Since I27485bba, prop=imageinfo does not find a page_id for redirects from a ForeignDBRepo. Thus, it uses "0" or the empty string for a page_id, as in https://en.wikipedia.org/w/api.php?format=jsonfm&action=query&titles=File:Convento_Cristo_Decemebr_2008-8.jpg&prop=imageinfo

And it gets worse if the query contains multiple such redirects, as it winds up throwing an exception: https://en.wikipedia.org/w/api.php?format=jsonfm&action=query&titles=File:Convento_Cristo_Decemebr_2008-18.jpg|File:Convento_Cristo_Decemebr_2008-8.jpg&prop=imageinfo

Gerrit changeset I0b298290 will fix this issue.

Version: 1.21.x
Severity: normal