I'm not sure if people are really confused about this or sowing FUD. Using Elasticsearch to search your own webapp is not providing Elasticsearch as a service. It's using Elasticsearch to provide functionality in your application.
Providing Elasticsearch as a service means allowing people to upload their own data and giving them an Elasticsearch instance to search it.
There's some grey area where it's a question if you're providing an application with a search feature or just hosting Elasticsearch. Like if you provide a way to upload logs and then search them that's Elasticsearch as a service. But if you provide an automated upload, is that enough?
> ...if you provide a way to upload logs and then search them that's Elasticsearch as a service
Yes, and if you let your internal company blogging platform ping a service upon every new post, which then feeds that post into Elastic so blog posts across your company are searchable?
I suspect one way to avoid this would be “buy a commercial license” (or use Amazon’s fork if you’re so minded), but if you’re using Elastic’s open source offerings — I’d be careful about licensing anything under SSPL, whatever your intentions are.
It can be, they just chose not to (with ulterior motives or not, I cannot say.)
For my side project, I am using a dual-licensed MIT/Apache (your choice) but with an exclusion which prohibits companies like AWS from offering it alone as a service. Here's a copy of the (quite human-readable) license:
I think a more charitable interpretation of Elastic's motives in the re-licensing would be to view them the same as your motives for your side project -- allow free use to anyone except those wanting to offer it as a hosted service. You say that you've licensed your side project with MIT and Apache2 but with an exclusion. In other words, it's neither MIT nor Apache2 and it's unclear how your exclusion would hold up legally (hopefully well!). At Elastic's scale, uncertainty over a license is too risky, so I'm sure they paid their lawyers $$$ to ensure that the SSPL would hold up in the scenarios that were important to them.
But I think it's unfortunate that companies end up with licenses like SSPL which are lengthy, not legible to non-lawyers (see this thread) and more importantly ambiguous in favor of the SSPL-software-provider. It's only natural, that's what lawyers are hired to do, after all! But I think there are other options (be ambiguous in favor of the opposing party, or build upon existing licenses)
Providing Elasticsearch as a service means allowing people to upload their own data and giving them an Elasticsearch instance to search it.
There's some grey area where it's a question if you're providing an application with a search feature or just hosting Elasticsearch. Like if you provide a way to upload logs and then search them that's Elasticsearch as a service. But if you provide an automated upload, is that enough?