foundation. Looks like it was the Linux Foundation itself (via the CNCF) that re-licensed it.

https://www.joyent.com/blog/the-liberation-of-rethinkdb

RethinkDB source relicensed, donated to the Linux Foundation

aggelos — Tue, 07 Feb 2017 12:13:23 +0000

If it's quite easy to argue, would you kindly do so?

RethinkDB source relicensed, donated to the Linux Foundation

oldtomas — Tue, 07 Feb 2017 10:47:17 +0000

> toxic waste

Wow. As always even-headed and insightful comments when it comes to free software licensing. Just wow.

RethinkDB source relicensed, donated to the Linux Foundation

Wol — Tue, 07 Feb 2017 10:19:10 +0000

> Does this mean that ASF has gotten more discerning about accepting abandonware?

Has the ASF even been involved? Do they even know anything about it?

Using the Apache licence has nothing whatever to do with the Apache Software Foundation. It would have been nicer if they'd chosen the Mozilla licence (which allows closed add-ons to an open source base, but forbids closing the original open source). But it's their code, their choice.

And anyway, the whole point of the story is it's not abandonware. A group of Open Source people "bought" a defunct codebase because they actually wanted it. That's not abandonware in my book :-)

Cheers,
Wol

RethinkDB source relicensed, donated to the Linux Foundation

Wol — Tue, 07 Feb 2017 10:13:40 +0000

The big problem is that it's quite easy to argue that, if you use AGPL software, you need to make the *entire* *stack* available under the (A)GPL. Bit tricky if you're using MS SQL-Server as your db back end ...

Cheers,
Wol

RethinkDB source relicensed, donated to the Linux Foundation

lmb — Tue, 07 Feb 2017 08:42:27 +0000

For me, the AGPLv2 is an imperfect way of addressing the problem that "making software available" is no longer (semi-)identical to "distribution", and that in a cloud world, the GPL family of products no longer guarantees the user any freedom (with regard to the code).

RethinkDB source relicensed, donated to the Linux Foundation

njs — Tue, 07 Feb 2017 01:28:57 +0000

RethinkDB is by all accounts a pretty impressive piece of tech. It's one of the few "distributed databases" to actually live up to the name in Aphyr's tests: https://aphyr.com/posts/329-jepsen-rethinkdb-2-1-5

Compare to MongoDB, RethinkDB's most direct competitor: https://aphyr.com/tags/MongoDB

Their post-mortem is also worthwhile reading: http://www.defstartup.org/2017/01/18/why-rethinkdb-failed...

The CNCF (i.e., these folks: https://www.cncf.io/about/members) paying off the defunct company's creditors to relicense the code is a pretty extraordinary step. (The only precedent I can think of is the crowdfunding campaign that freed Blender?) This should give some idea about the value that at least some people perceive in it.

RethinkDB source relicensed, donated to the Linux Foundation

pabs — Mon, 06 Feb 2017 23:28:32 +0000

Those hoops only kick in if you actually modify the software, which normal deployments rarely need to.

RethinkDB source relicensed, donated to the Linux Foundation

Cyberax — Mon, 06 Feb 2017 19:50:34 +0000

It's a sign that AGPL is recognized as a toxic waste that nobody wants to touch. It's fine as a front for dually licensed "corporate shareware" products but nothing else.

RethinkDB source relicensed, donated to the Linux Foundation

tartley — Mon, 06 Feb 2017 19:23:16 +0000

FWIW, It's not just new json documents, it's new results to any arbitrary query, and the query language is powerful (e.g. like Mongo, unlike Cassandra)

RethinkDB source relicensed, donated to the Linux Foundation

joib — Mon, 06 Feb 2017 19:13:56 +0000

Indeed, although CNCF which apparently was the go-between in this case, is recommending the ASL2: https://www.cncf.io/blog/2017/02/01/cncf-recommends-aslv2

RethinkDB source relicensed, donated to the Linux Foundation

andresfreund — Mon, 06 Feb 2017 18:26:01 +0000

It's also very vaguely worded for anything that's not directly powering a website.

RethinkDB source relicensed, donated to the Linux Foundation

mdolan — Mon, 06 Feb 2017 17:44:59 +0000

The LF supports projects of all OSI-approve open source licenses, including many using copyleft GPL/LGPL/EPL/MPLv2 licenses. The communities and copyright owners pick the project licenses, not the Foundation. Bryan Cantrill posted a blog on why this community decided on a license change to ASLv2. https://www.joyent.com/blog/the-liberation-of-rethinkdb.

RethinkDB source relicensed, donated to the Linux Foundation

gowen — Mon, 06 Feb 2017 17:37:13 +0000

Not really. It's a sign that the "application provider" part of Affero GPL was a key part of the strategy in monetizing their software. It increased the sharing obligations for any potential competitors. If you're in the web services business, it helps to impose upon other web service businesses. Once you're out of the web services business, all you're doing is excluding Google and other anti-Affero types from using your software.

RethinkDB source relicensed, donated to the Linux Foundation

jhoblitt — Mon, 06 Feb 2017 17:34:19 +0000

Does this mean that ASF has gotten more discerning about accepting abandonware?

Why does a pub-sub filtering model for new json documents require an entirely new storage backend?

RethinkDB source relicensed, donated to the Linux Foundation

epa — Mon, 06 Feb 2017 16:24:46 +0000

The Affero GPL is a bit more than strong copyleft; it's extra-strength, with its hoops you must jump through to deploy the software on a public-facing website. This may be a Good Thing or a Bad Thing, but clearly it's a step beyond the GNU GPL and other traditional copyleft free licences.

RethinkDB source relicensed, donated to the Linux Foundation

pboddie — Mon, 06 Feb 2017 16:20:32 +0000

Of course: s/proprietary/permissive :-/

RethinkDB source relicensed, donated to the Linux Foundation

pboddie — Mon, 06 Feb 2017 16:19:34 +0000

Or maybe they relicensed to the Apache licence and then threw the code over the wrong wall. But I suspect that it is indeed a sign of the times: everybody avoids dealing with those awkward licence violation suspicions, at least until one of the members manages to fail to clear the much lower (but still not ground-level) bar stipulated by the terms of some proprietary licence or other.

Link

excors — Mon, 06 Feb 2017 16:14:29 +0000

I get a 404, unless I access it with "Pragma: no-cache" (e.g. shift+reload in web browser) in which case it works fine and shows the page, but then the next normal reload fails with 404 again.

The responses say e.g. "X-Served-By: cache-lhr6320-LHR" (number varies), which looks like a London part of the Fastly CDN, so I guess there's a problem there.

RethinkDB source relicensed, donated to the Linux Foundation

mstone_ — Mon, 06 Feb 2017 15:51:53 +0000

404 here also. Broken CDN?

RethinkDB source relicensed, donated to the Linux Foundation

lmb — Mon, 06 Feb 2017 15:50:34 +0000

It's a sign of the times that a project drops a strong copyleft license and then joins the Linux Foundation, instead of adopting one.

Link

xav — Mon, 06 Feb 2017 15:40:32 +0000

Works for me.

Link

corbet — Mon, 06 Feb 2017 15:36:05 +0000

Weird, the link works fine for me..?

RethinkDB source relicensed, donated to the Linux Foundation

elopio — Mon, 06 Feb 2017 15:29:59 +0000

The link is 404.