aio-libs#2304 add max_line_site, max_headers and max_field_size argum…

…ents to ClientSession

CHANGES/2304.feature

@@ -0,0 +1 @@
+Support setting response header parameters max_line_size, max_headers and max_field_size.

aiohttp/client.py

@@ -191,6 +191,9 @@ class ClientSession:
         "_ws_response_class",
         "_trace_configs",
         "_read_bufsize",
+        "_max_line_size",
+        "_max_headers",
+        "_max_field_size",
     )
 
     def __init__(
@@ -218,6 +221,9 @@ def __init__(
         requote_redirect_url: bool = True,
         trace_configs: Optional[List[TraceConfig]] = None,
         read_bufsize: int = 2**16,
+        max_line_size: int = 8190,
+        max_headers: int = 32768,
+        max_field_size: int = 8190,
     ) -> None:
         if base_url is None or isinstance(base_url, URL):
             self._base_url: Optional[URL] = base_url
@@ -266,6 +272,9 @@ def __init__(
         self._trust_env = trust_env
         self._requote_redirect_url = requote_redirect_url
         self._read_bufsize = read_bufsize
+        self._max_line_size = max_line_size
+        self._max_headers = max_headers
+        self._max_field_size = max_field_size
 
         # Convert to list of tuples
         if headers:
@@ -351,6 +360,9 @@ async def _request(
         proxy_headers: Optional[LooseHeaders] = None,
         trace_request_ctx: Optional[SimpleNamespace] = None,
         read_bufsize: Optional[int] = None,
+        max_line_size: Optional[int] = None,
+        max_headers: Optional[int] = None,
+        max_field_size: Optional[int] = None,
     ) -> ClientResponse:
 
         # NOTE: timeout clamps existing connect and read timeouts.  We cannot
@@ -411,6 +423,15 @@ async def _request(
         if read_bufsize is None:
             read_bufsize = self._read_bufsize
 
+        if max_line_size is None:
+            max_line_size = self._max_line_size
+
+        if max_headers is None:
+            max_headers = self._max_headers
+
+        if max_field_size is None:
+            max_field_size = self._max_field_size
+
         traces = [
             Trace(
                 self,
@@ -516,6 +537,9 @@ async def _request(
                         read_timeout=real_timeout.sock_read,
                         read_bufsize=read_bufsize,
                         timeout_ceil_threshold=self._connector._timeout_ceil_threshold,
+                        max_line_size=max_line_size,
+                        max_headers=max_headers,
+                        max_field_size=max_field_size,
                     )
 
                     try:
@@ -1193,6 +1217,9 @@ def request(
     version: HttpVersion = http.HttpVersion11,
     connector: Optional[BaseConnector] = None,
     read_bufsize: Optional[int] = None,
+    max_line_size: int = 8190,
+    max_headers: int = 32768,
+    max_field_size: int = 8190,
 ) -> _SessionRequestContextManager:
     """Constructs and sends a request.
 
@@ -1263,6 +1290,9 @@ def request(
             proxy=proxy,
             proxy_auth=proxy_auth,
             read_bufsize=read_bufsize,
+            max_line_size=max_line_size,
+            max_headers=max_headers,
+            max_field_size=max_field_size,
         ),
         session,
     )

aiohttp/client_proto.py

@@ -153,6 +153,9 @@ def set_response_params(
         read_timeout: Optional[float] = None,
         read_bufsize: int = 2**16,
         timeout_ceil_threshold: float = 5,
+        max_line_size: int = 8190,
+        max_headers: int = 32768,
+        max_field_size: int = 8190,
     ) -> None:
         self._skip_payload = skip_payload
 
@@ -170,6 +173,9 @@ def set_response_params(
             response_with_body=not skip_payload,
             read_until_eof=read_until_eof,
             auto_decompress=auto_decompress,
+            max_line_size=max_line_size,
+            max_headers=max_headers,
+            max_field_size=max_field_size,
         )
 
         if self._tail:

docs/client_reference.rst

@@ -52,7 +52,10 @@ The client session supports the context manager protocol for self closing.
                          read_bufsize=2**16, \
                          requote_redirect_url=False, \
                          trust_env=False, \
-                         trace_configs=None)
+                         trace_configs=None, \
+                         max_line_size=8190, \
+                         max_headers=32768, \
+                         max_field_size=8190)
 
    The class for creating client sessions and making requests.
 
@@ -201,6 +204,12 @@ The client session supports the context manager protocol for self closing.
                          disabling.  See :ref:`aiohttp-client-tracing-reference` for
                          more information.
 
+   :param max_line_size: The maximum length allowed for the HTTP response reason field.
+
+   :param max_headers: The maximum number of response headers allowed.
+
+   :param max_field_size: The maximum length allowed for response header values.
+
    .. attribute:: closed
 
       ``True`` if the session has been closed, ``False`` otherwise.
@@ -338,7 +347,10 @@ The client session supports the context manager protocol for self closing.
                          proxy=None, proxy_auth=None,\
                          timeout=sentinel, ssl=None, \
                          verify_ssl=None, fingerprint=None, \
-                         ssl_context=None, proxy_headers=None)
+                         ssl_context=None, proxy_headers=None, \
+                         max_line_size=8190, \
+                         max_headers=32768, \
+                         max_field_size=8190)
       :async-with:
       :coroutine:
       :noindex:
@@ -510,6 +522,12 @@ The client session supports the context manager protocol for self closing.
 
