User:NNikkhoui (WMF)/Mediawiki Background Info/Redirects

Notes from Timo's helpful phab comment:

1. Redirects can link to not only a page, but a section of a page. Example: Mirall redirects to Allen_Institute#Mirall

In MediaWiki code, these redirects should resolve to a LinkTarget (which can point to a section of a page) as opposed to a PageIdentity (which can only link to the page itself)

2. When redirects are changed, they are purged from the CDN. This only happens if the redirects are actually viewed as page views. If the UI redirects without going through the normal pageview flow, those redirects are not purged. REST API and OpenSearch are cached for multiple hours.

3. Redirects have pageview stats which are generated from actual page views redirecting. If we skip the step of the user actually going to the redirect source page, and just auto-suggesting the redirect target page, we lose this data.