[IDV #EAV-659597]: Error with URL interface when trying to read GRIB file

hi Jess-

> We had a user trying to read a GRIB file using the URL chooser and
> received an error message.  Both McIDAS-V and IDV produce this error.
> If I save the file and load it in via the "Files" chooser, it works
> fine.  I also tried removing the file name and simply loading in the
> directory the file was located into the URL chooser and that worked fine.

For this last part, is the from local disk?  It shouldn't work from the
web server at all unless I'm not understanding what you did.

> Is this problem due to the file name?

No.  It looks like the server isn't set up to handle range requests
which are needed to create the grid indexes and read the data.

In general, you should not use HTTP to access grib files.  Even when
it works, the access is very slow.  It is best to place these behind
a THREDDS Data Server or serve from local disk.

> His file is located here:
> 
> http://www.ssec.wisc.edu/~daves/chop.pgbanl.fnl.2004081000
> 
> This is the error message he received:
> 
> ******************
> Stack trace:
> java.io.IOException: Server does not support Range requests, code= 200
> at
> ucar.unidata.io.http.HTTPRandomAccessFile.read_(HTTPRandomAccessFile.java:176)
> at ucar.unidata.io.RandomAccessFile.readBuffer(RandomAccessFile.java:335)
> at ucar.unidata.io.RandomAccessFile.seek(RandomAccessFile.java:323)
> at ucar.grib.grib1.Grib1Input.scan(Grib1Input.java:184)
> at ucar.grib.grib1.Grib1Indexer.writeFileIndex(Grib1Indexer.java:91)
> at
> ucar.nc2.iosp.grib.GribServiceProvider.writeIndex(GribServiceProvider.java:198)
> at
> ucar.nc2.iosp.grib.GribServiceProvider.getIndex(GribServiceProvider.java:169)
> at ucar.nc2.iosp.grib.GribServiceProvider.open(GribServiceProvider.java:94)
> at ucar.nc2.NetcdfFile.<init>(NetcdfFile.java:1104)
> at ucar.nc2.NetcdfFile.open(NetcdfFile.java:617)
> at ucar.nc2.NetcdfFile.open(NetcdfFile.java:314)
> at ucar.nc2.dataset.NetcdfDataset.openOrAcquireFile(NetcdfDataset.java:581)
> at ucar.nc2.dataset.NetcdfDataset.openDataset(NetcdfDataset.java:338)
> at ucar.nc2.dataset.NetcdfDataset.acquireDataset(NetcdfDataset.java:417)
> at ucar.nc2.dataset.NetcdfDataset.acquireDataset(NetcdfDataset.java:393)
> at ucar.nc2.dt.grid.GridDataset.open(GridDataset.java:72)
> at
> ucar.unidata.data.grid.GeoGridDataSource.doMakeDataSet(GeoGridDataSource.java:987)
> at
> ucar.unidata.data.grid.GeoGridDataSource.getDataset(GeoGridDataSource.java:1009)
> at
> ucar.unidata.data.grid.GeoGridDataSource.initAfterCreation(GeoGridDataSource.java:436)
> at ucar.unidata.data.DataManager.createDataSource(DataManager.java:1353)
> at
> ucar.unidata.idv.IntegratedDataViewer.createDataSource(IntegratedDataViewer.java:1855)
> at
> ucar.unidata.idv.IntegratedDataViewer.makeDataSource(IntegratedDataViewer.java:1772)
> at
> ucar.unidata.idv.IntegratedDataViewer.makeDataSource(IntegratedDataViewer.java:1706)
> at
> ucar.unidata.idv.IntegratedDataViewer.handleAction(IntegratedDataViewer.java:1560)
> at
> ucar.unidata.idv.IntegratedDataViewer.handleAction(IntegratedDataViewer.java:1492)
> at ucar.unidata.idv.chooser.UrlChooser.loadURLInner(UrlChooser.java:250)
> at ucar.unidata.idv.chooser.UrlChooser.loadURL(UrlChooser.java:222)
> at ucar.unidata.idv.chooser.UrlChooser.doLoadInThread(UrlChooser.java:269)
> at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
> at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
> at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
> at java.lang.reflect.Method.invoke(Unknown Source)
> at ucar.unidata.util.Misc$2.run(Misc.java:1010)
> at ucar.unidata.util.Misc$3.run(Misc.java:1038)
> 
> Thanks,
> 
> ~Jess
> 
> 


Ticket Details
===================
Ticket ID: EAV-659597
Department: Support IDV
Priority: Normal
Status: Open