Developer FAQ

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This FAQ is for questions that developers for MediaWiki might ask. Most of these are culled from IRC. If you have a question related to using MediaWiki, see this FAQ.

Recommended readingEdit

See our MediaWiki virtual library (MVL) for virtual (PDF) and printable books (you can order printed versions on demand at your own costs).

Working on the codeEdit

How do I startEdit

See How to become a MediaWiki hacker.

API QuestionsEdit

Localization questionsEdit

Append "?uselang=qqx" to the end of a MediaWiki URL to see the message keys displayed on the page, not their localised messages.

Code QuestionsEdit

Can I schedule jobs to run at a later timeEdit

Yes, use the Job Queue.

How can I use the Job QueueEdit

See the UploadFromUrl.php for an example.

How can my extension set up a special pageEdit

See $wgExtensionAliasesFiles .

Other questionsEdit

My patch failed a Jenkins test; now what?Edit

See Manual:PHP unit testing. Fix the problem and run a test on your end, and when it passes, submit a new patch.

I'm getting this weird "Error: Invalid magic word" message for no reasonEdit

Try changing some stuff in your LocalSettings.php (e.g. disable some extensions) and give it another try. It might just randomly start working again. This seems to have something to do with caching. Another cause of this error can be if you have a parser functions extension that doesn't put the necessary element in the $magicWords array.

Why am I getting "Notice: Undefined offset" in Database.php?Edit

You probably messed up your join conditions.

How do I get my changes reviewed?Edit

Use git blame on the file(s) you changed to find out who has contributed to that/those file(s) in the past. Add more than one of those contributors as reviewers; those who are not interested can remove themselves. See also Gerrit/Code review/Getting reviews.

See alsoEdit