[Django] #30020: Support reading null values for numeric fields on Shapefile import via LayerMapping
Django
LayerMapping
-------------------------------------+-------------------------------------
Reporter: Kathryn | Owner: nobody
Killebrew |
Type: New | Status: new
feature |
Component: GIS | Version:
Severity: Normal | Keywords: GIS, GEOS,
Triage Stage: | LayerMapping
Unreviewed | Has patch: 0
Needs documentation: 0 | Needs tests: 0
Patch needs improvement: 0 | Easy pickings: 0
UI/UX: 0 |
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On reading a Shapefile into a model object via `LayerMapping`, set numeric
field value to `None` instead of zero if the model field is nullable and
input field value is either null or unset. Currently, both nulls and
zeroes in the input are stored as zeroes.
Shapefiles do not officially support storing nulls:
http://resources.esri.com/help/9.3/ArcGISDesktop/com/Gp_ToolRef/geoprocessing_tool_reference/geoprocessing_considerations_for_shapefile_output.htm
However, on inspecting the DBF contents via `ogrinfo` with GDAL 2.1 or
2.2, both zeroes and nulls display, so some unofficial support exists.
GDAL 2.2 added support for distinguishing between "unset" fields and those
explicitly set to null:
https://trac.osgeo.org/gdal/wiki/rfc67_nullfieldvalues
Adding null support should be possible by either checking before casting
the value with OGR `IsFieldSetAndNotNull` on GDAL 2.2+ or checking with
OGR `IsFieldSet` on older GDAL versions:
https://www.gdal.org/classOGRFeature.html#a260b925400b72914eb1b8cc9a3bf4029
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Ticket URL: <https://code.djangoproject.com/ticket/30020>
Django <https://code.djangoproject.com/>
The Web framework for perfectionists with deadlines.
Django
LayerMapping
-------------------------------------+-------------------------------------
Type: New feature | Status: new
Component: GIS | Version:
Severity: Normal | Resolution:
Keywords: GIS, GEOS, | Triage Stage: Accepted
LayerMapping |
Has patch: 0 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
* stage: Unreviewed => Accepted
--
Ticket URL: <https://code.djangoproject.com/ticket/30020#comment:1>
Django
LayerMapping
-------------------------------------+-------------------------------------
| Killebrew
Type: New feature | Status: assigned
Component: GIS | Version:
Severity: Normal | Resolution:
Keywords: GIS, GEOS, | Triage Stage: Accepted
LayerMapping |
Has patch: 0 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
* owner: nobody => Kathryn Killebrew
* status: new => assigned
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Ticket URL: <https://code.djangoproject.com/ticket/30020#comment:2>
Django
LayerMapping
-------------------------------------+-------------------------------------
| Killebrew
Type: New feature | Status: assigned
Severity: Normal | Resolution:
Keywords: GIS, GEOS, | Triage Stage: Accepted
LayerMapping |
Has patch: 0 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
* cc: claude@… (added)
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Ticket URL: <https://code.djangoproject.com/ticket/30020#comment:3>
Django
LayerMapping
-------------------------------------+-------------------------------------
| Killebrew
Type: New feature | Status: assigned
Severity: Normal | Resolution:
Keywords: GIS, GEOS, | Triage Stage: Accepted
LayerMapping |
Has patch: 1 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
* has_patch: 0 => 1
Comment:
[https://github.com/django/django/pull/10760 PR]
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Ticket URL: <https://code.djangoproject.com/ticket/30020#comment:4>
Django
LayerMapping
-------------------------------------+-------------------------------------
| Killebrew
Type: New feature | Status: assigned
Severity: Normal | Resolution:
Keywords: GIS, GEOS, | Triage Stage: Ready for
LayerMapping | checkin
Has patch: 1 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
* stage: Accepted => Ready for checkin
--
Ticket URL: <https://code.djangoproject.com/ticket/30020#comment:5>
Django
LayerMapping
-------------------------------------+-------------------------------------
| Killebrew
Component: GIS | Version:
Severity: Normal | Resolution: fixed
Keywords: GIS, GEOS, | Triage Stage: Ready for
LayerMapping | checkin
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
* status: assigned => closed
* resolution: => fixed
Comment:
In [changeset:"75d627888bf42f8de6064a0bd665c98c0df66c55" 75d6278]:
{{{
#!CommitTicketReference repository=""
revision="75d627888bf42f8de6064a0bd665c98c0df66c55"
Fixed #30020 -- Fixed reading nulls with LayerMapping.
}}}
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Ticket URL: <https://code.djangoproject.com/ticket/30020#comment:6>