[Tile-serving] [openstreetmap/osm2pgsql] Add tilesets to flex output allowing more flexible expire configuration (PR #1912)

[Jochen Topf]

1. Filenames: They are absolute. You can get filenames relative to the config file by using `osm2pgsq.config_dir`  which is automatically set in Lua scripts. If you don't want to hard code file paths in a config file, use [environment variables](https://osm2pgsql.org/doc/manual.html#accessing-environment-variables-from-lua).
2. Allowing for flexible expire based on knowledge of the style file is part of the reason for this PR. Because the expire to the different tilesets is based on table columns this works as long as you have geometries with different expire needs in different tables. If you have one large table with everything in it, this design can not help you there. I thought about doing this differently but that would have meant giving the user in Lua some way of deciding for each and every geometry how to expire it, i.e. which tileset to expire to and with which configuration. This would have made the configuration much more complex and slower (because there would be a lot more Lua logic involved). You only get  the full advantage of selectively re-rendering only some layers if the results doesn't end up in one large tile, but several tiles based only on some layers.

-- 
Reply to this email directly or view it on GitHub:
https://github.com/openstreetmap/osm2pgsql/pull/1912#issuecomment-1429310131
You are receiving this because you are subscribed to this thread.

Message ID: <openstreetmap/osm2pgsql/pull/1912/c1429310131 at github.com>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openstreetmap.org/pipermail/tile-serving/attachments/20230214/ee36ed54/attachment-0001.htm>