Haystack - Why does RealtimeSearchIndex sometimes not update my saved object

问题

I'm using Haystack and Whoosh with Django

Within search_index.py I have this

class PageIndex(RealTimeSearchIndex):
    text = CharField(document=True, use_template=True)
    creator = CharField(model_attr='creator')
    created = DateTimeField(model_attr='created')
    org = CharField(model_attr='organisation')

site.register(Page, PageIndex)

My template looks like this

{{ object.name }}
{{ object.description }}
{{ object.template|striptags }}
{% for k,v in object.get_variables.items %}
{{ v }}
{% endfor %}

If I save the Page with an updated name or description then it updates straight away and includes the variables from get_variables.items in the template. However if I update just the variable then it doesn't update.

Is it because variable is another object that's related to it and even though I am saving on the same page it does not pick up a change to the Page? If so how do I force to update the Page item when I'm updating related objects?

回答1:

I concur with Daniel Hepper, but I think the easiest solution here is to attach a listener to your related model's post_save signal (see https://docs.djangoproject.com/en/dev/topics/signals/) and in that, reindex the model.

E.g, in myapp/models.py, given model MyRelatedModel which has a foreignkey to MyModel

from myapp.search_indexes import MyModelIndex

def reindex_mymodel(sender, **kwargs):
    MyModelIndex().update_object(kwargs['instance'].mymodel)
models.signals.post_save.connect(reindex_mymodel, sender=MyRelatedModel)

回答2:

A RealTimeSearchIndex only updates the search index when a model it is registered on is saved or deleted, or to be more precise, when the post_save/post_delete signal of the model is emitted. These signals are not emitted if a related model is deleted/saved or when a bulk update/delete operation is executed.

To solve your problem, you could create a subclass of RealTimeSearchIndex that also updates the index on post_save/post_delete signals of the related model.

回答3:

Just a note for more recent viewers of this post ---- RealTimeSearchIndex has been deprecated.

See here for the Haystack post about it.

回答4:

For recent viewers, here's a solution based on the new RealtimeSignalProcessor:

In myapp/signals.py:

class RelatedRealtimeSignalProcessor(RealtimeSignalProcessor):

    def handle_save(self, sender, instance, **kwargs):
        if hasattr(instance, 'reindex_related'):
            for related in instance.reindex_related:
                related_obj = getattr(instance, related)
                self.handle_save(related_obj.__class__, related_obj)
        return super(RelatedRealtimeSignalProcessor, self).handle_save(sender, instance, **kwargs)

    def handle_delete(self, sender, instance, **kwargs):
        if hasattr(instance, 'reindex_related'):
            for related in instance.reindex_related:
                related_obj = getattr(instance, related)
                self.handle_delete(related_obj.__class__, related_obj)
        return super(RelatedRealtimeSignalProcessor, self).handle_delete(sender, instance, **kwargs)

In settings.py:

HAYSTACK_SIGNAL_PROCESSOR = 'myapp.signals.RelatedRealtimeSignalProcessor'

In models.py:

class Variable(models.Model):
    reindex_related = ('page',)

    page = models.ForeignKey(Page)

Now when a Variable is saved, the index for the related Page will also be updated.

(TODO: This doesn't work for extended relationships like foo__bar, or for many-to-many fields. But it should be straightforward to extend it to handle those if you need to.)

来源：https://stackoverflow.com/questions/7041657/haystack-why-does-realtimesearchindex-sometimes-not-update-my-saved-object

标签

django-haystack