How to create a json file with the names and attributes of a VIIRS L2 CLDPROP netcdf file using python 3 ?

Example of python 3 code to save in a json file the names and attributes of a VIIRS L2 CLDPROP netcdf file.

Table of contents

Read the file
Get all group names
Get names and attributes in each group
Save in a json file
Python script
References

Note: the json file created can be found here

Read the file

import netCDF4
import numpy as np
import json
import pprint

f = netCDF4.Dataset('CLDPROP_L2_VIIRS_SNPP.A2018046.1436.001.2019068074007.nc')

Get all group names

group_dic = f.groups.keys()

Get names and attributes in each group

data_json = {}

for group in group_dic:
    selected_group = f.groups[group]
    group_variables_dic = selected_group.variables.keys()
    data_group_json = {}
    for group_variables in group_variables_dic:
        attributes = selected_group.variables[group_variables]
        #----------#
        # Get variables attributes
        attributes_dic = {}
        try:
            if group == 'scan_line_attributes':
                attributes_dic['long_name'] = attributes.long_name
                attributes_dic['FillValue'] = int( attributes._FillValue )
                attributes_dic['valid_min'] = int( attributes.valid_min )
                attributes_dic['valid_max'] = int( attributes.valid_max )
                attributes_dic['units'] = attributes.units
                attributes_dic['shape'] = attributes.shape          
            if group == 'geolocation_data':
                attributes_dic['long_name'] = attributes.long_name
                attributes_dic['FillValue'] = int( attributes._FillValue )
                attributes_dic['valid_min'] = int( attributes.valid_min )
                attributes_dic['valid_max'] = int( attributes.valid_max )
                attributes_dic['units'] = attributes.units
                attributes_dic['shape'] = attributes.shape  
                attributes_dic['scale_factor'] = attributes.scale_factor
                attributes_dic['add_offset'] = attributes.add_offset
            if group == 'geophysical_data':
                attributes_dic['long_name'] = attributes.long_name
                attributes_dic['FillValue'] = int( attributes._FillValue )
                attributes_dic['valid_min'] = int( attributes.valid_min )
                attributes_dic['valid_max'] = int( attributes.valid_max )
                attributes_dic['scale_factor'] = attributes.scale_factor
                attributes_dic['add_offset'] = attributes.add_offset
                attributes_dic['units'] = attributes.units
                attributes_dic['shape'] = attributes.shape  
            if group == 'cloud_model_data':
                attributes_dic['long_name'] = attributes.long_name
                attributes_dic['FillValue'] = int( attributes._FillValue )
                attributes_dic['valid_min'] = int( attributes.valid_min )
                attributes_dic['valid_max'] = int( attributes.valid_max )
                attributes_dic['units'] = attributes.units
                attributes_dic['shape'] = attributes.shape  
                attributes_dic['description01'] = attributes.description01  
                attributes_dic['description02'] = attributes.description02  
                attributes_dic['description03'] = attributes.description03  
                attributes_dic['description04'] = attributes.description04  
                attributes_dic['description05'] = attributes.description05  
                attributes_dic['description06'] = attributes.description06                  
        except:
            pass

        data_group_json[group_variables] = attributes_dic

    data_json[group] = data_group_json

Save in a json file

with open('viirs_cldprop_l2_names_attributes.json', 'w') as fp:
    json.dump(data_json, fp, sort_keys=False, indent=4)

Python script

import netCDF4
import numpy as np
import json
import pprint

#----------------------------------------------------------------------------------------#
# Read file

f = netCDF4.Dataset('CLDPROP_L2_VIIRS_SNPP.A2018046.1436.001.2019068074007.nc')

#----------------------------------------------------------------------------------------#
# Read group names

group_dic = f.groups.keys()

