对于使用haystack / solr进行空间搜索，我是否必须同时导入django.contrib.gis.geos.Point和haystack.utils.geo.Point？

Question

I have used haystack 2.1.0 and solr for searching restaurants by name and it works. Now try to add spatial search.

Have followed the instruction on https://django-haystack.readthedocs.org/en/latest/spatial.html . The following statement on that page, "Haystack prefers to work with Point objects, which are located in django.contrib.gis.geos.Point but conviently importable out of haystack.utils.geo.Point." gives me the impression that it is OK to just import haystack.utils.geo.Point. However that doesn't work for me.

Below are the codes I thought are relevant to this question:

Model.py

from haystack.utils.geo import Point

class Restaurant(models.Model):
    name = models.CharField(max_length=250)
    latitude = models.FloatField()
    longitude = models.FloatField()

    def get_location(self):
        return Point(self.longitude, self.latitude)

search_indexes.py

class RestaurantIndex(indexes.SearchIndex, indexes.Indexable):
    name = indexes.CharField(model_attr='name', faceted=True)
    location = indexes.LocationField(model_attr='get_location')

schema.xml

<fieldType name='location' class='solr.LatLonType' subFieldSuffix='_coordinate' />

<field name="name" type="text" indexed="true" stored="true" multiValued="false" />
<field name="name_exact" type="string" indexed="true" stored="true" multiValued="false" />     
<field name="location" type="location" indexed="true" stored="true" multiValued="false" />  

However, when I ran 'python manage.py rebuild_index', I got the following errors:

...
File "...\models.py", line 17, in <module> from haystack.utils.geo import Point
File "...\lib\site-packages\haystack\utils\geo.py", line 2, in <module>
  from django.contrib.gis.geos import Point
File "...\lib\site-packages\django\contrib\gis\geos\__init__.py", line 6, in <module>
  from django.contrib.gis.geos.geometry import GEOSGeometry, wkt_regex, hex_regex
File ...\lib\site-packages\django\contrib\gis\geos\geometry.py", line 16, in <module>
  from django.contrib.gis.geos.coordseq import GEOSCoordSeq
File "...\lib\site-packages\django\contrib\gis\geos\coordseq.py", line 9, in <module>
  from django.contrib.gis.geos.libgeos import CS_PTR
File "...\lib\site-packages\django\contrib\gis\geos\libgeos.py", line 52, in <module>
  '", "'.join(lib_names))
ImportError: Could not find the GEOS library (tried "geos_c", "libgeos_c-1"). Try setting   
GEOS_LIBRARY_PATH in your settings.

This part of the error ' File "...\\lib\\site-packages\\haystack\\utils\\geo.py", line 2, in from django.contrib.gis.geos import Point ' gives me the impression that haystack is calling django.contrib.gis.geos.

Thus my question of whether I need to import both django.contrib.gis.geos.Point and haystack.utils.geo.Point.

I actually installed OSGeo4W64 after seeing this error. However, when I ran 'python manage.py rebuild_index', I got the same error. Then I added "GEOS_LIBRARY_PATH = 'C:/OSGeo4W64/bin'" to setting.py and got the error of "WindowsError: [Error 126] The specified module could not be found".

First, thanks so much for reading my long question. Any help is really appreciated. If I cannot figure this out, my next step is to develop without haystack, which I am not really looking forward to, because I am new to solr.

Again, thanks in advance.

Answer 1

You need to supply the full path to the geos DLL, not the containing directory. Try: GEOS_LIBRARY_PATH = 'C:/OSGeo4W64/bin/geos_c.dll'