Last modified: 2014-02-12 23:53:43 UTC
Looking at the data coming in from https://meta.wikimedia.org/wiki/Schema:MobileBetaWatchlist, it appears that non-enwiki users are not being assigned event_userId. To quote Matt Flaschen: "It's probably time to move wgUserId into the core JavaScript interface." :)
This is properly a MobileFrontend bug. EventLogging doesn't know about user IDs.
Also, as a general note, we should consider using the extension name in extension-defined keys, so these sorts of dependencies are obvious. We ran into this with PostEdit too. Consider it a vendor prefix.
An easy solution from the data analyst perspective: for MobileFrontend schemas, log username rather than user ID, since it does appear to work globally (tested on tawiki and plwiki). We should replace the event_userId field in our upload error schema (https://meta.wikimedia.org/wiki/Schema:MobileWebUploads) with event_username, so we can weed out staff uploads and reliably measure unique users' uploads globally.
Durr, we're not currently logging userId in Schema:MobileWebUploads. I meant we should change it to username on Schema:MobileBetaWatchlist and add it to Schema:MobileWebUploads. Sorry, long day :)
Gerrit change Id0adb795567d4ba932104938f2793cdb4084883c adds the variable to core. Until that is deployed, Gerrit change Ie9daf89c0acadbe24f95d7d6f3dded5d82af109e adds the variable in MobileFrontend. Whether or not you need the latter is up to you.
https://gerrit.wikimedia.org/r/51292
Id0adb795567d4ba932104938f2793cdb4084883c (same one Ori mentioned above), which adds wgUserId to core (among other things) is merged. Given that, up to MobileFrontend whether to use user ID or username.
Changes got merged.