The way Elasticsearch is going though looks promising. With sorted indices, single mapping type and the other changes we might give it another try after switching to Algolia.
Is there a safe way now to query Elasticsearch directly without the need to go via proxy scripts on the server? This just adds so much overhead to the queries compared to Algolia.
I can not give a timeframe, but it is one of the top features on the ES roadmap. :)
Source: I am an engineer working on this feature.
This works pretty well already if you are running on your own hardware and have a good network. We've been running a three data center setup across the US for four years. Next year we may extend it across the Atlantic.
https://greg.blog/2014/01/09/scaling-elasticsearch-part-1-ov...
But querying from a publicly facing front end would be a poor idea - would you expose a database directly to the front end?
It is a fantastic idea to call the index directly from the frontend and could be solved with a read only type of index or api key with read only scope.
The current design with an unnecessary security layer outside of Elasticsearch is a poor idea adding too much administrative overhead and ridiculous latency.
More charitably, I can understand why they felt the need to make a hard break, but difficult upgrades plus fast release cycle means a fair bit of friction.
The no downtime upgrades will be nice, but on a big production system, I wouldn't feel comfortable upgrading major versions every 6 months.
It feels from the discussion of the github issues that this was something that had caused some elastic developers pain and they decided to kill it.
There were two fundamental problems: 1) types had different mappings which was confusing since internally it's the same index and there is only one mapping. 2) for the use case where you have one type per index, you still had to arbitrarily create a "type".
It could have been done by: 1) making the mapping definition only at the index level - there's no such thing as a mapping for a type (this is how it works internally anyway.) 2) with a "type" field being optional and specified via a query string instead of url path. This would have left all the internals alone. Eg, there could have still be an internal meta "_type" field which would have had the default value of "default" or something. For those people that needed multiple types, specifically for more complex parent-child, they still could have done it.
The current approach is far more complicated because the have to change the internals to support both the new and old way during the transition and deal with a lot of internal things breaking because everything expects a "_type". You can checkout the github issues and see the work involved.
Lots of folks will be mad, but removing multiple mapping types is a nice change too. It was a feature that never really made sense. Index-per-type was always the better strategy, even going back to the 0.23 days.
As others in this thread will no doubt point out though - the ES folks are moving awfully fast. I still support 1.7.5 clusters that will take heroic efforts to update. I'd love to use the new features on those clusters, but there simply isn't a valid business case to take on the risk. This isn't like small NPM packages that you can update on a whim - some of these systems require terabytes of re-indexing to upgrade :/