Commit d72f8862 authored by Claude Paroz's avatar Claude Paroz
Browse files

Fixed #25072 -- Prevented GDALRaster memory to be uncollectable 

Setting GDALRaster.bands as a cached property was creating a circular
reference with objects having __del__ methods, which means the memory
could never be freed.
Thanks Daniel Wiesmann for the report and test, and Tim Graham for the review.
parent 0b02ce54

django/contrib/gis/gdal/raster/band.py

+21 −0
Original line number Diff line number Diff line 
from ctypes import byref, c_int



from django.contrib.gis.gdal.base import GDALBase

from django.contrib.gis.gdal.error import GDALException

from django.contrib.gis.gdal.prototypes import raster as capi

from django.contrib.gis.shortcuts import numpy

from django.utils import six

from django.utils.encoding import force_text

from django.utils.six.moves import range



from .const import GDAL_INTEGER_TYPES, GDAL_PIXEL_TYPES, GDAL_TO_CTYPES
@@ -148,3 +150,22 @@ class GDALBand(GDALBase): 
                return list(data_array)

        else:

            self.source._flush()





class BandList(list):

    def __init__(self, source):

        self.source = source

        list.__init__(self)



    def __iter__(self):

        for idx in range(1, len(self) + 1):

            yield GDALBand(self.source, idx)



    def __len__(self):

        return capi.get_ds_raster_count(self.source._ptr)



    def __getitem__(self, index):

        try:

            return GDALBand(self.source, index + 1)

        except GDALException:

            raise GDALException('Unable to get band index %d' % index)

django/contrib/gis/gdal/raster/source.py

+6 −12
Original line number Diff line number Diff line
@@ -6,7 +6,7 @@ from django.contrib.gis.gdal.base import GDALBase 
from django.contrib.gis.gdal.driver import Driver

from django.contrib.gis.gdal.error import GDALException

from django.contrib.gis.gdal.prototypes import raster as capi

from django.contrib.gis.gdal.raster.band import GDALBand

from django.contrib.gis.gdal.raster.band import BandList

from django.contrib.gis.gdal.raster.const import GDAL_RESAMPLE_ALGORITHMS

from django.contrib.gis.gdal.srs import SpatialReference, SRSException

from django.contrib.gis.geometry.regex import json_regex
@@ -15,7 +15,6 @@ from django.utils.encoding import ( 
    force_bytes, force_text, python_2_unicode_compatible,

)

from django.utils.functional import cached_property

from django.utils.six.moves import range





class TransformPoint(list):
@@ -108,9 +107,10 @@ class GDALRaster(GDALBase): 


            # Set band data if provided

            for i, band_input in enumerate(ds_input.get('bands', [])):

                self.bands[i].data(band_input['data'])

                band = self.bands[i]

                band.data(band_input['data'])

                if 'nodata_value' in band_input:

                    self.bands[i].nodata_value = band_input['nodata_value']

                    band.nodata_value = band_input['nodata_value']



            # Set SRID

            self.srs = ds_input.get('srid')
@@ -273,15 +273,9 @@ class GDALRaster(GDALBase): 


        return xmin, ymin, xmax, ymax



    @cached_property

    @property

    def bands(self):

        """

        Returns the bands of this raster as a list of GDALBand instances.

        """

        bands = []

        for idx in range(1, capi.get_ds_raster_count(self._ptr) + 1):

            bands.append(GDALBand(self, idx))

        return bands

        return BandList(self)



    def warp(self, ds_input, resampling='NearestNeighbour', max_error=0.0):

        """

tests/gis_tests/rasterapp/test_rasterfield.py

+5 −0
Original line number Diff line number Diff line
@@ -23,6 +23,11 @@ class RasterFieldTest(TransactionTestCase): 
        r.refresh_from_db()

        self.assertIsNone(r.rast)



    def test_access_band_data_directly_from_queryset(self):

        RasterModel.objects.create(rast=JSON_RASTER)

        qs = RasterModel.objects.all()

        qs[0].rast.bands[0].data()



    def test_model_creation(self):

        """

        Test RasterField through a test model.