{25a0cc1d} introduced a hard requirement that the API revision result contains a parentid.
However the MediaWiki documentation was not correct, and this value is only provided by API v1.16+.
https://www.mediawiki.org/w/index.php?title=API:Revisions&diff=1914811&oldid=1914810
As a result, that commit broke support for v1.14+.
The bug has been fixed, but the issue of how to support 1.14-15 remains open.
| Subject | Repo | Branch | Lines +/- | |
|---|---|---|---|---|
| Remove requirement for Revision.parentid to exist | pywikibot/core | master | +19 -7 |
Change 246183 had a related patch set uploaded (by John Vandenberg):
Remove requirement for Revision.parentid to exist
Change 246183 merged by jenkins-bot:
Remove requirement for Revision.parentid to exist
I'm wondering how we could add support for that on older wikis. In theory if we query revisions in order and have queried the next (or if reversed, the previous) revision we could use that id but might cause problem because of T91883: prop=revisions sorts by rev_id, not by rev_timestamp.
If we query using rvendid=[Page.revid]&rvdir=older&rvlimit=2, the first revision should be the parent?
It wouldnt be very efficient if parentid is needed for many Revisions, but this is for very old wikis, so I'd prefer bad performance with a simple algorithm rather than very complex code which has only marginal performance improvements and is likely to only be used infrequently.