Django通用UpdateView：获取要更新的对象

Question

I'm actually using the django.views.generic.edit.UpdateView to update a models specific fields. Since I'm not passing the primary key or slug of the object to be updated, I'm simply overriding the get_object method:

def get_object(self, queryset=None):
    return Model.objects.get(user__id=self.request.user.id)

If there is no object found at get_object I'm receiving a 'Query does not match[...]' error, which is totally fine. But in case of an exception I'd like to redirect the user instead of showing the exception output. Unfortunately the get_object method forbids redirects as django expects it to return an object.

Is there any elegant way to check if the requested object exists and if not to redirect the user? I'd also like to avoid overriding the dispatch method to perform the check for object existence there. This would lead to an further unnecessary database query. So I'd had three queries for a simple update view.

Any advice would be really great :)

Answer 1

You could do the get in your get_object method, allow a DoesNotExist error to propagate (don't catch it), and override the dispatch method and catch the DoesNotExist exception there. From dispatch, you can return a redirect.

Something like:

def dispatch(...):
    try:
         return super(...)  # call superclass dispatch
    except Model.DoesNotExist:
         return ... your redirection ...