#22352 closed New feature (wontfix)
GeoQuerySet methods: support lookups on reversed o2o relationships as field_name
Reported by: | pchiquet | Owned by: | anonymous |
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Component: | GIS | Version: | dev |
Severity: | Normal | Keywords: | geodjango, GeoQuerySet |
Cc: | mmitar@…, jernej@… | Triage Stage: | Accepted |
Has patch: | yes | Needs documentation: | no |
Needs tests: | no | Patch needs improvement: | yes |
Easy pickings: | no | UI/UX: | no |
Description
GeoQuerySet methods, for example distance, are performed on a given geographic field of the model.
The geographic field to use can be specified thanks the field_name argument. field_name can be a field directly in the model or a lookup to a related field in another model (such as, 'address__point'
). However lookups with reversed one to one relation are not supported.
For example, with the following model:
class User(Model): pass class UserProfile(NamedModel): user = models.OneToOneField(User) point = models.PointField()
the following spatial operation on User fails:
User.objects.all().distance(Point(1,1), field_name='userlocation__point')
and raises the following exception:
Traceback (most recent call last): (...) File "django/contrib/gis/db/models/query.py", line 104, in distance return self._distance_attribute('distance', geom, **kwargs) File "django/contrib/gis/db/models/query.py", line 593, in _distance_attribute procedure_args, geo_field = self._spatial_setup(func, field_name=kwargs.get('field_name', None)) File "django/contrib/gis/db/models/query.py", line 466, in _spatial_setup raise TypeError('%s output only available on GeometryFields.' % func) TypeError: ST_Distance output only available on GeometryFields.
The lookup is supported only if the foreign key is in the Queryset model. I think it would be nice to support reversed relations too.
Change History (17)
comment:1 by , 11 years ago
Owner: | changed from | to
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Status: | new → assigned |
comment:2 by , 11 years ago
comment:3 by , 10 years ago
Triage Stage: | Unreviewed → Accepted |
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Type: | Bug → New feature |
Hi,
This seems like a sensible feature to have so I'll move the ticket to "accepted".
The next step is to find someone familiar with the GIS codebase to review your patch and move the ticket to "ready for checkin".
Thanks.
comment:4 by , 10 years ago
I think the request should also support reverse OneToMany relationships. This Stackoverflow question is relevant: http://stackoverflow.com/questions/25047964/geodjango-geoqueryset-distance-results-in-st-distance-output-only-available-o
comment:5 by , 10 years ago
Patch needs improvement: | set |
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This will require some changes after the _meta refactor branch is merged. Please send a pull request if you can update your patch after that.
comment:6 by , 10 years ago
Cc: | added |
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comment:7 by , 10 years ago
Cc: | added |
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follow-up: 16 comment:9 by , 10 years ago
Resolution: | → wontfix |
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Status: | assigned → closed |
I have tested this with my branch which replaces GeoQuerySet
methods by model functions (#24214). And this was not a problem at all, be it with OneToOne or with OneToMany relations. The syntax will be User.objects.all().annotate(dist=distance('userlocation__point', Point(1,1)))
I'll close this one as won't fix, as I think it is not worth working on to-be-deprecated code. The aforementioned branch is waiting for someone knowledgeable with Oracle GIS to write the Oracle support.
comment:10 by , 10 years ago
The model functions are to be introduced in Django 1.9, and the to-be-deprecated code is still present in Django 1.8 (with LTS). I'm convinced a wontfix is not a good move here.
comment:11 by , 10 years ago
Sorry, but unless this is a regression, it has no chance to enter Django 1.8.
comment:12 by , 10 years ago
Also note that if you really need this functionality, it might be possible to adapt [d9ff5ef36d3f714736d633435d45f03eac9c17b5] to make it a third-party app usable from Django 1.8.
comment:13 by , 10 years ago
This may not be a regression, but I'm sure it's a bug. The field_name
exposes the possibility to span across relationships. It works with ForeignKey
s, but not with OneToOneField
s, which does not make much sense. (The bug occurs because of the way the "field__field__etc"
relationship span is processed).
If a fix won't make it to Django 1.8, I'm going to backport the lookup functions to a third party app as suggested.
comment:14 by , 10 years ago
If it's not a regression from a previous release or a major bug in a new feature it won't be backported. See our supported versions policy.
comment:15 by , 9 years ago
I see this is marked as wontfix, but there seems to be no intermediate solution. Do OneToOne relationships simply not work with GIS in Django?
comment:16 by , 9 years ago
Replying to claudep:
I have tested this with my branch which replaces
GeoQuerySet
methods by model functions (#24214). And this was not a problem at all, be it with OneToOne or with OneToMany relations. The syntax will beUser.objects.all().annotate(dist=distance('userlocation__point', Point(1,1)))
I'll close this one as won't fix, as I think it is not worth working on to-be-deprecated code. The aforementioned branch is waiting for someone knowledgeable with Oracle GIS to write the Oracle support.
So what do we about this in Django 1.8?
Proposed patch: https://github.com/pchiquet/django/commit/d583c5bdd2317a9e1921c80d475f13eba8cb7f71
The git branch: https://github.com/pchiquet/django/tree/ticket_22352