Replace assert with proper check & add tests (#235)

Author: panagiks

aiohttp_session/__init__.py

@@ -114,7 +114,8 @@ async def get_session(request):
 
 def session_middleware(storage):
 
-    assert isinstance(storage, AbstractStorage), storage
+    if not isinstance(storage, AbstractStorage):
+        raise RuntimeError("Expected AbstractStorage got {}".format(storage))
 
     @web.middleware
     async def factory(request, handler):

tests/test_abstract_storage.py

@@ -3,8 +3,8 @@
 import time
 
 from aiohttp import web
-from aiohttp_session import (session_middleware,
-                             get_session, SimpleCookieStorage)
+from aiohttp_session import get_session, SimpleCookieStorage
+from aiohttp_session import setup as setup_middleware
 
 
 def make_cookie(client, data):
@@ -18,8 +18,8 @@ def make_cookie(client, data):
 
 
 def create_app(loop, handler):
-    middleware = session_middleware(SimpleCookieStorage(max_age=10))
-    app = web.Application(middlewares=[middleware], loop=loop)
+    app = web.Application(loop=loop)
+    setup_middleware(app, SimpleCookieStorage(max_age=10))
     app.router.add_route('GET', '/', handler)
     return app
 

tests/test_get_session.py

@@ -2,7 +2,7 @@
 
 from aiohttp.test_utils import make_mocked_request
 
-from aiohttp_session import Session, get_session, SESSION_KEY
+from aiohttp_session import Session, get_session, SESSION_KEY, STORAGE_KEY
 
 
 async def test_get_stored_session():
@@ -19,3 +19,16 @@ async def test_session_is_not_stored():
 
     with pytest.raises(RuntimeError):
         await get_session(req)
+
+
+async def test_storage_returns_not_session_on_load_session():
+    req = make_mocked_request('GET', '/')
+
+    class Storage():
+        async def load_session(self, request):
+            return None
+
+    req[STORAGE_KEY] = Storage()
+
+    with pytest.raises(RuntimeError):
+        await get_session(req)

tests/test_session_middleware.py

@@ -0,0 +1,8 @@
+import pytest
+
+from aiohttp_session import session_middleware
+
+
+async def test_session_middleware_bad_storage():
+    with pytest.raises(RuntimeError):
+        session_middleware(None)