Adding scoped sqlalchemy sessions

conda-store-server/conda_store_server/app.py

@@ -107,10 +107,10 @@ def session_factory(self):
 
     @property
     def db(self):
-        if hasattr(self, "_db"):
-            return self._db
-        self._db = self.session_factory()
-        return self._db
+        # we are using a scoped_session which always returns the same
+        # session if within the same thread
+        # https://docs.sqlalchemy.org/en/14/orm/contextual.html
+        return self.session_factory()
 
     @property
     def configuration(self):

conda-store-server/conda_store_server/orm.py

@@ -15,7 +15,7 @@
     UniqueConstraint,
     ForeignKey,
 )
-from sqlalchemy.orm import sessionmaker, relationship
+from sqlalchemy.orm import sessionmaker, relationship, scoped_session
 from sqlalchemy.ext.declarative import declarative_base
 from sqlalchemy import create_engine
 
@@ -296,5 +296,5 @@ def new_session_factory(url="sqlite:///:memory:", reset=False, **kwargs):
 
     Base.metadata.create_all(engine)
 
-    session_factory = sessionmaker(bind=engine)
+    session_factory = scoped_session(sessionmaker(bind=engine))
     return session_factory

conda-store-server/conda_store_server/server/app.py

@@ -85,6 +85,13 @@ def start(self):
         app.conda_store = CondaStore(parent=self, log=self.log)
         app.authentication = self.authentication_class(parent=self, log=self.log)
 
+        @app.after_request
+        def after_request_function(response):
+            # force a new session on next request
+            # since sessions are thread local
+            app.conda_store.session_factory.remove()
+            return response
+
         # add dynamic routes
         for route, method, func in app.authentication.routes:
             app.add_url_rule(route, func.__name__, func, methods=[method])