Re: [thredds] Accessing THREDDS from Java

Hi and thanks for the replies.

I've tried connecting with CdmRemote to your instance, works fine! I
noticed a slight pause on connect (I suppose that is tranfer of
headers..)

    String location =
"http://thredds-jumbo.unidata.ucar.edu/thredds/cdmremote/grib/NCEP/GFS/Global_0p25deg/Best";;
        ucar.nc2.stream.CdmRemote remoteNC = new
ucar.nc2.stream.CdmRemote(location);
        Variable var =
remoteNC.findVariable("Total_ozone_entire_atmosphere_single_layer");
        System.out.println(var.getDimensions());

   OUTPUT:
[time = 119;, lat = 721;, lon = 1440;]

At the time FeatureDatasetFactoryManager does not catch cdmremote
protocol, does it? Is it possible somehow cast CdmRemote to
GridDataset/GridDatatype to retrieve GridCoordSystem?

        Formatter errlog = new Formatter();
        FeatureDataset fdataset =
FeatureDatasetFactoryManager.open(FeatureType.GRID, location, null,
errlog);  //  Exception

I found [1] saying how to setup cdmremote, is that the right link if I
want to setup THREDDS locally with cdmremote enabled?

ProtoBuf.js seems very up to date. Maybe some day it will be merged
with protobuf repository. However, it is a communication framework. I
suppose building JavaScript lib for cdmremote will require substancial
efforts since Java-like functionality (Variable, Array etc.) will have
to be re-implemented on JavaScript.

[1] 
http://www.unidata.ucar.edu/software/thredds/v5.0/netcdf-java/reference/stream/CdmrFeature.html

2015-07-28 17:54 GMT+03:00 Christian Ward-Garrison <cwardgar@xxxxxxxx>:
> Hi Rich,
>
> So far, there's just the Java client. However, a Python client is under
> active development. There are currently no plans for a Javascript client.
>
> -Christian
>
> On Tue, Jul 28, 2015 at 5:15 AM, Signell, Richard <rsignell@xxxxxxxx> wrote:
>>
>> Christian & THREDDS enthusiasts,
>>
>> So cdmremote/ncstream uses protobuf for transport, right?
>>
>> So has anybody built a javascript library to access data via cdmremote?
>>
>> Seems like that would be a great match, as protobuf is recognized as
>> being a better choice than JSON for data-heavy web applications:
>>
>> http://blog.codeclimate.com/blog/2014/06/05/choose-protocol-buffers/
>>
>> and there are several existing protobuf libraries for JS, for example,
>> this one:
>> https://github.com/dcodeIO/ProtoBuf.js/wiki
>>
>> -Rich
>>
>> On Mon, Jul 27, 2015 at 9:10 PM, Christian Ward-Garrison
>> <cwardgar@xxxxxxxx> wrote:
>> > Actually, this [1] is a more helpful link for cdmremote — it points to
>> > TDS
>> > v5.0 documentation. At the bottom, it talks about client programs for
>> > the
>> > protocol.
>> >
>> > [1]
>> >
>> > http://www.unidata.ucar.edu/software/thredds/v5.0/netcdf-java/reference/stream/CdmRemote.html
>> >
>> > On Mon, Jul 27, 2015 at 7:06 PM, Christian Ward-Garrison
>> > <cwardgar@xxxxxxxx>
>> > wrote:
>> >>
>> >> Hi Antonio,
>> >>
>> >> Sorry for not getting to this sooner; we were all busy with the 2015
>> >> Training Workshop last week.
>> >>
>> >> You may want to take a look at cdmremote [1]. It's an experimental
>> >> protocol we've been developing that compares quite favorably to
>> >> OPeNDAP. In
>> >> terms of performance, "The java implementation of ncstream should be
>> >> (close
>> >> to) maximal I/O efficient." And yes, it is certainly possible for
>> >> NetCDF-Java to access a THREDDS server using cdmremote as long as that
>> >> server enables it as a data access service. Here [2] is an example on
>> >> one of
>> >> our servers.
>> >>
>> >> Cheers,
>> >> Christian
>> >>
>> >> [1]
>> >>
>> >> http://www.unidata.ucar.edu/software/thredds/current/netcdf-java/reference/stream/CdmRemote.html
>> >> [2]
>> >>
>> >> http://thredds-jumbo.unidata.ucar.edu/thredds/cdmremote/grib/NCEP/GFS/Global_0p25deg/Best?req=form
>> >>
>> >> On Tue, Jul 21, 2015 at 11:26 AM, Antonio Rodriges
>> >> <antonio.rrz@xxxxxxxxx>
>> >> wrote:
>> >>>
>> >>> Sorry for posting this question on the mail list, however I could not
>> >>> find the answer after googling.
>> >>>
>> >>> The THREDDS page [1] lists the supported protocols: "OPeNDAP, OGC WMS
>> >>> and WCS, HTTP, and other remote data access protocols."
>> >>> Also, it is noted that "The Netcdf-Java/CDM library reads NetCDF,
>> >>> OpenDAP, ..."
>> >>>
>> >>> My question is :
>> >>> 1) what are other protocols that are supported by TDS?
>> >>> 2) which protocol is the fastest? For example, has the lowest
>> >>> overheads in network I/O or creating output data, etc or their is no
>> >>> definite answer?
>> >>> 3) is it possible to use Netcdf-Java to access TDS using other
>> >>> supported protocols or Netcdf-Java can access TDS only via OpenDAP?
>> >>>
>> >>> Thanks
>> >>>
>> >>> [1] http://www.unidata.ucar.edu/software/thredds/current/tds/TDS.html
>> >>>
>> >>> _______________________________________________
>> >>> thredds mailing list
>> >>> thredds@xxxxxxxxxxxxxxxx
>> >>> For list information or to unsubscribe,  visit:
>> >>> http://www.unidata.ucar.edu/mailing_lists/
>> >>>
>> >>
>> >
>> >
>> > _______________________________________________
>> > thredds mailing list
>> > thredds@xxxxxxxxxxxxxxxx
>> > For list information or to unsubscribe,  visit:
>> > http://www.unidata.ucar.edu/mailing_lists/
>>
>>
>>
>> --
>> Dr. Richard P. Signell   (508) 457-2229
>> USGS, 384 Woods Hole Rd.
>> Woods Hole, MA 02543-1598
>
>



  • 2015 messages navigation, sorted by:
    1. Thread
    2. Subject
    3. Author
    4. Date
    5. ↑ Table Of Contents
  • Search the thredds archives: