Make last_modified property round in one direction (aio-libs#5303)

CHANGES/5303.bugfix

@@ -0,0 +1 @@
+Make last_modified property round in one direction.

aiohttp/web_fileresponse.py

@@ -114,16 +114,20 @@ async def prepare(self, request: "BaseRequest") -> Optional[AbstractStreamWriter
         loop = asyncio.get_event_loop()
         st = await loop.run_in_executor(None, filepath.stat)
 
+        self.last_modified = st.st_mtime  # type: ignore
+        assert self.last_modified is not None
+
         modsince = request.if_modified_since
-        if modsince is not None and st.st_mtime <= modsince.timestamp():
+
+        if modsince is not None and self.last_modified <= modsince:
             self.set_status(HTTPNotModified.status_code)
             self._length_check = False
             # Delete any Content-Length headers provided by user. HTTP 304
             # should always have empty response body
             return await super().prepare(request)
 
         unmodsince = request.if_unmodified_since
-        if unmodsince is not None and st.st_mtime > unmodsince.timestamp():
+        if unmodsince is not None and self.last_modified > unmodsince:
             self.set_status(HTTPPreconditionFailed.status_code)
             return await super().prepare(request)
 
@@ -143,7 +147,7 @@ async def prepare(self, request: "BaseRequest") -> Optional[AbstractStreamWriter
         start = None
 
         ifrange = request.if_range
-        if ifrange is None or st.st_mtime <= ifrange.timestamp():
+        if ifrange is None or self.last_modified <= ifrange:
             # If-Range header check:
             # condition = cached date >= last modification date
             # return 206 if True else 200.
@@ -216,7 +220,6 @@ async def prepare(self, request: "BaseRequest") -> Optional[AbstractStreamWriter
             self.headers[hdrs.CONTENT_ENCODING] = encoding
         if gzip:
             self.headers[hdrs.VARY] = hdrs.ACCEPT_ENCODING
-        self.last_modified = st.st_mtime  # type: ignore
         self.content_length = count
 
         self.headers[hdrs.ACCEPT_RANGES] = "bytes"

aiohttp/web_response.py

@@ -259,7 +259,7 @@ def last_modified(
             self._headers.pop(hdrs.LAST_MODIFIED, None)
         elif isinstance(value, (int, float)):
             self._headers[hdrs.LAST_MODIFIED] = time.strftime(
-                "%a, %d %b %Y %H:%M:%S GMT", time.gmtime(math.ceil(value))
+                "%a, %d %b %Y %H:%M:%S GMT", time.gmtime(math.floor(value))
             )
         elif isinstance(value, datetime.datetime):
             self._headers[hdrs.LAST_MODIFIED] = time.strftime(

tests/test_web_response.py

@@ -10,6 +10,7 @@
 
 import aiosignal
 import pytest
+from freezegun import freeze_time
 from multidict import CIMultiDict, CIMultiDictProxy
 from re_assert import Matches
 
@@ -257,6 +258,17 @@ def test_last_modified_reset() -> None:
     assert resp.last_modified is None
 
 
+@freeze_time("2020-12-06 15:38:05.5555")
+def test_last_modified_round_consistency() -> None:
+    resp = StreamResponse()
+
+    resp.last_modified = datetime.datetime.now(tz=datetime.timezone.utc)
+    datetime_last_modified = resp.last_modified
+    resp.last_modified = datetime.datetime.now().timestamp()
+    float_last_modified = resp.last_modified
+    assert datetime_last_modified == float_last_modified
+
+
 async def test_start() -> None:
     req = make_request("GET", "/")
     resp = StreamResponse()

tests/test_web_sendfile.py

@@ -15,7 +15,8 @@ def test_using_gzip_if_header_present_and_file_available(loop: Any) -> None:
     gz_filepath.open = mock.mock_open()
     gz_filepath.is_file.return_value = True
     gz_filepath.stat.return_value = mock.MagicMock()
-    gz_filepath.stat.st_size = 1024
+    gz_filepath.stat.return_value.st_size = 1024
+    gz_filepath.stat.return_value.st_mtime = 0
 
     filepath = mock.Mock()
     filepath.name = "logo.png"
@@ -43,7 +44,8 @@ def test_gzip_if_header_not_present_and_file_available(loop: Any) -> None:
     filepath.open = mock.mock_open()
     filepath.with_name.return_value = gz_filepath
     filepath.stat.return_value = mock.MagicMock()
-    filepath.stat.st_size = 1024
+    filepath.stat.return_value.st_size = 1024
+    filepath.stat.return_value.st_mtime = 0
 
     file_sender = FileResponse(filepath)
     file_sender._sendfile = make_mocked_coro(None)  # type: ignore
@@ -66,7 +68,8 @@ def test_gzip_if_header_not_present_and_file_not_available(loop: Any) -> None:
     filepath.open = mock.mock_open()
     filepath.with_name.return_value = gz_filepath
     filepath.stat.return_value = mock.MagicMock()
-    filepath.stat.st_size = 1024
+    filepath.stat.return_value.st_size = 1024
+    filepath.stat.return_value.st_mtime = 0
 
     file_sender = FileResponse(filepath)
     file_sender._sendfile = make_mocked_coro(None)  # type: ignore
@@ -91,7 +94,8 @@ def test_gzip_if_header_present_and_file_not_available(loop: Any) -> None:
     filepath.open = mock.mock_open()
     filepath.with_name.return_value = gz_filepath
     filepath.stat.return_value = mock.MagicMock()
-    filepath.stat.st_size = 1024
+    filepath.stat.return_value.st_size = 1024
+    filepath.stat.return_value.st_mtime = 0
 
     file_sender = FileResponse(filepath)
     file_sender._sendfile = make_mocked_coro(None)  # type: ignore
@@ -109,7 +113,8 @@ def test_status_controlled_by_user(loop: Any) -> None:
     filepath.name = "logo.png"
     filepath.open = mock.mock_open()
     filepath.stat.return_value = mock.MagicMock()
-    filepath.stat.st_size = 1024
+    filepath.stat.return_value.st_size = 1024
+    filepath.stat.return_value.st_mtime = 0
 
     file_sender = FileResponse(filepath, status=203)
     file_sender._sendfile = make_mocked_coro(None)  # type: ignore