id summary reporter owner description type status component version severity resolution keywords cc stage has_patch needs_docs needs_tests needs_better_patch easy ui_ux 29239 GEOSGeometry treats WKB and WKT input differently (former incorrectly) MatBurnham Jani Tiainen "I have imported some data from Trimble's OpenStreetMap dataset into PostGIS using `shp2pgsql`. I tried to load this into a Django model generated using `manage.py inspectdb`. This worked fine for the points and lines tables, but not for polygons as I get an error `GEOS_ERROR: IllegalArgumentException: Points of LinearRing do not form a closed linestring`. As far as I can tell, the data from OSM does not form a closed linestring and should not be interpreted as a LinearRing, rather it should be a MultiPolygon. In trying to debug the issue, I created GEOSGeometry objects manually from the same data. I identified a difference depending on the format presented - hex-encoded WKB fails in the way described; the same shape pre-converted in PostGIS to WKT using `SELECT ST_AsEWKT(...)` works fine. {{{#!python >>> from django.contrib.gis.geos import GEOSGeometry >>> wkb = '01060000C00100000001030000C00100000005000000EF03EB93371B9E3F7477425486A349400000000000000000FFFFFFFFFFFFEFFF00AE64C746209E3FBFA6BD778AA349400000000000000000FFFFFFFFFFFFEFFF1224004922459E3F540A70308AA349400000000000000000FFFFFFFFFFFFEFFF027A861513409E3F9E9ACB0D86A349400000000000000000FFFFFFFFFFFFEFFFEF03EB93371B9E3F7477425486A349400000000000000000FFFFFFFFFFFFEFFF' >>> wkt = 'MULTIPOLYGON(((0.0294007 51.2775369 0 -1.79769313486232e+308,0.02942 51.2776632 0 -1.79769313486232e+308,0.0295606 51.2776547 0 -1.79769313486232e+308,0.0295413 51.2775285 0 -1.79769313486232e+308,0.0294007 51.2775369 0 -1.79769313486232e+308)))' >>> GEOSGeometry(wkb) GEOS_ERROR: IllegalArgumentException: Points of LinearRing do not form a closed linestring Traceback (most recent call last): File """", line 1, in File ""/home/mat/virtualenvs/test/lib/python3.6/site-packages/django/contrib/gis/geos/geometry.py"", line 690, in __init__ g = wkb_r().read(force_bytes(geo_input)) File ""/home/mat/virtualenvs/test/lib/python3.6/site-packages/django/contrib/gis/geos/prototypes/io.py"", line 151, in read return wkb_reader_read_hex(self.ptr, wkb, len(wkb)) File ""/home/mat/virtualenvs/test/lib/python3.6/site-packages/django/contrib/gis/geos/libgeos.py"", line 155, in __call__ return self.func(*args, **kwargs) File ""/home/mat/virtualenvs/test/lib/python3.6/site-packages/django/contrib/gis/geos/prototypes/threadsafe.py"", line 48, in __call__ return self.cfunc(self.thread_context.handle.ptr, *args) File ""/home/mat/virtualenvs/test/lib/python3.6/site-packages/django/contrib/gis/geos/prototypes/errcheck.py"", line 32, in check_geom raise GEOSException('Error encountered checking Geometry returned from GEOS C function ""%s"".' % func.__name__) django.contrib.gis.geos.error.GEOSException: Error encountered checking Geometry returned from GEOS C function ""GEOSWKBReader_readHEX_r"". >>> GEOSGeometry(wkt) }}} The error traces through to the upstream C code, but I'm not sure whether that's the root cause or whether it's in the Python wrapper. osgeo.org are being somewhat difficult about creating an account to report the bug there. I'm using stock Django 2.0.2 on an OSBoxes-derived Ubuntu 17.10 VM with Python 3.6.3. GEOS library version appears to be `3.5.1-CAPI-1.9.1 r4246.`" Bug assigned GIS 2.0 Normal Unreviewed 0 0 0 0 0 0