[Django] #31450: Querying on ArrayField(PointField) returns string instead of list
Django
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Reporter: nsangwan | Owner: (none)
Type: Bug | Status: new
Component: | Version: 3.0
contrib.postgres | Keywords: ArrayField,
Severity: Normal | PointField
Triage Stage: | Has patch: 0
Unreviewed |
Needs documentation: 0 | Needs tests: 0
Patch needs improvement: 0 | Easy pickings: 0
UI/UX: 0 |
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The following code
{{{
from django.db import models
from django.contrib.postgres.fields import ArrayField
from django.contrib.gis.db.models import PointField
class Foo(models.Model):
bar = ArrayField(models.TextField)
baz = ArrayField(PointField())
}}}
has this wrong behaviour:
{{{
x = Foo.objects.get(id=1)
x.bar # => ['Foo', 'Bar']
x.baz # => '{HexRepresentationofPoint1,HexRepresentationofPoint2}'
}}}
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Ticket URL: <https://code.djangoproject.com/ticket/31450>
Django <https://code.djangoproject.com/>
The Web framework for perfectionists with deadlines.
Django
-------------------------------------+-------------------------------------
Type: Bug | Status: new
Component: contrib.postgres | Version: 3.0
Severity: Normal | Resolution:
Keywords: ArrayField, | Triage Stage:
PointField | Unreviewed
Has patch: 0 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
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* Attachment "postgis_tests.zip" added.
Reproduce test case for #31450
Django
-------------------------------------+-------------------------------------
Type: Bug | Status: new
Component: contrib.postgres | Version: 3.0
Severity: Normal | Resolution:
PointField |
Has patch: 0 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
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* stage: Unreviewed => Accepted
Comment:
Thanks for the report. Reproduced at
578c03b276e435bcd3ce9eb17b81e85135c2d3f3 with the attached test case.
--
Ticket URL: <https://code.djangoproject.com/ticket/31450#comment:1>
Django
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| Ramezani
Type: Bug | Status: assigned
Component: contrib.postgres | Version: 3.0
Severity: Normal | Resolution:
Keywords: ArrayField, | Triage Stage: Accepted
PointField |
Needs tests: 0 | Patch needs improvement: 1
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
* owner: (none) => Hasan Ramezani
* needs_better_patch: 0 => 1
* has_patch: 0 => 1
* status: new => assigned
Comment:
[https://github.com/django/django/pull/12732 PR]
--
Ticket URL: <https://code.djangoproject.com/ticket/31450#comment:2>
Django
-------------------------------------+-------------------------------------
| Ramezani
Type: Bug | Status: assigned
Component: contrib.postgres | Version: 3.0
Severity: Normal | Resolution:
Keywords: ArrayField, | Triage Stage: Accepted
PointField |
Needs tests: 0 | Patch needs improvement: 1
Easy pickings: 0 | UI/UX: 0
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Comment (by Hasan Ramezani):
Comment from the PR:
Thanks @Simon for your suggestion.
I've tried to create and register a new array type for `geometry` based on
your suggestion at #8453. here is the code:
{{{
def get_geometry_oids(connection_alias):
with connections[connection_alias].cursor() as cursor:
cursor.execute("SELECT typarray FROM pg_type WHERE typname =
'geometry'")
return tuple(row[0] for row in cursor)
...
geometry_oids = get_geometry_oids(connection.alias)
new_type = psycopg2.extensions.new_type(geometry_oids, "geometry",
caster) # caster is function to cast hex to geometry object
array_type = psycopg2.extensions.new_array_type(geometry_oids,
'geometry[]', new_type)
psycopg2.extensions.register_type(array_type, None)
}}}
The problem is that in `caster` function, I get all items in array not one
item. something like this:
`0101000020E610000000000000000018400000000000003840:0101000020E610000000000000000014400000000000003740`
which is represent two points that seprated by `:`.
I've checed the column value in postgres console. for an array of points I
got this:
`{0101000020E6100000000000000000F03F0000000000000040:0101000020E6100000000000000000F03F0000000000000040}`
While, I got below value for an array of chars:
`{foo,bar}`
the difference between two cases is for an array of points I got `:` as a
separator, but for an array of chars I got `,`.
I also tried to insert data from console to an array of points column by:
`insert into test values (ARRAY[st_geomFromText('POINT(1 1)', 4326),
st_geomFromText('POINT(1 1)', 4326)]);`
the result was the same(`:` as separator).
Do you have any idea?
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Ticket URL: <https://code.djangoproject.com/ticket/31450#comment:3>
Django
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| Ramezani
Type: Bug | Status: assigned
Component: contrib.postgres | Version: 3.0
Severity: Normal | Resolution:
Keywords: ArrayField, | Triage Stage: Accepted
PointField |
Needs tests: 0 | Patch needs improvement: 1
Easy pickings: 0 | UI/UX: 0
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* cc: Simon Charette (added)
--
Ticket URL: <https://code.djangoproject.com/ticket/31450#comment:4>
Django
-------------------------------------+-------------------------------------
| Ramezani
Type: Bug | Status: assigned
Component: contrib.postgres | Version: 3.0
Severity: Normal | Resolution:
Keywords: ArrayField, | Triage Stage: Accepted
PointField |
Needs tests: 0 | Patch needs improvement: 1
Easy pickings: 0 | UI/UX: 0
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Comment (by Simon Charette):
I spent a few hours trying to figure it out but it looks like there might
be something wrong with `psycopg2`. When registering an array type for
`geometry` from the retrieved oid it simply doesn't get invoked for
columns of type `geometry(POINT, srid)[]` behind
`ArrayField(PointField())`.
Hasan your code is registering an array type and a scalar type for the
same `oid`, you want to register a type for the scalar oid and an array
type for array oid. Look at how `get_hstore_oids` and
`psycopg2.extras.register_hstore` do it.
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Ticket URL: <https://code.djangoproject.com/ticket/31450#comment:5>
Django
-------------------------------------+-------------------------------------
Type: Bug | Status: new
Component: contrib.postgres | Version: 3.0
Severity: Normal | Resolution:
Keywords: ArrayField, | Triage Stage: Accepted
PointField |
Needs tests: 0 | Patch needs improvement: 1
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
* owner: Hasan Ramezani => (none)
* status: assigned => new
--
Ticket URL: <https://code.djangoproject.com/ticket/31450#comment:6>
Django
-------------------------------------+-------------------------------------
Type: Bug | Status: assigned
Severity: Normal | Resolution:
Keywords: ArrayField, | Triage Stage: Accepted
PointField |
Needs tests: 0 | Patch needs improvement: 1
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* owner: (none) => Saurabh
Ticket URL: <https://code.djangoproject.com/ticket/31450#comment:7>