[patch] Download parent ways/relations unnecessarily downloads nodes repeatedly

[anonymous]

When selecting sevaral nodes of the same way and then "download parent ways/relations" JOSM downloads the same nodes many times.

What appears to happen is that JOSM for each node first (correctly) downloads all ways referencing that node. Then it goes on to download all nodes of the ways returned. However if you are trying to find all connected ways to another way and thus select all nodes of that way, josm will download all nodes in that way however many times as there are nodes in that way. So if e.g. you are trying to find connected ways/nodes in a 600 node way (in order to delete it and its nodes without conflicts), JOSM will download those 600 nodes 600 times instead of just downloading them once.

[lordsutch]

Patch for duplicate downloads

[lordsutch]

The attached patch ensures that nodes are only downloaded once, which should reduce the server load of the Download Ways/Relations... command substantially. (Server-side support for relations and ways referenced by a list of nodes would make this even more efficient.)

[bastiK]

        // Don't retrieve any nodes we've already grabbed
        nodes.removeAll(parents.getNodes());

Do you mean targetLayer.data instead of parents?

[lordsutch]

Do you mean targetLayer.data instead of parents?

Sure; that probably would be an even bigger improvement. (This is my first real hacking on JOSM, so I wasn't sure what layers were available in the code beyond those already used elsewhere in the .java file.)

[bastiK]

In [4094/josm]:

applied #5293 (patch by lordsutch) - Fix: Download parent ways/relations unnecessarily downloads nodes repeatedly