Support brotlicffi alternatively to brotli (#7611)

## What do these changes do?

Support the brotlicffi implementation as an alternative to brotli. This
is necessary since the current version of brotli (as of 1.1.0) does not
work on PyPy. This uses the approach of preferring brotlicffi over
brotli in imports, and listing brotli or brotlicffi depending on the
Python implementation in dependencies, as recommended in brotlicffi
documentation:

https://pypi.org/project/brotlicffi/1.1.0.0/#using-brotlicffi-in-projects

.mypy.ini

@@ -35,6 +35,9 @@ ignore_missing_imports = True
 [mypy-brotli]
 ignore_missing_imports = True
 
+[mypy-brotlicffi]
+ignore_missing_imports = True
+
 [mypy-gunicorn.*]
 ignore_missing_imports = True
 

CHANGES/7611.feature

@@ -0,0 +1 @@
+Support using ``brotlicffi`` Python package alternatively to ``brotli``, as the latter does not work on PyPy.

aiohttp/compression_utils.py

@@ -4,7 +4,10 @@
 from typing import Optional, cast
 
 try:
-    import brotli
+    try:
+        import brotlicffi as brotli
+    except ImportError:
+        import brotli
 
     HAS_BROTLI = True
 except ImportError:  # pragma: no cover

docs/client_quickstart.rst

@@ -187,7 +187,8 @@ The ``gzip`` and ``deflate`` transfer-encodings are automatically
 decoded for you.
 
 You can enable ``brotli`` transfer-encodings support,
-just install  `Brotli <https://pypi.org/project/Brotli>`_.
+just install `Brotli <https://pypi.org/project/Brotli/>`_
+or `brotlicffi <https://pypi.org/project/brotlicffi/>`_.
 
 JSON Request
 ============

docs/glossary.rst

@@ -40,6 +40,13 @@
 
       https://pypi.org/project/Brotli/
 
+   brotlicffi
+
+      An alternative implementation of :term:`Brotli` built using the CFFI
+      library. This implementation supports PyPy correctly.
+
+      https://pypi.org/project/brotlicffi/
+
    callable
 
       Any object that can be called. Use :func:`callable` to check

docs/index.rst

@@ -158,7 +158,8 @@ Dependencies
 
      $ pip install aiodns
 
-- *Optional* :term:`Brotli` for brotli (:rfc:`7932`) client compression support.
+- *Optional* :term:`Brotli` or :term:`brotlicffi` for brotli (:rfc:`7932`)
+  client compression support.
 
   .. code-block:: bash
 

docs/spelling_wordlist.txt

@@ -40,6 +40,7 @@ boolean
 botocore
 brotli
 Brotli
+brotlicffi
 brotlipy
 bugfix
 Bugfixes

requirements/runtime-deps.in

@@ -6,4 +6,5 @@ yarl >= 1.0, < 2.0
 frozenlist >= 1.1.1
 aiosignal >= 1.1.2
 aiodns >= 1.1; sys_platform=="linux" or sys_platform=="darwin"
-Brotli
+Brotli; platform_python_implementation == 'CPython'
+brotlicffi; platform_python_implementation != 'CPython'

setup.cfg

@@ -62,7 +62,8 @@ install_requires =
 speedups =
   # required c-ares (aiodns' backend) will not build on windows
   aiodns >= 1.1; sys_platform=="linux" or sys_platform=="darwin"
-  Brotli
+  Brotli; platform_python_implementation == 'CPython'
+  brotlicffi; platform_python_implementation != 'CPython'
 
 [options.packages.find]
 exclude =

tests/test_http_parser.py

@@ -22,7 +22,10 @@
 )
 
 try:
-    import brotli
+    try:
+        import brotlicffi as brotli
+    except ImportError:
+        import brotli
 except ImportError:
     brotli = None
 

tests/test_web_functional.py

@@ -8,7 +8,6 @@
 from typing import Any, Optional
 from unittest import mock
 
-import brotli
 import pytest
 from multidict import CIMultiDictProxy, MultiDict
 from yarl import URL
@@ -19,6 +18,11 @@
 from aiohttp.test_utils import make_mocked_coro
 from aiohttp.typedefs import Handler
 
+try:
+    import brotlicffi as brotli
+except ImportError:
+    import brotli
+
 try:
     import ssl
 except ImportError: