author | Sverre Rabbelier <srabbelier@gmail.com> |
Tue, 02 Dec 2008 22:04:15 +0000 | |
changeset 652 | 02323664d532 |
parent 54 | 03e267d67478 |
permissions | -rw-r--r-- |
54
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Major reorganization of the soc svn repo, to merge into a single App Engine
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""" |
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This module collects helper functions and classes that "span" multiple levels |
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of MVC. In other words, these functions/classes introduce controlled coupling |
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for convenience's sake. |
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""" |
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|
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from django.template import loader |
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from django.http import HttpResponse, Http404 |
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from django.db.models.manager import Manager |
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from django.db.models.query import QuerySet |
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|
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def render_to_response(*args, **kwargs): |
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""" |
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Returns a HttpResponse whose content is filled with the result of calling |
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django.template.loader.render_to_string() with the passed arguments. |
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""" |
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httpresponse_kwargs = {'mimetype': kwargs.pop('mimetype', None)} |
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return HttpResponse(loader.render_to_string(*args, **kwargs), **httpresponse_kwargs) |
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|
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def _get_queryset(klass): |
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""" |
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Returns a QuerySet from a Model, Manager, or QuerySet. Created to make |
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get_object_or_404 and get_list_or_404 more DRY. |
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""" |
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if isinstance(klass, QuerySet): |
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return klass |
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elif isinstance(klass, Manager): |
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manager = klass |
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else: |
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manager = klass._default_manager |
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return manager.all() |
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|
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def get_object_or_404(klass, *args, **kwargs): |
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""" |
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Uses get() to return an object, or raises a Http404 exception if the object |
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does not exist. |
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|
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klass may be a Model, Manager, or QuerySet object. All other passed |
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arguments and keyword arguments are used in the get() query. |
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Note: Like with get(), an MultipleObjectsReturned will be raised if more than one |
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object is found. |
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Todd Larsen <tlarsen@google.com>
parents:
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""" |
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Todd Larsen <tlarsen@google.com>
parents:
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queryset = _get_queryset(klass) |
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try: |
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return queryset.get(*args, **kwargs) |
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except queryset.model.DoesNotExist: |
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raise Http404('No %s matches the given query.' % queryset.model._meta.object_name) |
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|
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def get_list_or_404(klass, *args, **kwargs): |
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""" |
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Uses filter() to return a list of objects, or raise a Http404 exception if |
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the list is empty. |
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|
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klass may be a Model, Manager, or QuerySet object. All other passed |
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arguments and keyword arguments are used in the filter() query. |
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""" |
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queryset = _get_queryset(klass) |
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obj_list = list(queryset.filter(*args, **kwargs)) |
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if not obj_list: |
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raise Http404('No %s matches the given query.' % queryset.model._meta.object_name) |
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return obj_list |