          .. versionadded:: 3.0
 
+      :param max_line_size: The maximum length allowed for the HTTP response reason field.
+
+      :param max_headers: The maximum number of response headers allowed.
+
+      :param max_field_size: The maximum length allowed for response header values.
+
       :return ClientResponse: a :class:`client response <ClientResponse>`
          object.
 

tests/test_client_functional.py

@@ -3028,3 +3028,173 @@ async def handler(request):
         assert resp.status == 200
         assert await resp.text() == "ok"
         assert resp.headers["Content-Type"] == "text/plain; charset=utf-8"
+
+
+async def test_max_field_size_session_default(aiohttp_client: Any) -> None:
+    async def handler(request):
+        return web.Response(headers={"Custom": "x" * 8190})
+
+    app = web.Application()
+    app.add_routes([web.get("/", handler)])
+
+    client = await aiohttp_client(app)
+
+    async with await client.get("/") as resp:
+        assert resp.headers["Custom"] == "x" * 8190
+
+
+async def test_max_field_size_session_default_fail(aiohttp_client: Any) -> None:
+    async def handler(request):
+        return web.Response(headers={"Custom": "x" * 8191})
+
+    app = web.Application()
+    app.add_routes([web.get("/", handler)])
+
+    client = await aiohttp_client(app)
+    with pytest.raises(aiohttp.ClientResponseError):
+        await client.get("/")
+
+
+async def test_max_field_size_session_explicit(aiohttp_client: Any) -> None:
+    async def handler(request):
+        return web.Response(headers={"Custom": "x" * 8191})
+
+    app = web.Application()
+    app.add_routes([web.get("/", handler)])
+
+    client = await aiohttp_client(app, max_field_size=8191)
+
+    async with await client.get("/") as resp:
+        assert resp.headers["Custom"] == "x" * 8191
+
+
+async def test_max_field_size_request_explicit(aiohttp_client: Any) -> None:
+    async def handler(request):
+        return web.Response(headers={"Custom": "x" * 8191})
+
+    app = web.Application()
+    app.add_routes([web.get("/", handler)])
+
+    client = await aiohttp_client(app)
+
+    async with await client.get("/", max_field_size=8191) as resp:
+        assert resp.headers["Custom"] == "x" * 8191
+
+
+async def test_max_line_size_session_default(aiohttp_client: Any) -> None:
+    async def handler(request):
+        return web.Response(status=200, reason="x" * 8190)
+
+    app = web.Application()
+    app.add_routes([web.get("/", handler)])
+
+    client = await aiohttp_client(app)
+
+    async with await client.get("/") as resp:
+        assert resp.reason == "x" * 8190
+
+
+async def test_max_line_size_session_default_fail(aiohttp_client: Any) -> None:
+    async def handler(request):
+        return web.Response(status=200, reason="x" * 8192)
+
+    app = web.Application()
+    app.add_routes([web.get("/", handler)])
+
+    client = await aiohttp_client(app)
+    with pytest.raises(aiohttp.ClientResponseError):
+        await client.get("/")
+
+
+async def test_max_line_size_session_explicit(aiohttp_client: Any) -> None:
+    async def handler(request):
+        return web.Response(status=200, reason="x" * 8191)
+
+    app = web.Application()
+    app.add_routes([web.get("/", handler)])
+
+    client = await aiohttp_client(app, max_line_size=8191)
+
+    async with await client.get("/") as resp:
+        assert resp.reason == "x" * 8191
+
+
+async def test_max_line_size_request_explicit(aiohttp_client: Any) -> None:
+    async def handler(request):
+        return web.Response(status=200, reason="x" * 8191)
+
+    app = web.Application()
+    app.add_routes([web.get("/", handler)])
+
+    client = await aiohttp_client(app)
+
+    async with await client.get("/", max_line_size=8191) as resp:
+        assert resp.reason == "x" * 8191
+
+
+async def test_max_headers_session_default(aiohttp_client: Any) -> None:
+    async def handler(request):
+        # generate 32764 headers:
+        # 32768 (max_headers default) minus 4 headers which are set implicitly
+        # 'Content-Length', 'Content-Type', 'Date' and 'Server'
+        headers = MultiDict()
+        for x in range(32764):
+            headers.add(f"x-header-{x}", str(x))
+        return web.Response(headers=headers)
+
+    app = web.Application()
+    app.add_routes([web.get("/", handler)])
+
+    client = await aiohttp_client(app)
+
+    async with await client.get("/") as resp:
+        assert len(resp.headers) == 32768
+
+
+@pytest.mark.xfail
+async def test_max_headers_session_default_fail(aiohttp_client: Any) -> None:
+    async def handler(request):
+        headers = MultiDict()
+        for x in range(32769):
+            headers.add(f"x-header-{x}", str(x))
+        return web.Response(headers=headers)
+
+    app = web.Application()
+    app.add_routes([web.get("/", handler)])
+
+    client = await aiohttp_client(app)
+
+    with pytest.raises(aiohttp.ClientResponseError):
+        await client.get("/")
+
+
+async def test_max_headers_session_explicit(aiohttp_client: Any) -> None:
+    async def handler(request):
+        headers = MultiDict()
+        for x in range(32765):
+            headers.add(f"x-header-{x}", str(x))
+        return web.Response(headers=headers)
+
+    app = web.Application()
+    app.add_routes([web.get("/", handler)])
+
+    client = await aiohttp_client(app, max_headers=32769)
+
+    async with await client.get("/") as resp:
+        assert len(resp.headers) == 32769
+
+
+async def test_max_headers_request_explicit(aiohttp_client: Any) -> None:
+    async def handler(request):
+        headers = MultiDict()
+        for x in range(32765):
+            headers.add(f"x-header-{x}", str(x))
+        return web.Response(headers=headers)
+
+    app = web.Application()
+    app.add_routes([web.get("/", handler)])
+
+    client = await aiohttp_client(app)
+
+    async with await client.get("/", max_headers=32769) as resp:
+        assert len(resp.headers) == 32769