diff options
| -rw-r--r-- | mediagoblin/db/models.py | 55 |
1 files changed, 41 insertions, 14 deletions
diff --git a/mediagoblin/db/models.py b/mediagoblin/db/models.py index a771ec2f..9829ff9d 100644 --- a/mediagoblin/db/models.py +++ b/mediagoblin/db/models.py @@ -95,11 +95,17 @@ class GenericModelReference(Base): # Ensure that everything has it's ID set obj.save(commit=False) - self.obj_pk = obj.id + self.obj_pk = getattr(obj, pk_column) self.model_type = obj.__tablename__ def _get_model_from_type(self, model_type): - """ Gets a model from a tablename (model type) """ + """ + Gets a model from a tablename (model type) + + This currently only works for core models, I've not been able to find + this data built by SQLAlchemy, the closes I found was + Base._metadata.tables but that only gives me a `Table` object. + """ if getattr(self.__class__, "_TYPE_MAP", None) is None: # We want to build on the class (not the instance) a map of all the # models by the table name (type) for easy lookup, this is done on @@ -111,8 +117,28 @@ class GenericModelReference(Base): return self.__class__._TYPE_MAP[model_type] + @classmethod + def find_for_obj(cls, obj): + """ Finds a GMR for an object or returns None """ + # Is there one for this already. + model = type(obj) + pk = getattr(obj, "id") + + gmr = GenericModelReference.query.filter_by( + obj_pk=pk, + model_type=model.__tablename__ + ) + + return gmr.first() + class GenericForeignKey(types.TypeDecorator): + """ + GenericForeignKey type used to refer to objects with an integer foreign key. + + This will break referential integrity, only use in places where that is + not important. + """ impl = Integer @@ -133,21 +159,23 @@ class GenericForeignKey(types.TypeDecorator): return gmr.get_object() def process_bind_param(self, value, *args, **kwargs): - """ Save the foreign key """ + """ + Save the foreign key + + There is no mechanism to put a constraint to make this only save foreign + keys to GenericModelReference. The only thing you can do is have this + method which only saves GenericModelReference. + """ if value is None: return None - # Is there one for this already. - model = type(value) - pk = getattr(value, "id") + # Find the GMR if there is one. + gmr = GenericModelReference.find_for_obj(value) - gmr = GenericModelReference.query.filter_by(id=pk).first() + # Create one if there isn't if gmr is None: - # We need to create one - gmr = GenericModelReference( - obj_pk=pk, - model_type=model.__tablename__ - ) + gmr = GenericModelReference() + gmr.set_object(value) gmr.save() return gmr.id @@ -1429,8 +1457,7 @@ MODELS = [ CommentSubscription, ReportBase, CommentReport, MediaReport, UserBan, Privilege, PrivilegeUserAssociation, RequestToken, AccessToken, NonceTimestamp, - Activity, ActivityIntermediator, Generator, - Location, GenericModelReference] + Activity, Generator, Location, GenericModelReference] """ Foundations are the default rows that are created immediately after the tables |