Improve db Session logic

solvable/src/webservice/model.py

@@ -14,16 +14,17 @@ session_factory = sessionmaker(
 
 
 @contextmanager
-def Session():
-    session = session_factory()
+def Session(factory=session_factory):
+    session = factory()
     try:
         yield session
         session.commit()
     except:
         session.rollback()
         raise
-    finally:
-        session.close()
+    # session is closed by flask
+    # finally:
+    #     session.close()
 
 
 Base = declarative_base()

solvable/src/webservice/server.py

@@ -1,8 +1,9 @@
 from os import urandom, getenv
+from functools import partial
 
 from flask import Flask, render_template, request, session, url_for, g
 
-from model import init_db, session_factory
+from model import init_db, session_factory, Session
 from user_ops import UserOps
 from errors import InvalidCredentialsError, UserExistsError
 
@@ -20,6 +21,8 @@ def get_db_session():
         g.db_session = session_factory()
     return g.db_session
 
+Session = partial(Session, get_db_session)
+
 
 @app.teardown_appcontext
 def close_db_session(err): # pylint: disable=unused-argument
@@ -31,9 +34,12 @@ def close_db_session(err): # pylint: disable=unused-argument
 def index():
     if request.method == 'POST':
         try:
-            UserOps(request.form.get('username'),
+            with Session() as db_session:
+                UserOps(
+                    request.form.get('username'),
                     request.form.get('password'),
-                    get_db_session()).authenticate()
+                    db_session
+                ).authenticate()
         except InvalidCredentialsError:
             return render_template('login.html', alert='Invalid credentials!')
 
@@ -61,11 +67,12 @@ def register():
             return render_template('register.html', alert='Passwords do not match! Please try again.')
 
         try:
-            UserOps(
-                request.form.get('username'),
-                request.form.get('password'),
-                get_db_session()
-            ).register()
+            with Session() as db_session:
+                UserOps(
+                    request.form.get('username'),
+                    request.form.get('password'),
+                    db_session
+                ).register()
         except UserExistsError:
             return render_template('register.html', alert='Username already in use.')
 

solvable/src/webservice/user_ops.py

@@ -62,6 +62,5 @@ class UserOps:
             passwordhash=PasswordHasher.hash(self.password)
         )
         self.db_session.add(user)
-        self.db_session.commit()
 
         self.log(f'User "{self.username}" registered!')