tests.py

import re
import unittest
import subprocess
from srtm import get_elevation, get_file_name


'''
These elevation values were taken using gdallocationinfo command which is
a part of gdal-bin package. You can install it in Ubuntu (or derivatives)
using:
    sudo apt-get install gdal-bin
'''

TEST_DATA = [
    {
        'name': 'Mt. Everest',
        'lat': 27.988056,
        'lon': 86.925278,
        'filename': 'hgt/N27E086.hgt',
        # gdallocationinfo N27E086.hgt -wgs84 86.925278 27.988056
        'alt': 8840
    },
    {
        'name': 'Mt. Kanchanjunga',
        'lat': 27.7025,
        'lon': 88.146667,
        'filename': 'hgt/N27E088.hgt',
        # gdallocationinfo N27E088.hgt -wgs84 88.146667 27.7025
        'alt': 8464
    }
]


def get_elevation_from_gdallocationinfo(filename, lat, lon):
    output = subprocess.check_output([
        'gdallocationinfo', filename, '-wgs84', str(lon), str(lat)
    ])
    return int(re.search('Value: (\d+)', str(output)).group(1))


class TestSRTMMethods(unittest.TestCase):

    def test_get_elevation(self):
        for mountain in TEST_DATA:
            elevation = get_elevation(mountain['lat'], mountain['lon'])
            gdal_elevation = get_elevation_from_gdallocationinfo(
                mountain['filename'], mountain['lat'], mountain['lon']
            )
            self.assertEqual(elevation, gdal_elevation)

    def test_get_file_name(self):
        for mountain in TEST_DATA:
            filename = get_file_name(mountain['lat'], mountain['lon'])
            self.assertEqual(filename, mountain['filename'])


if __name__ == '__main__':
    unittest.main()