31 December 2019, Apache Solr™ 8.4.0 available

The Lucene PMC is pleased to announce the release of Apache Solr 8.4.0

Solr is the popular, blazing fast, open source NoSQL search platform from the Apache Lucene project. Its major features include powerful full-text search, hit highlighting, faceted search, dynamic clustering, database integration, rich document (e.g., Word, PDF) handling, and geospatial search. Solr is highly scalable, providing fault tolerant distributed search and indexing, and powers the search and navigation features of many of the world's largest internet sites.

Solr 8.4.0 is available for immediate download at: https://lucene.apache.org/solr/downloads.html

Note: The Apache Software Foundation uses an extensive mirroring network for distributing releases. It is possible that the mirror you are using may not have replicated the release yet. If that is the case, please try another mirror. This also goes for Maven access.

Please report any feedback to the mailing lists (https://lucene.apache.org/solr/community.html#mailing-lists-irc)

Solr 8.4.0 Release Highlights:

  • A new package management system was introduced in order to ease deploying plugins.
  • Better security with the out-of-the-box configuration.

A summary of important changes is published in the Solr Reference Guide at https://lucene.apache.org/solr/guide/8_4/solr-upgrade-notes.html. For the most exhaustive list, see the full release notes here https://lucene.apache.org/solr/8_4_0/changes/Changes.html or by viewing the CHANGES.txt file accompanying the distribution.  Solr's release notes usually don't include Lucene layer changes.  Lucene's release notes are at https://lucene.apache.org/core/8_4_0/changes/Changes.html

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  1. I would add the following under New Features:

    • A package management system for the installation and management of Solr plugins (see SOLR-13822 and SOLR-13662 for more details)

    Plus something about the security-related overhaul of the UI and default configs? Ishan ChattopadhyayaDavid Smiley?

  2. Mikhail Khludnev you added some really minor items.  The release announcement should just mention the "highlights" big items and important stuff worth mentioning.

    This is also a good place to mention we want to deprecate some things.

  3. Can we start adding a link to the Ref Guide section about the release to this? Since this is just highlights, I think we should point users at our official docs to get more information on how these changes will impact them and now that the Ref Guide is published at the same time as the release. The link doesn't even need to change from release-to-release.

  4. Sounds great Cassandra; just do that then please.  I confess I did not find easily what you refer to in the ref guide.  BTW I did notice some old documentation published about the PDF version and of the release process.  I suspect this needs to be purged out.  https://lucene.apache.org/solr/guide/8_3/about-this-guide.html

    I'm going to try to write the 8.4 release highlights in the next couple hours.  It will say nothing about "timeAllowed" (smile)

    1. I added a sentence, right before "You are encouraged to thoroughly read CHANGES.txt ..."

      I spend 2-4 days every release writing those notes - I review the issue, interpret what I view as often excessively technical and/or brief details from CHANGES.txt to provide details on the context and impact, and link to the documentation for each feature. In my not-very-humble (with regard to this) opinion, what I come up with is superior to the Upgrade Notes in CHANGES.txt and we should be touting it far more than we are.

      I've previously stated once or twice that I think we should abandon this process of making a wiki page of release notes and all this should go in the Ref Guide instead, and I still think that.

      1. Oh; wow I can see you put a lot of valuable effort into the Solr Reference Guide on this matter.  I thought  that it was only about upgrading but I can see it's not; it covers new stuff and thus isn't strictly about upgrading.  In light of this, I think I agree that we should just point to this.  My only hesitation is that the announcement here has zero information about this particular release; a user has to click links to get any information at all.  I suppose that's fine.  It'd be nice to have a succinct paragraph or two summarizing "highlights" (and as such be much shorter than what you wrote in the ref guide) and be true to the heading here.  Or we remove the heading if we don't.  Coming up with highlights takes effort and may lead to debates (e.g. is timeAllowed worthy) and we seem to be short on time overall.  I reshuffled some content on this page, and slimmed it down.  I think it's ready to blast out when Adrien is.

  5. Actually I think it's important to get users excited about this new release without requiring them to click a link. I added two items about the pagkage manager and security, what do you think?

  6. Hi Adrien,

    There were some wrong links about "Changes".
    The text is 8.4, but the link pointed to 8.3.
    I changed it to 8.4. (Lucene release note too)

  7. Looks great; thanks everyone!

    I noticed earlier the links were to the wrong version as well but thought it was deliberate because the new versions didn't work yet. Besides; I think this will only be copy-pasted to an email so and so maybe the actual links don't matter?