Opened 13 years ago

Last modified 5 years ago

#17 reopened enhancement

adding option to only get "newer than" - objects

Reported by: steve@… Owned by: steve@…
Priority: minor Milestone: OSM 0.7
Component: api Version:
Keywords: Cc:

Description

An option to grab only those objects that are newer than a specific time would
enable clients to cache data performantly.

"newer than" must return all objects that changed since the given time, so a
last changed timestamp are needed for every object.

Either, the referencing objects of all changed objects are transfered as well.
Then this option is nice as stand alone for viewing only recent changes.

Or it really only transfer those objects that have changed, in which case the
performance is optimal for clients using caches.

Note, that for the second option, this cannot be done correctly with GPX, e.g.
it must be possible to transfer line segments without tracks or property-keys
without any object.
When using the second option with the XML scheme proposed in the wiki, it has to
be allowed, that objects are transfered without their referencing object before
(the clause "There must be no reference to an id, which has not been transfered
yet." is disabled)

Change History (7)

comment:1 Changed 13 years ago by tom@…

  • Type changed from defect to enhancement

comment:2 Changed 13 years ago by immanuel.scholz@…

Either, the referencing objects of all changed objects are transfered as well. Then
this option is nice as stand alone for viewing only recent changes.

Or it really only transfer those objects that have changed, in which case the
performance is optimal for clients using caches.

The second option is much more important. In fact, I think the former isn't necessary anyway if things like the planet.osm snapshot make the round..

comment:3 Changed 12 years ago by writetodan@…

for this to work, need to have sequential change IDs, as objects can share the same timestamp - i.e. need a version table (as there already is for ways).

comment:4 Changed 11 years ago by tom@…

See also #94 which asks for the same thing.

comment:5 Changed 6 years ago by Richard

  • Resolution set to fixed
  • Status changed from new to closed

Five years later, we have minutely diffs!

comment:6 Changed 6 years ago by woodpeck

  • Priority changed from major to minor
  • Resolution fixed deleted
  • Status changed from closed to reopened

Minutely diffs do not fix this particular issue.

comment:7 Changed 5 years ago by iandees

  • Milestone changed from OSM 0.5 to OSM 0.7

A newer-than arg to the map call might be interesting to help cut down on data transfer for clients.

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