If you read the Elastic License, it's actually worse than Mongo & Redis -- you can't modify it and use it for anything other than testing. You can basically install & use it only (definition of License, then the restrictions sections); if your testing uncovers something wrong... what are you supposed to do, under the terms of their license?
Comparing Lucene to Elasticsearch is very apples to oranges, in my opinion. It's like if MySQL did something people didn't like and the answer was "Discover InnoDB".
Sure, Lucene might be all you need, if all you need is some basic freetext search on a small set of data that fits on a single machine.
Though maybe you misspoke and meant to say "Discover Solr"...
Hm... Nope, ElasticSearch is a good entry point into Lucene. As your software needs grow, you may discover the benefits of going a level below. Start with ELK, then discover ElasticSearch, then use Lucene with your own way of distributing data over multiple machines if needed.
Personally, I never had to use more than 1 machine even for huge data sets (JFYI, Orbis and Wikipedia fit onto one bare metal server).
From the related AWS blog (so at least a few grains of salt):
>>This means that the majority of new Elasticsearch users are now, in fact, running proprietary software. We have discussed our concerns with Elastic, the maintainers of Elasticsearch, including offering to dedicate significant resources to help support a community-driven, non-intermingled version of Elasticsearch. They have made it clear that they intend to continue on their current path.
... maybe I'm misreading your comment, but it sounds like AWS tried to find a compromise, including contributing to upstream, and were shut down (and all their content about future contributing seems to say "we'll send it upstream, but it depends on whether Elastic accepts it," so seems to corroborate). It honestly seems like you get more certainty that everything you're using from AWS is open and will remain open, and Elastic is going to keep creating uncertainty / drive to proprietary source-available.
There is certainty around the open-source bits and the license - this is true. That said elastic the company has also seems to have brought the product a long way after becoming a company. Having a dedicated staff of engineers and developers behind a thing is helpful for that, and they should be able to make some money as part of this if we want to see future open source products advance similarly. (There is a difference too between consulting / services and money “at scale” - AWS is removing an at-scale component here)
That said, I also totally understand disagreements with Elastic’s decisions on charging for security, etc and why that causes concern. As a user I wish I wasn’t staring a fork in the face and I’m hopeful things get back to equilibrium here soon as a single community.