#----------------------------------------------------------------------------------------#
# Get names and attributes in each group

data_json = {}

for group in group_dic:
    selected_group = f.groups[group]
    group_variables_dic = selected_group.variables.keys()
    data_group_json = {}
    for group_variables in group_variables_dic:
        attributes = selected_group.variables[group_variables]
        #----------#
        # Get variables attributes
        attributes_dic = {}
        try:
            if group == 'scan_line_attributes':
                attributes_dic['long_name'] = attributes.long_name
                attributes_dic['FillValue'] = int( attributes._FillValue )
                attributes_dic['valid_min'] = int( attributes.valid_min )
                attributes_dic['valid_max'] = int( attributes.valid_max )
                attributes_dic['units'] = attributes.units
                attributes_dic['shape'] = attributes.shape          
            if group == 'geolocation_data':
                attributes_dic['long_name'] = attributes.long_name
                attributes_dic['FillValue'] = int( attributes._FillValue )
                attributes_dic['valid_min'] = int( attributes.valid_min )
                attributes_dic['valid_max'] = int( attributes.valid_max )
                attributes_dic['units'] = attributes.units
                attributes_dic['shape'] = attributes.shape  
                attributes_dic['scale_factor'] = attributes.scale_factor
                attributes_dic['add_offset'] = attributes.add_offset
            if group == 'geophysical_data':
                attributes_dic['long_name'] = attributes.long_name
                attributes_dic['FillValue'] = int( attributes._FillValue )
                attributes_dic['valid_min'] = int( attributes.valid_min )
                attributes_dic['valid_max'] = int( attributes.valid_max )
                attributes_dic['scale_factor'] = attributes.scale_factor
                attributes_dic['add_offset'] = attributes.add_offset
                attributes_dic['units'] = attributes.units
                attributes_dic['shape'] = attributes.shape  
            if group == 'cloud_model_data':
                attributes_dic['long_name'] = attributes.long_name
                attributes_dic['FillValue'] = int( attributes._FillValue )
                attributes_dic['valid_min'] = int( attributes.valid_min )
                attributes_dic['valid_max'] = int( attributes.valid_max )
                attributes_dic['units'] = attributes.units
                attributes_dic['shape'] = attributes.shape  
                attributes_dic['description01'] = attributes.description01  
                attributes_dic['description02'] = attributes.description02  
                attributes_dic['description03'] = attributes.description03  
                attributes_dic['description04'] = attributes.description04  
                attributes_dic['description05'] = attributes.description05  
                attributes_dic['description06'] = attributes.description06                  
        except:
            pass

        data_group_json[group_variables] = attributes_dic

    data_json[group] = data_group_json


#----------------------------------------------------------------------------------------#
# Save in a json file

with open('viirs_cldprop_l2_names_attributes.json', 'w') as fp:
    json.dump(data_json, fp, sort_keys=False, indent=4)

References

Link	WebSite
netCDF4 module	unidata.github.io
Continuity MODIS-VIIRS Cloud Properties products available	ladsweb.modaps.eosdis.nasa.gov
Search for Product Files	ladsweb.modaps.eosdis.nasa.gov
CLDPROP_L2_VIIRS_SNPP - VIIRS/Suomi-NPP Cloud Properties	ladsweb.modaps.eosdis.nasa.gov
READING NETCDF4 DATA IN PYTHON	iescoders.com
Reading NetCDF files with Python	ceda.ac.uk
MODIS and VIIRS Cloud Properties: User Guide	modis-atmosphere.gsfc.nasa.gov
Continuity User Guides	modis-atmosphere.gsfc.nasa.gov
pprint	python doc
How to Get a List of Class Attributes in Python	blog.pythonlibrary.org

Hi, I'm Ben, the Founder of moonbooks.org. I work as a research scientist specializing in Earth satellite remote sensing, particularly focusing on Fire detection using VIIRS and ABI sensors. My areas of expertise include Python, Machine Learning, and Open Science. Feel free to reach out if you notice any errors on the site. I am constantly striving to enhance it. Thank you!