Wikidata For Wikimedia Projects/Projects/cache createSchemaElement

Tracked in Phabricator:
Task T352019

Improve article loading time by caching SkinAfterBottomScriptsHandler::createSchemaElement

Background

Every Wikipedia article page contains a JSON-LD block in its HTML-source. JSON-LD is used to structure linked data in article pages for better search engine and third-party data consumption.
Currently, when building the JSON-LD schema, two database queries are executed:

TermLookup::getDescription: Fetches the description of the associated entity (possibly from Wikidata).
RevisionLookup::getFirstRevision: Retrieves the first revision of the article.

The Problem

These queries contribute significantly to the request time, with building the JSON-LD schema taking ~5% of the total request time when loading an article page.

The Solution

We are investigating if caching the results of TermLookup::getDescription and RevisionLookup::getFirstRevision will improve article loading time by avoiding the re-execution of these queries on every request.

Next Steps

We are currently investigating the following sub-tasks to improve performance for this task:

T379169: Cleanup service wiring (declined)
T379170: Create getFirstRevisionTimestamp function in Revision Store.

Create getFirstRevisionTimestamp function in Revision Store

In SkinAfterBottomScriptsHandler::createSchema, a resource-intensive functiongetFirstRevision is invoked to retrieve all revisions, sort them by date and ID, and select the oldest.
However, createSchema only requires the creation timestamp, not the full revision data.

This can be optimized, by directly querying the minimum timestamp (MIN(rev_timestamp)) from the revisions table.
This approach would simplify the process and avoid executing unnecessary selection and sorting operations, eliminating the getTimestamp helper function in createSchema.

By implementing a a new function, getFirstRevisionTimestamp the earliest revision timestamp will be more efficiently retrieved.