mirror of https://github.com/django/django.git
96 lines
2.5 KiB
Plaintext
96 lines
2.5 KiB
Plaintext
================
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Geographic Feeds
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================
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.. module:: django.contrib.gis.feeds
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:synopsis: GeoDjango's framework for generating spatial feeds.
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GeoDjango has its own :class:`Feed` subclass that may embed location information
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in RSS/Atom feeds formatted according to either the `Simple GeoRSS`__ or
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`W3C Geo`_ standards. Because GeoDjango's syndication API is a superset of
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Django's, please consult :doc:`Django's syndication documentation
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</ref/contrib/syndication>` for details on general usage.
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.. _W3C Geo: http://www.w3.org/2003/01/geo/
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__ http://georss.org/1.0#simple
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Example
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=======
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API Reference
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=============
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``Feed`` Subclass
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-----------------
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.. class:: Feed
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In addition to methods provided by
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the :class:`django.contrib.syndication.views.Feed`
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base class, GeoDjango's ``Feed`` class provides
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the following overrides. Note that these overrides may be done in multiple ways::
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from django.contrib.gis.feeds import Feed
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class MyFeed(Feed):
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# First, as a class attribute.
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geometry = ...
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item_geometry = ...
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# Also a function with no arguments
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def geometry(self):
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...
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def item_geometry(self):
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...
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# And as a function with a single argument
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def geometry(self, obj):
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...
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def item_geometry(self, item):
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...
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.. method:: geometry(obj)
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Takes the object returned by ``get_object()`` and returns the *feed's*
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geometry. Typically this is a ``GEOSGeometry`` instance, or can be a
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tuple to represent a point or a box. For example::
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class ZipcodeFeed(Feed):
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def geometry(self, obj):
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# Can also return: `obj.poly`, and `obj.poly.centroid`.
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return obj.poly.extent # tuple like: (X0, Y0, X1, Y1).
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.. method:: item_geometry(item)
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Set this to return the geometry for each *item* in the feed. This
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can be a ``GEOSGeometry`` instance, or a tuple that represents a
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point coordinate or bounding box. For example::
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class ZipcodeFeed(Feed):
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def item_geometry(self, obj):
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# Returns the polygon.
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return obj.poly
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``SyndicationFeed`` Subclasses
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------------------------------
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The following :class:`django.utils.feedgenerator.SyndicationFeed` subclasses
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are available:
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.. class:: GeoRSSFeed
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.. class:: GeoAtom1Feed
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.. class:: W3CGeoFeed
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.. note::
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`W3C Geo`_ formatted feeds only support
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:class:`~django.contrib.gis.db.models.PointField` geometries.
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