Filter exact through tags
pancakeDevelopment opened this issue · 6 comments
pancakeDevelopment commented
I'm trying to do this:
_q = ["tag1","tag2]
Message.objects.filter(Q(tags__name__in=_q)).distinct().order_by('timestamp')
Now I want a result, where every message has exact those two tags - not just one of them. I've tried it with __name__exact=_q, but it isn't working. Any ideas how to solve this issue?
rtpg commented
I haven't tried this but I believe that doing Message.objects.filter(tags__name="tag1").filter(tags__name="tag2") should give you what you want.
That should return your messages that include tag1.... that are then filtered down by messages including tag2 (so the end result has those including both).
If you want to find those with exactly those two tags (i.e. no other tags), then you will want to filter those down, then there's a bit more work involved.
has_both_tags = Message.objects.filter(tags__name="tag1").filter(tags__name="tag2")
# get all the tag objects that you are not interested in (using the through model)
all_other_tags = Message.tags.through.objects.exclude(name__in=["tag1", "tag2")
# filter out messages that have any of those other tags
only_both_tags = has_both_tags.exclude(tags__in=all_other_tags)
I haven't tested this but the through model should be helpful for you. Core idea, mathematically is:
- get the set of messages with both tags
- get all the tags that you do not care about
- get the set of messages with any tags you don't care about
- exclude that latter set from this set
developcreativo commented
- btenga el conjunto de mensajes con cual
feed = Feed.hashtags.through.objects.filter(tag__name__in=["demo"])
`
class TaggitManager:
hashtags = TaggableManager(through=UUIDTaggedItem)
class Meta:
abstract = True
class UUIDTaggedItem(GenericUUIDTaggedItemBase, TaggedItemBase):
pass
class Feed(UUIDModel, TimeStampedModel, mongo_models.Model, TaggitManager):
#more field`
Internal Server Error: /api/v1/feed/feed-hashtag-list/
Traceback (most recent call last):
File "/usr/local/lib/python3.10/dist-packages/django/db/backends/utils.py", line 89, in _execute
return self.cursor.execute(sql, params)
psycopg2.errors.UndefinedTable: relation "feed_feed" does not exist
LINE 1: ...is_announcement", "feed_feed"."count_shared" FROM "feed_feed...
^
The above exception was the direct cause of the following exception:
Traceback (most recent call last):
File "/usr/local/lib/python3.10/dist-packages/asgiref/sync.py", line 486, in thread_handler
raise exc_info[1]
File "/usr/local/lib/python3.10/dist-packages/django/core/handlers/exception.py", line 42, in inner
response = await get_response(request)
File "/usr/local/lib/python3.10/dist-packages/django/core/handlers/base.py", line 253, in _get_response_async
response = await wrapped_callback(
File "/usr/local/lib/python3.10/dist-packages/asgiref/sync.py", line 448, in __call__
ret = await asyncio.wait_for(future, timeout=None)
File "/usr/lib/python3.10/asyncio/tasks.py", line 408, in wait_for
return await fut
File "/usr/local/lib/python3.10/dist-packages/asgiref/current_thread_executor.py", line 22, in run
result = self.fn(*self.args, **self.kwargs)
File "/usr/local/lib/python3.10/dist-packages/asgiref/sync.py", line 490, in thread_handler
return func(*args, **kwargs)
File "/usr/lib/python3.10/contextlib.py", line 79, in inner
return func(*args, **kwds)
File "/usr/lib/python3.10/contextlib.py", line 79, in inner
return func(*args, **kwds)
File "/usr/local/lib/python3.10/dist-packages/django/views/decorators/csrf.py", line 54, in wrapped_view
return view_func(*args, **kwargs)
File "/usr/local/lib/python3.10/dist-packages/rest_framework/viewsets.py", line 125, in view
return self.dispatch(request, *args, **kwargs)
File "/usr/local/lib/python3.10/dist-packages/rest_framework/views.py", line 509, in dispatch
response = self.handle_exception(exc)
File "/usr/local/lib/python3.10/dist-packages/rest_framework/views.py", line 469, in handle_exception
self.raise_uncaught_exception(exc)
