During previous incident (T159631) it would have made sense to invalidate tiles for a part of the globe (Tasmania in that case). We can do a varnish ban based on URL regexes, but this requires to generate the regex for the correct coordinates for all zoom levels (coordinates used for tiles are not lon/lat and change at each zoom level). It might be easier to expose HTTP headers with the lon/lat coordinates of the tile and use those headers for invalidation. Using xkey was suggested, but I'm not sure that xkey really match the problem at hand.
|Resolved||MaxSem||T159631 Tasmania is covered with water at z10+|
|Resolved||• Mholloway||T159977 create a process to invalidate an area of map tiles in varnish|
- Mentioned In
- T230511: Lake missing on map for some zoom values
T202201: Stale z9 map tile in Vietnamese
T160809: Burma is under water?
- Mentioned Here
- P7451 maps-tiles-ban.sh
T201772: maps.wikimedia.org is showing old vandalized version of OSM
T109776: Tilerator should purge Varnish cache
T159631: Tasmania is covered with water at z10+
I don't see that a regex is really a problem. You'd need one regex per zoom you want to invalidate (or combine them into one regex), but those regexes are simple, just saying that the x and y values have to between maximum and minimum values.
Rather than let this languish, let's consider P7451 the process (in conjunction with the area-targeted URL generation added in https://github.com/kartotherian/tilerator/commit/93e1b4ecc81a1dca6d16299296d4c133c8d3a19b, where applicable) and call this done.