Baked Query Support

Author: jcroll

README.md

@@ -46,6 +46,16 @@ being cached, try using a deferred query like:
 YourModel.query.options(defer('crazy_column')).options(FromCache(cache)).get()
 ```
 
+You can also integrate with [baked queries](https://docs.sqlalchemy.org/en/13/orm/extensions/baked.html) like so:
+```python
+baked_query = bakery(lambda session: session.query(YourModel))
+baked_query += lambda q: q.filter(YourModel.id == bindparam('id'))
+
+obj = baked_query(YourModel.query.session) \
+.with_post_criteria(lambda q: q.options(FromCache(cache))) \
+.params(id=id).one()
+```
+
 Take a look at [Dogpile Caching example][] to more details about how
 `CachingQuery` works. Most changes to their were made just to integrate it
 with Flask, Flask-SQLAlchemy and Flask-Caching instead of Dogpile.

flask_sqlalchemy_caching/core.py

@@ -51,6 +51,29 @@ def create_func(): return list(BaseQuery.__iter__(self))
         else:
             return BaseQuery.__iter__(self)
 
+    def _execute_and_instances(self, context):
+        """override _execute_and_instances to pull results from dogpile
+                if the query is invoked directly from an external context.
+               This method is necessary in order to maintain compatibility
+               with the "baked query" system now used by default in some
+               relationship loader scenarios.   Note also the
+               RelationshipCache._generate_cache_key method which enables
+               the baked query to be used within lazy loads.
+               .. versionadded:: 1.2.7
+            """
+        super_ = super(CachingQuery, self)
+
+        if context.query is not self and hasattr(self, "_cache"):
+            # special logic called when the Query._execute_and_instances()
+            # method is called directly from the baked query
+            return iter(
+                self.get_value(
+                    createfunc=lambda: list(super_._execute_and_instances(context))
+                )
+            )
+        else:
+            return super_._execute_and_instances(context)
+
     def _get_cache_plus_key(self):
         """Return a cache region plus key."""
         return self._cache.cache, self._get_key()