The bracketing was introduced to reduce the DDOS attack surface and increase the cache hit ratio. This means that we could in theory do all the magic of bracketing in the varnish (to keep the cache rate high), or we could force the clients to do the logic. The problem with Varnish approach is that it puts business-level logic into Varnish's brittle C-style configs.
On Thu, Sep 17, 2015 at 11:58 PM, Brion Vibber <bvib...@wikimedia.org> wrote: > Awesome sauce! Congrats to everyone who's been working on this. > > > On Thu, Sep 17, 2015 at 12:26 PM, Tomasz Finc <tf...@wikimedia.org> wrote: > > > == In Depth == > > > > Tiles are served from https://maps.wikimedia.org, but can only be > accessed > > from any subdomains of *.wmflabs .org and *.wikivoyage.org. > Kartotherian > > can produce tiles as images (png), and as raw vector data (PBF Mapbox > > format or json): > > > > .../{source}/{zoom}/{x}/{y}[@{scale}x].{format} > > > > Just a note -- the scale factor is for high-density displays, which are now > standard on most phones and increasingly common on laptops (1.5x is common > on small Windows laptops with 1080p displays). However the available scale > factors are hardcoded, so you can't just take an arbitrary device scale > factor (window.devicePixelRatio in HTML5) and feed it in, as it might not > match and you'll get HTTP errors out. > > I've got a provisional patch in for the example front-end which manually > brackets to the available settings: > https://github.com/kartotherian/kartotherian/pull/13 > > It'd be awesome to either expose the available scaling factors as a list > via JSON API, or move the bracketing logic into the server side so you can > send a query with your actual scale factor and get back one that will work. > > (If available scaling factors depend on the layer source being viewed, this > might be more complicated.) > > > > We would like to thank WMF Ops (especially Alex Kosiaris, Brandon Black, > > and Jaime Crespo), services team, OSM community and engineers, and the > > Mapnik and Mapbox teams. The project would not have completed so fast > > without you. > > > > Seconded. :) > > -- brion > _______________________________________________ > Wikitech-l mailing list > Wikitech-l@lists.wikimedia.org > https://lists.wikimedia.org/mailman/listinfo/wikitech-l > _______________________________________________ Wikitech-l mailing list Wikitech-l@lists.wikimedia.org https://lists.wikimedia.org/mailman/listinfo/wikitech-l
