[josm-dev] upload the same work several times

[Matthias Julius]

didier2020 <didier2020 at free.fr> writes:

> Le dimanche 22 juillet 2012 à 12:20 +0200, Dirk Stöcker a écrit :
>> On Sun, 22 Jul 2012, didier2020 wrote:
>> 
>> > my english is poor (sorry).
>> >
>> > users can load the same work several times like:
>> > http://www.openstreetmap.org/browse/changeset/12366293
>> > http://www.openstreetmap.org/browse/changeset/12366372
>> >
>> > can josm tell error to the user if
>> >   same number of node
>> > or same sumber of way
>> > or same number of way and node
>> > had allready uploaded during the same "session".
>> >
>> > it's difficult to detect that when it's done.
>> 
>> This is only possible, when for some reason uploading fails. And in this 
>> case it is very complicated to detect for JOSM what has been uploaded and 
>> what has not been uploaded.
>> 
>> In the long term this issue should be fixed, but it is not easy and 
>> happens seldom enough to be a major issue.
> thanks you anyway

Just to elaborate a bit more: When you create new objects in JOSM they
get temporary (negative) IDs. Then, when you upload the data JOSM sends
those IDs to the server. The server processes the data and if it doesn't
see any problems with it it assigns a permanent ID to each object with a
negative one and sends all of these new IDs back to JOSM. JOSM in turn
updates its objects in memory with the new IDs it got back from the
server. This way JOSM knows the new data made it successfully into the
database.

For a larger amount of data the server processing stage might take quite
a while. If during that time the internet connection of the client
fails, the user hits Abort, there is a timeout, or anything else happens
that causes JOSM to loose its connction the server might accept the data
and load it into the database and JOSM won't know about it. On the next
upload JOSM will upload the same data again.

Therefore, it is a very good idea in case an upload fails or gets
aborted to update the local dataset before trying to upload
again. JOSM's Validator should then warn you about duplicate objects.

Matthias