Note: the above example applies to the mw1.21-wmf5 branch of the Wikibase modules, as of commit rEWBA24d8471add31.

To test for this bug, try the following:

Go to https://test2.wikipedia.org/wiki/Helium, open the edit page. There should be no (or just a few) interlanguage links.

The, click preview. More (>100) language links should be loaded from https://www.wikidata.org/wiki/Q560.

Note however that this only works as a test as long as the solution for bug 42187 isn't implemented. That will make it unnecessary to load the item on the client, for now. We *will* need that ability in a few weeks at the latest, though.

In eval.php, try this:

$row = new stdClass();
$row->old_text = "DB://cluster25/316188";
$row->old_flags = "utf-8,gzip,external";
Revision::getRevisionText( $row );

Apparently, when Chad tried this, it worked. Yet, if tried in a web request, it fails...

$ mwscript eval.php --wiki=test2wiki

var_dump( ExternalStore::fetchFromURL( 'DB://cluster25/316188' ) );

bool(false)
$

:-(

As brion remarked on IRC, the external store servers have a DB for each wiki. If you look at addWiki.php you can see how each cluster master has the new DB initialized for a new wiki. Also see storage/blobs.sql. In order to access text blobs saved from a foreign wiki, one would need to change getRevisionText() to pass down some optional wiki ID and change ExternalStore to except it. So if you know you are fetching a text for wikidatawiki that wiki ID could be passed in.

This is a case of some subtle global state (the wiki ID is assumed to be the current wiki ID).

(In reply to comment #3)

In eval.php, try this:

$row = new stdClass();
$row->old_text = "DB://cluster25/316188";
$row->old_flags = "utf-8,gzip,external";
Revision::getRevisionText( $row );

Apparently, when Chad tried this, it worked. Yet, if tried in a web request,
it
fails...

Works when run on wikidatawiki, not elsewhere.

fixed by Change I14a7ebb8: (bug 42948) $wiki parameter for getRevisionText().

Closed older resolved bugs as verified.