I was wondering about caching OSM raw data but wasn’t able to find sth. yet.
In the process of search for such i also came across the API 0.6 description, and had a few ideas based on the limited view i got from that.
So take this as a simple dump of thoughts that may or may not be useful.
The ideal tool i was looking for would basically be the same as a caching web proxy, a datastore that would take requests in exactly the same way as an OSM server and could hence be used by any client as a replacement for an OSM server. When it was queried by a client it would check if requested data has been retrieved from OSM servers before and would download fresh data or serve a copy saved from a previous query.
I think geo data lends itself well for verifying if local cache data is current in an efficient way.
All data within a tile of a raster could be checksummed (on each change in the tikle) on the main OSM server and this tile object be tagged with the checksum. Using the checksum, the cache could verify if local data is current with low impact on the server.
Would such be a useful addition to OSM/API ?