Add strategy argument to StreamResponse.enable_compression() meth…

…od (#6257)

CHANGES/6257.feature

@@ -0,0 +1,4 @@
+Added ``strategy`` parameter to :meth:`aiohttp.web.StreamResponse.enable_compression`
+The value of this parameter is passed to the :func:`zlib.compressobj` function, allowing people
+to use a more sufficient compression algorithm for their data served by :mod:`aiohttp.web`
+-- by :user:`shootkin`

CONTRIBUTORS.txt

@@ -208,6 +208,7 @@ Kevin Samuel
 Kimmo Parviainen-Jalanko
 Kirill Klenov
 Kirill Malovitsa
+Konstantin Shutkin
 Konstantin Valetov
 Krzysztof Blazewicz
 Kyrylo Perevozchikov

aiohttp/abc.py

@@ -1,5 +1,6 @@
 import logging
 import socket
+import zlib
 from abc import ABC, abstractmethod
 from collections.abc import Sized
 from http.cookies import BaseCookie, Morsel
@@ -204,7 +205,9 @@ async def drain(self) -> None:
         """Flush the write buffer."""
 
     @abstractmethod
-    def enable_compression(self, encoding: str = "deflate") -> None:
+    def enable_compression(
+        self, encoding: str = "deflate", strategy: int = zlib.Z_DEFAULT_STRATEGY
+    ) -> None:
         """Enable HTTP body compression"""
 
     @abstractmethod

aiohttp/web_response.py

@@ -6,6 +6,7 @@
 import math
 import time
 import warnings
+import zlib
 from concurrent.futures import Executor
 from http import HTTPStatus
 from typing import (
@@ -77,6 +78,7 @@ class StreamResponse(BaseClass, HeadersMixin, CookieMixin):
         "_chunked",
         "_compression",
         "_compression_force",
+        "_compression_strategy",
         "_req",
         "_payload_writer",
         "_eof_sent",
@@ -105,6 +107,7 @@ def __init__(
         self._keep_alive: Optional[bool] = None
         self._chunked = False
         self._compression = False
+        self._compression_strategy: int = zlib.Z_DEFAULT_STRATEGY
         self._compression_force: Optional[ContentCoding] = None
 
         self._req: Optional[BaseRequest] = None
@@ -184,10 +187,15 @@ def enable_chunked_encoding(self) -> None:
                 "You can't enable chunked encoding when a content length is set"
             )
 
-    def enable_compression(self, force: Optional[ContentCoding] = None) -> None:
+    def enable_compression(
+        self,
+        force: Optional[ContentCoding] = None,
+        strategy: int = zlib.Z_DEFAULT_STRATEGY,
+    ) -> None:
         """Enables response compression encoding."""
         self._compression = True
         self._compression_force = force
+        self._compression_strategy = strategy
 
     @property
     def headers(self) -> "CIMultiDict[str]":
@@ -319,7 +327,9 @@ async def _do_start_compression(self, coding: ContentCoding) -> None:
         if coding != ContentCoding.identity:
             assert self._payload_writer is not None
             self._headers[hdrs.CONTENT_ENCODING] = coding.value
-            self._payload_writer.enable_compression(coding.value)
+            self._payload_writer.enable_compression(
+                coding.value, self._compression_strategy
+            )
             # Compressed payload may have different content length,
             # remove the header
             self._headers.popall(hdrs.CONTENT_LENGTH, None)

docs/web_reference.rst

@@ -649,7 +649,7 @@ and :ref:`aiohttp-web-signals` handlers::
 
       .. seealso:: :meth:`enable_compression`
 
-   .. method:: enable_compression(force=None)
+   .. method:: enable_compression(force=None, strategy=zlib.Z_DEFAULT_STRATEGY)
 
       Enable compression.
 
@@ -659,6 +659,9 @@ and :ref:`aiohttp-web-signals` handlers::
       *Accept-Encoding* is not checked if *force* is set to a
       :class:`ContentCoding`.
 
+      *strategy* accepts a :mod:`zlib` compression strategy.
+      See :func:`zlib.compressobj` for possible values.
+
       .. seealso:: :attr:`compression`
 
    .. attribute:: chunked

tests/test_web_response.py

@@ -6,6 +6,7 @@
 import json
 import re
 import weakref
+import zlib
 from concurrent.futures import ThreadPoolExecutor
 from typing import Any, AsyncIterator, Optional
 from unittest import mock
@@ -421,7 +422,7 @@ async def test_compression_default_coding() -> None:
 
     msg = await resp.prepare(req)
 
-    msg.enable_compression.assert_called_with("deflate")
+    msg.enable_compression.assert_called_with("deflate", zlib.Z_DEFAULT_STRATEGY)
     assert "deflate" == resp.headers.get(hdrs.CONTENT_ENCODING)
     assert msg.filter is not None
 
@@ -436,7 +437,7 @@ async def test_force_compression_deflate() -> None:
     assert resp.compression
 
     msg = await resp.prepare(req)
-    msg.enable_compression.assert_called_with("deflate")
+    msg.enable_compression.assert_called_with("deflate", zlib.Z_DEFAULT_STRATEGY)
     assert "deflate" == resp.headers.get(hdrs.CONTENT_ENCODING)
 
 
@@ -448,7 +449,7 @@ async def test_force_compression_no_accept_deflate() -> None:
     assert resp.compression
 
     msg = await resp.prepare(req)
-    msg.enable_compression.assert_called_with("deflate")
+    msg.enable_compression.assert_called_with("deflate", zlib.Z_DEFAULT_STRATEGY)
     assert "deflate" == resp.headers.get(hdrs.CONTENT_ENCODING)
 
 
@@ -462,7 +463,7 @@ async def test_force_compression_gzip() -> None:
     assert resp.compression
 
     msg = await resp.prepare(req)
-    msg.enable_compression.assert_called_with("gzip")
+    msg.enable_compression.assert_called_with("gzip", zlib.Z_DEFAULT_STRATEGY)
     assert "gzip" == resp.headers.get(hdrs.CONTENT_ENCODING)
 
 
@@ -474,7 +475,7 @@ async def test_force_compression_no_accept_gzip() -> None:
     assert resp.compression
 
     msg = await resp.prepare(req)
-    msg.enable_compression.assert_called_with("gzip")
+    msg.enable_compression.assert_called_with("gzip", zlib.Z_DEFAULT_STRATEGY)
     assert "gzip" == resp.headers.get(hdrs.CONTENT_ENCODING)