Hi René, Thank you for starting this thread.
On Wed, 2022-06-15 at 16:37 +0700, Rene Cordier wrote: > Hello James community! > > I would like to start a discussion regarding the upgrade of > ElasticSearch, hoping we can reach a consensus, as I spent quite a lot > of time on this already. > > As you know, the version 7.10 has reached EOL already, so we need to > migrate from it. > > Thus a while ago I started a very painful migration to ES 8.2 here: > https://github.com/apache/james-project/pull/1018 > > Before being rightfully reminded by Matthieu Baechler that ES 7.10 is > the last OSI-compliant version of ElasticSearch, before you know they > switched to a new license that's not really open source anymore... > > OpenSearch is indeed a fork of ES 7.10 using the Apache License, which > is definitely more in favor for adoption for the migration than ES 8. On > that, I totally agree. > > From then, with Benoit Tellier, we did our little extra research then. > > If we want to migrate from ES to OpenSearch, there is a few options on > the table actually: > > - solution 1: not modifying the ES7 code. Well it's possible, but you > can only use versions 1.x of OpenSearch (1.3.3 atm). However, from 2.x > version of OpenSearch, the support for es7 client has been dropped in > favor of their own clients. The best part for this solution is: it should not require anything else than changing the docker image reference. > > - solution 2: using the java high level rest client from OpenSearch > (https://opensearch.org/docs/latest/clients/java-rest-high-level/): That > client is a basic fork of the java high level rest client from ES. As > this client has been dropped in upper version of ES for a new client > (that you can see in the PR I did before: > https://github.com/apache/james-project/pull/1018), the fork is thus > identical. > Benoit did a little POC on it and it seems you only need to change the > imports and it works with OpenSearch 2.0 without issues (also said here > in their doc: > https://opensearch.org/docs/latest/clients/java-rest-high-level/#migrating-to-the-opensearch-java-high-level-rest-client) > > - solution 3: using the new java client > (https://opensearch.org/docs/latest/clients/java/). That client has been > forked from the new java client from ES probably at its beginnings, > before the change of license. In the POC I did here: > https://github.com/apache/james-project/pull/1051, you can see the > structure is very similar to the java client from ES, but with obviously > some changes or bugs as the fork went its way since when from the > original one. That migration is complicated honestly, but because I did > the one to ES then the remaining work is minimal as proven in the POC. > Just a few issues though encountered... (in the POC you can see them) > > I think solution 1 is IMO, not an option, as we probably want to migrate > to the latest version of OpenSearch as we are at it now. > > Solution 2 is very easy (replace dependencies and imports... nothing > more) and allows to use OpenSearch 2.0. > > I would say let's go with it if I didn't invest so much time migrating > to the new java client. Because this is the issue actually. Amazon > states that the java client is supposed to replace the high level one at > some point (like on forums, or the page of the github project > (https://github.com/opensearch-project/opensearch-java). It's a bit > blurry on really when the high level client would be dropped but I > wouldn't be surprised to see it on next major upgrade for example. > > So at some point we will have to migrate the client eventually... do we > try to do it now (solution 3) or do we do things simple for now > (solution 2) and keep the work done under the hood for the day the > migration is necessary? (cause a big chunk of it has been done I think). > > I'm honestly fine either way, but would love to hear what the community > has to say on the topic. > > Sorry it was long! But I hope I gave all the keys necessary to > understand our options here regarding this migration. > My point is: upgrading to ES 8 was triggered by "ES 7 is EOL". OpenSearch 1.x is basically a supported ES 7 and the code for ES 7 is supposed to work perfectly with OpenSearch 1.x. Instead of deleting the support for ES 7, we could just keep it and run tests against OpenSearch. Investment is very low and people don't have to switch to non- opensource ES 8 if they don't want to. If ever somebody has interest in migrating to OpenSearch 2, it can be migrated at this point. I would personally postpone the migration and go for solution 1. Regards, -- Matthieu --------------------------------------------------------------------- To unsubscribe, e-mail: server-dev-unsubscr...@james.apache.org For additional commands, e-mail: server-dev-h...@james.apache.org
