From 2fa1b3926f78c145b826729333aa568cc4eac186 Mon Sep 17 00:00:00 2001
From: Jordan Cook <jordan.cook@pioneer.com>
Date: Mon, 26 Jul 2021 18:06:35 -0500
Subject: [PATCH] WIP: Fix parsing HTTP dates from response headers

---
 HISTORY.md                            | 5 +++++
 aiohttp_client_cache/__init__.py      | 2 +-
 aiohttp_client_cache/cache_control.py | 7 ++++---
 aiohttp_client_cache/response.py      | 6 +++++-
 pyproject.toml                        | 2 +-
 test/conftest.py                      | 2 +-
 test/unit/test_response.py            | 5 +++++
 7 files changed, 22 insertions(+), 7 deletions(-)

diff --git a/HISTORY.md b/HISTORY.md
index b8fcf0b..2df73df 100644
--- a/HISTORY.md
+++ b/HISTORY.md
@@ -1,5 +1,10 @@
 # History
 
+## 0.4.3 (2021-07-27)
+* Fix bug in which reponse header `Expires` was used for cache expiration even with `cache_control=False`
+* Fix bug in which HTTP dates parsed from response headers weren't converted to UTC
+* Add handling for invalid timestamps in `CachedResponse.is_expired`
+
 ## 0.4.2 (2021-07-26)
 * Fix handling of `CachedResponse.encoding` when the response body is `None`
 
diff --git a/aiohttp_client_cache/__init__.py b/aiohttp_client_cache/__init__.py
index 2de53b6..84d7296 100644
--- a/aiohttp_client_cache/__init__.py
+++ b/aiohttp_client_cache/__init__.py
@@ -1,4 +1,4 @@
-__version__ = '0.4.2'
+__version__ = '0.4.3'
 
 # flake8: noqa: F401, F403
 try:
diff --git a/aiohttp_client_cache/cache_control.py b/aiohttp_client_cache/cache_control.py
index fc3a4c6..b9ad8c5 100644
--- a/aiohttp_client_cache/cache_control.py
+++ b/aiohttp_client_cache/cache_control.py
@@ -138,14 +138,15 @@ def coalesce(*values: Any, default=None) -> Any:
 def get_expiration_datetime(expire_after: ExpirationTime) -> Optional[datetime]:
     """Convert an expiration value in any supported format to an absolute datetime"""
     logger.debug(f'Determining expiration time based on: {expire_after}')
+    if isinstance(expire_after, str):
+        expire_after = parse_http_date(expire_after)
     if expire_after is None or expire_after == -1:
         return None
-    elif isinstance(expire_after, datetime):
+    if isinstance(expire_after, datetime):
         return to_utc(expire_after)
-    elif isinstance(expire_after, str):
-        return parse_http_date(expire_after)
 
     if not isinstance(expire_after, timedelta):
+        assert isinstance(expire_after, (int, float))
         expire_after = timedelta(seconds=expire_after)
     return datetime.utcnow() + expire_after
 
diff --git a/aiohttp_client_cache/response.py b/aiohttp_client_cache/response.py
index 163adf7..fde928e 100644
--- a/aiohttp_client_cache/response.py
+++ b/aiohttp_client_cache/response.py
@@ -131,7 +131,11 @@ def host(self) -> str:
     @property
     def is_expired(self) -> bool:
         """Determine if this cached response is expired"""
-        return self.expires is not None and datetime.utcnow() > self.expires
+        # If for any reason the expiration check fails, consider it expired and fetch a new response
+        try:
+            return self.expires is not None and datetime.utcnow() > self.expires
+        except (AttributeError, TypeError, ValueError):
+            return False
 
     @property
     def links(self) -> LinkMultiDict:
diff --git a/pyproject.toml b/pyproject.toml
index 5dbca7e..7af5192 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "aiohttp-client-cache"
-version = "0.4.2"
+version = "0.4.3"
 description = "Persistent cache for aiohttp requests"
 authors = ["Jordan Cook"]
 license = "MIT License"
diff --git a/test/conftest.py b/test/conftest.py
index e5e6a6b..43660b4 100644
--- a/test/conftest.py
+++ b/test/conftest.py
@@ -28,7 +28,7 @@
 ]
 
 HTTPDATE_STR = 'Fri, 16 APR 2021 21:13:00 GMT'
-HTTPDATE_DATETIME = datetime(2021, 4, 16, 21, 13, tzinfo=timezone.utc)
+HTTPDATE_DATETIME = datetime(2021, 4, 16, 21, 13)
 
 
 # Configure logging for pytest session
diff --git a/test/unit/test_response.py b/test/unit/test_response.py
index a38b952..e756794 100644
--- a/test/unit/test_response.py
+++ b/test/unit/test_response.py
@@ -68,6 +68,11 @@ async def test_is_expired(aiohttp_client):
     assert response.is_expired is True
 
 
+async def test_is_expired__invalid(aiohttp_client):
+    response = await get_test_response(aiohttp_client, expires='asdf')
+    assert response.is_expired is False
+
+
 async def test_content_disposition(aiohttp_client):
     response = await get_test_response(aiohttp_client, '/valid_url')
     assert response.content_disposition.type == 'attachment'