make_water_map cannot write temporary files on Windows machines

[jhkennedy]

As reported in our Gitter, running asf_tools.water_map.make_water_map on Windows results in a Permission Denied error when trying to write the water map rasters via GDAL.

Commands:

>>>  from asf_tools.water_map import make_water_map
>>> water_extent_raster = 'water_extent.tif'
>>> make_water_map(
...     out_raster=water_extent_raster, vv_raster=vv_raster, vh_raster=vh_raster, 
...     hand_raster='water_extent_HAND.tif', tile_shape=(100, 100), 
...     max_vv_threshold=-15.5, max_vh_threshold=-23., hand_threshold=15., hand_fraction=0.8,
... )

Stack trace:

RuntimeError Traceback (most recent call last)
Input In [18], in <cell line: 6>()
3 from asf_tools.water_map import make_water_map
5 water_extent_raster = 'water_extent.tif'
----> 6 make_water_map(out_raster=water_extent_raster, vv_raster=vv_raster, vh_raster=vh_raster,
7 hand_raster='water_extent_HAND.tif', tile_shape=(100, 100),
8 max_vv_threshold=-15.5, max_vh_threshold=-23., hand_threshold=15., hand_fraction=0.8)

File ~\Anaconda3\envs\asftools\lib\site-packages\asf_tools\water_map.py:270, in make_water_map(out_raster, vv_raster, vh_raster, hand_raster, tile_shape, max_vv_threshold, max_vh_threshold, hand_threshold, hand_fraction, membership_threshold)
267 water_map = np.ma.masked_less_equal(gaussian_array, gaussian_threshold).mask
268 water_map &= ~array.mask
--> 270 write_cog(str(outraster).replace('.tif', f'{pol}_initial.tif'), water_map, transform=out_transform,
271 epsg_code=out_epsg, dtype=gdal.GDT_Byte, nodata_value=False)
273 log.info(f'Refining initial {pol} water extent map using Fuzzy Logic')
274 array = np.ma.masked_where(~water_map, array)

File ~\Anaconda3\envs\asftools\lib\site-packages\asf_tools\composite.py:208, in write_cog(file_name, data, transform, epsg_code, dtype, nodata_value)
206 with NamedTemporaryFile() as temp_file:
207 driver = gdal.GetDriverByName('GTiff')
--> 208 temp_geotiff = driver.Create(temp_file.name, data.shape[1], data.shape[0], 1, dtype)
209 temp_geotiff.GetRasterBand(1).WriteArray(data)
210 if nodata_value is not None:

File ~\Anaconda3\envs\asftools\lib\site-packages\osgeo\gdal.py:1927, in Driver.Create(self, args, **kwargs)
1925 def Create(self, args, kwargs):
1926 r"""Create(Driver self, char const * utf8_path, int xsize, int ysize, int bands=1, GDALDataType eType=GDT_Byte, char options=None) -> Dataset"""
-> 1927 return _gdal.Driver_Create(self, args, *kwargs)

RuntimeError: Attempt to create new tiff file `C:\Users\james\AppData\Local\Temp\tmpgbz4o7hi' failed: Permission denied

[jhkennedy]

It's possible this is related to converting Path() objects to strings for GDAL via str() and may be resolved by switching to os.fspath:
OSGeo/gdal#1613 (comment)