But if my proprietary SaaS only uses Grafana for monitoring but its key purpose is doing something else entirely, I can no longer use Grafana unless I also publish my SaaS under AGPLv3, right?
What if I release my own SaaS as AGPLv3? Do others, who rely on it, also have to license their software under AGPLv3? I think this kills many business cases.
>I can no longer use Grafana unless I also publish my SaaS under AGPLv3, right?
If you link to it directly from your code then yes, unless you're willing to pay Grafana for a commercial license (assuming they offer one or you can negotiate one with them). If you have Grafana running on your servers but you aren't using the code in your own applications then you're generally fine (the GPL is generally recognized as ending where a process ends). And that's the point of the GPL/AGPL, you get the code for free, with the only expectation being that you pass it on if you make any changes.
If your server runs Linux you don't have to distribute the source code of Linux to the users of the services running on it. If Linux was AGPL you would have to. And yet, you would not have to distribute the source of your closed source software running on the server.
You wouldn't, as system interfaces are specifically excluded as an AGPL enforcement domain. But if the Linux kernel was AGPL, you would have to supply the source code to your NFS clients, since those clients would be served directly by the kernel.
The only difference between GPL3 and AGPL3 is what constitutes distribution. With GPL3 you have to provide source to anyone you provide binaries. With AGPL3 you also have to provide source to anyone who uses the software remotely (eg a web app). Everything else, including the scope of what must be included in the source (modifications, linked software, but not software that talks over IPC, etc), is identical between GPL3 and AGPL3.
More specifically, the only difference between GPL and AGPL is section 13 (and the preamble summary). The rest of the license is word-for-word identical (save for the name).
https://www.gnu.org/licenses/agpl-3.0.en.html#section13
To expand on that, you have to offer to provide the source to "all users interacting with it remotely through a computer network". If you're using Grafana for monitoring your SaaSS app, then your users aren't interacting with Grafana, so you're fine.
If your SaaSS app surfaces a few small things from Grafana to the user, do you only have to open source the glue code, or the entire SaaSS application?
The entire application, to the extent that it's a single work under copyright law. If your app is a "mere aggregation" of e.g. grafana administration and other-service-administration components then maybe not.
If you're only using Grafana for monitoring but not distributing it to your users as part of your product then I don't think you need to make your own product AGPL.
I'm sure if I'm wrong I will find out very quickly, this is HN after all.
What if I release my own SaaS as AGPLv3? Do others, who rely on it, also have to license their software under AGPLv3? I think this kills many business cases.
Am I missing some key point?