Commit 888c9b64 authored by Marten Kenbeek's avatar Marten Kenbeek Committed by Markus Holtermann
Browse files

Fixed #24397 -- Sped up rendering multiple model states. 

Set apps.ready to False when rendering multiple models. This prevents
that the cache on Model._meta is expired on all models after each time a
single model is rendered. Prevented that Apps.clear_cache() refills the
cache on Apps.get_models(), so that the wrong value cannot be cached
when cloning a StateApps.
parent 180f75c2

django/apps/registry.py

+5 −2
Original line number Diff line number Diff line
@@ -326,7 +326,10 @@ class Apps(object): 
        # the relation tree and the fields cache.

        self.get_models.cache_clear()

        if self.ready:

            for model in self.get_models(include_auto_created=True):

            # Circumvent self.get_models() to prevent that the cache is refilled.

            # This particularly prevents that an empty value is cached while cloning.

            for app_config in self.app_configs.values():

                for model in app_config.get_models(include_auto_created=True):

                    model._meta._expire_cache()

django/db/migrations/state.py

+7 −0
Original line number Diff line number Diff line
@@ -236,6 +236,10 @@ class StateApps(Apps): 
        # base errors, until the size of the unrendered models doesn't

        # decrease by at least one, meaning there's a base dependency loop/

        # missing base.

        if not model_states:

            return

        # Prevent that all model caches are expired for each render.

        self.ready = False

        unrendered_models = model_states

        while unrendered_models:

            new_unrendered_models = []
@@ -245,6 +249,7 @@ class StateApps(Apps): 
                except InvalidBasesError:

                    new_unrendered_models.append(model)

            if len(new_unrendered_models) == len(unrendered_models):

                self.ready = True

                raise InvalidBasesError(

                    "Cannot resolve bases for %r\nThis can happen if you are inheriting models from an "

                    "app with migrations (e.g. contrib.auth)\n in an app with no migrations; see "
@@ -252,6 +257,8 @@ class StateApps(Apps): 
                    "for more" % (new_unrendered_models, get_docs_version())

                )

            unrendered_models = new_unrendered_models

        self.ready = True

        self.clear_cache()



    def clone(self):

        """