File "/usr/local/lib/python3.10/dist-packages/rest_framework/views.py", line 480, in raise_uncaught_exception
raise exc
File "/usr/local/lib/python3.10/dist-packages/rest_framework/views.py", line 506, in dispatch
response = handler(request, *args, **kwargs)
File "/var/www/sportyeah/apps/feed/api/v1/views/feed.py", line 351, in feed_hashtag_list
return super().list(request, *args, **kwargs)
File "/usr/local/lib/python3.10/dist-packages/rest_framework/mixins.py", line 38, in list
queryset = self.filter_queryset(self.get_queryset())
File "/var/www/sportyeah/apps/feed/api/v1/views/feed.py", line 198, in get_queryset
print(feed)
File "/usr/local/lib/python3.10/dist-packages/django/db/models/query.py", line 373, in __repr__
return "<%s %r>" % (self.__class__.__name__, data)
File "/usr/local/lib/python3.10/dist-packages/django/db/models/base.py", line 606, in __repr__
return "<%s: %s>" % (self.__class__.__name__, self)
File "/usr/local/lib/python3.10/dist-packages/taggit/models.py", line 97, in __str__
"object": self.content_object,
File "/usr/local/lib/python3.10/dist-packages/django/contrib/contenttypes/fields.py", line 250, in __get__
rel_obj = ct.get_object_for_this_type(pk=pk_val)
File "/usr/local/lib/python3.10/dist-packages/django/contrib/contenttypes/models.py", line 179, in get_object_for_this_type
return self.model_class()._base_manager.using(self._state.db).get(**kwargs)
File "/usr/local/lib/python3.10/dist-packages/django/db/models/query.py", line 646, in get
num = len(clone)
File "/usr/local/lib/python3.10/dist-packages/django/db/models/query.py", line 376, in __len__
self._fetch_all()
File "/usr/local/lib/python3.10/dist-packages/django/db/models/query.py", line 1866, in _fetch_all
self._result_cache = list(self._iterable_class(self))
File "/usr/local/lib/python3.10/dist-packages/django/db/models/query.py", line 87, in __iter__
results = compiler.execute_sql(
File "/usr/local/lib/python3.10/dist-packages/django/db/models/sql/compiler.py", line 1395, in execute_sql
cursor.execute(sql, params)
File "/usr/local/lib/python3.10/dist-packages/django/db/backends/utils.py", line 103, in execute
return super().execute(sql, params)
File "/usr/local/lib/python3.10/dist-packages/django/db/backends/utils.py", line 67, in execute
return self._execute_with_wrappers(
File "/usr/local/lib/python3.10/dist-packages/django/db/backends/utils.py", line 80, in _execute_with_wrappers
return executor(sql, params, many, context)
File "/usr/local/lib/python3.10/dist-packages/django/db/backends/utils.py", line 84, in _execute
with self.db.wrap_database_errors:
File "/usr/local/lib/python3.10/dist-packages/django/db/utils.py", line 91, in __exit__
raise dj_exc_value.with_traceback(traceback) from exc_value
File "/usr/local/lib/python3.10/dist-packages/django/db/backends/utils.py", line 89, in _execute
return self.cursor.execute(sql, params)
django.db.utils.ProgrammingError: relation "feed_feed" does not exist
LINE 1: ...is_announcement", "feed_feed"."count_shared" FROM "feed_feed...
developcreativo commented
feed = Feed.objects.filter(tags__name="demo")
django.core.exceptions.FieldError: Cannot resolve keyword 'tags' into field
or
feed = Feed.objects.filter(hashtags__name="demo")
django.core.exceptions.FieldError: Cannot resolve keyword 'hashtags' into field
developcreativo commented
@rtpg Any way to tell my model to filter me by hashtags since none of the ways I have tried has been satisfactory.
ethagnawl commented
@rtpg I can confirm that your chained filter example works as expected. Thank you for that!
I'm curious to know if you have a suggested way of building up a dynamic filter chain, though. I'm trying to compose a list of Q filters combined with the & operator and it's not working. What's really interesting is that using & to compose filter chains does work.
# works
xs = Band.objects.filter(
custom_tags__name='punk'
) & Band.objects.filter(
custom_tags__name='indie'
)
# does not work
xxs = Band.objects.filter(
Q(custom_tags__name='punk') &
Q(custom_tags__name='indie')
)