Maintaining NeoWiki

This covers the upkeep an evaluation NeoWiki instance needs: rebuilding the graph and the current limitations to be aware of. For first-time setup, see installation.

Rebuilding the graph

NeoWiki stores its canonical data in MediaWiki revision slots and keeps a regenerable copy in Neo4j for querying. You can wipe and rebuild the Neo4j copy from the canonical slots at any time. From the MediaWiki root:

php maintenance/run.php NeoWiki:RebuildGraphDatabases

It re-saves every Subject from each page's latest revision. Run it to:

• Recover after a Neo4j wipe or restore.
• Fix drift, such as the stale Page.name values left by page moves.

Two things to plan around:

• It does not clear the graph first, so orphan nodes from a drifted projection can survive a rebuild. For a guaranteed-clean result, wipe the Neo4j data volume before rebuilding.
• It runs as a single sequential process with no batching or resume, so the time scales with the number of pages. Plan downtime on large wikis.

Upgrades

NeoWiki adds no database tables of its own, so an upgrade is a code swap plus MediaWiki's standard updater. Update the NeoWiki code, then run the updater from the MediaWiki root:

php maintenance/run.php update --quick

If the new version changes how data is stored in the graph, rebuild the projection afterwards so it matches.

NeoWiki is pre-release, so a new version can change the schema or data format with no migration path. Your evaluation data may not survive an upgrade, so be ready to rebuild it from scratch.

Current limitations

Two known limitations while NeoWiki is pre-release:

• Page moves do not update the graph. Moving or renaming a page leaves its Page.name in Neo4j stale until you rebuild. Tracked in #875.
• A Neo4j outage blocks writes. Edits, deletes, and undeletes fail while Neo4j is unreachable; only reads and queries keep working. Tracked in #877.