dannycochran
commented
8 years ago It is definitely possible and there's a number of ways you could achieve dynamic loading of data. It depends on what you want to do.
What kind of server are you running? Node? Python? Rails? Basically, you should send a request from the client that looks like this:
$.ajax({
url: '/wind_data',
data: {
timestamp: '2016070106', // this is July 1st, 2016 at 6 a.m. UTC-0 YYYYMMDDHH
millibars: 1000 // pressure altitude
}
});Then, let's say you had a nodeJS server, you'd do:
app.get('/wind_data', (req, res) => {
const timestamp = req.query.timestamp;
const millibars = req.query.millibars;
const url = `http://nomads.ncep.noaa.gov/cgi-bin/filter_gfs_1p00.pl?file=gfs.t00z.pgrb2.1p00.f000&lev_${millibars}_mb=on&var_UGRD=on&var_VGRD=on&dir=%2Fgfs.${timestamp}`;
// curl the data with node-curl
curl(url, function(err) {
// Then, use npm shell to run a shell command, converting the data with grib2json, this means
// you'd have to have grib2json installed on whichever machine is running the server.
shellCommand('grib2json gfs.t00z.pgrb2.1p00.f000 output.json');
res.json(output.json);
});
});This process would look similar with whichever server you have. grib2json is a fairly small library and doesn't have any modules for node, python, or ruby as far as I know, so you'll have to have your server run a shell command assuming that grib2json is installed on your machine.
If your server is in Java, however, it would be easier since the grib2json module is written in Java. Let me know if the above pseudo code makes sense and if you have any other questions, happy to help get you set up.
divyanshu-rawat
NgocHoang2017
subhadeep-maishal
First of all Great work . Now I wan to ask that the link that you have provided (https://raw.githubusercontent.com/dannycochran/windable/master/data/2016040900_700.json ) has data already data in JSON format but I want to ask is there any script that will automatically convert the data that I download from NOMADS to json format. In order to convert Grib2 to json I have already tried cambecc grib2json utility but it requires all the commands to be executed on terminal. I want to ask is it possible to write some script that will automatically convert grib2 format to json format.