Hi, I thought I had found a nice way to keep a filtered planet extract (by geographic extent *and* specific tags, in my case bridges in the US) up-to-date by using osmconvert[1], osmupdate[2] and osmfilter[3]. This was going to be my workflow:
Setup steps: A1. Grab a planet file A2. Derive the extract using osmconvert bzcat /osm/planet/planet-latest.osm.bz2 | ./osmconvert - -B=/osm/poly/us.poly -o=/osm/planet/us.o5m A3. Filter the desired features into a new file osmfilter /osm/planet/us.o5m --keep= --keep-ways="bridge=" --out-o5m > /osm/planet/bridges.o5m A4. Use osmosis to import the initial filtered planet extract into PostGIS. Replication steps: B1. Update the planet extract: osmupdate /osm/planet/us.o5m /osm/planet/us-new.o5m -B=/osm/poly/us.poly B2. Filter the desired features into a second file, analogous to step A3 B3. Derive an osc file from the two filter files using osmconvert. osmconvert bridges.o5m bridges-new.o5m --diff -o=diffbridges.osc B4. Using osmosis --rxc --wpc, update the PostGIS database B5. Clean up I started testing this and quite soon I hit an error in step B4: SEVERE: Thread for task 1-rxc failed java.lang.NullPointerException Trying to load the osc file[4] into JOSM I got the same error. I can't be sure but I think this has to do with referential integrity issues caused by missing nodes outside the bounding polygon. The --complete-ways option in osmconvert is supposed to solve that, but is not available either when the input is STDIN (step A2) or when osmconvert is called from osmupdate (step B1). The first case could be solved by just getting the initial file via some other means. I don't know how to solve the second case within the context of this set of tools. Is that possible? Suggestions for an alternative toolchain to accomplish this? Back to osmosis for the entire process, sacrificing speed? Would I run into different problems? [1] https://wiki.openstreetmap.org/wiki/Osmconvert [2] https://wiki.openstreetmap.org/wiki/Osmupdate [3] https://wiki.openstreetmap.org/wiki/Osmfilter [4] This is the file that was created when testing the process and gave the errors: https://gist.github.com/8001978303cb1077d7c2 -- martijn van exel geospatial omnivore 1109 1st ave #2 salt lake city, ut 84103 801-550-5815 http://oegeo.wordpress.com _______________________________________________ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
