[OSM-dev] 0.6 API clarifications and corrections

[Frederik Ramm]

Hi,

> A single changeset can change an object from version 1->15, but in  
> that
> case, each of the changes within that changeset should still be  
> laid out
> in the changeset response, right? so one would be the change from 1- 
> >2,
> 2->3, ... 14->15? Or not?

Don't know.

The most usable type of response for the user would certainly be:

"As a result of this changeset, Object X was changed from state A to  
state B".

As a user, I am not interested in the 318 intermediate editing steps;  
I want to know the before and after versions of the object.

So if someone requests a list of all changes for one changeset, my  
suggestion would be to return:

* exactly two versions of each object changed in that changeset  
("before" and "after")
* only the "before" version for deleted objects
* only the "after" version for created objects

If an object is created and deleted within the same change set, do  
not return anything at all.

The one thing I am unsure about is whether this can be coded  
efficiently ;-) basically you have to retrieve the highest and  
smallest version number of each object linked to this changeset and  
then return the object with the highest version and the object with  
the version "smallest-1".

Bye
Frederik

-- 
Frederik Ramm  ##  eMail frederik at remote.org  ##  N49°00'09" E008°23'33"