[1.26] Fix running CPython 2.7 tests in CI (#3137)

.github/workflows/ci.yml

@@ -29,14 +29,12 @@ jobs:
  strategy:
  fail-fast: false
  matrix:
- python-version: ["2.7", "3.6", "3.7", "3.8", "3.9", "3.10"]
+ python-version: ["3.6", "3.7", "3.8", "3.9", "3.10"]
  os: [macos-11, windows-latest, ubuntu-latest]
  experimental: [false]
  nox-session: ['']
  exclude:
- # GitHub Actions dropped support for Python 2.7 and 3.7 in Ubuntu 22.04
- - python-version: "2.7"
- os: ubuntu-latest
+ # actions/setup-python dropped support for 3.6 in Ubuntu 22.04
  - python-version: "3.6"
  os: ubuntu-latest
  # Python 3.7 does not fully support OpenSSL 3, the default on Ubuntu 22.04
@@ -45,7 +43,7 @@ jobs:
  os: ubuntu-latest
  include:
  - python-version: "2.7"
- os: ubuntu-20.04
+ os: ubuntu-latest
  experimental: false
  nox-session: ''
  - python-version: "3.6"
@@ -89,10 +87,20 @@ jobs:
  uses: actions/checkout@v2
 
  - name: Set Up Python - ${{ matrix.python-version }}
+ if: matrix.python-version != '2.7'
  uses: actions/setup-python@v4
  with:
  python-version: ${{ matrix.python-version }}
 
+ # Unfortunately, actions/setup-python does not support CPython 2.7.
+ - name: Set Up Python - 2.7
+ if: matrix.python-version == '2.7'
+ run: |
+ sudo apt update
+ sudo apt install python2.7-dev python-is-python3
+ curl https://bootstrap.pypa.io/pip/2.7/get-pip.py --output get-pip.py
+ sudo python2.7 get-pip.py
+
  - name: Set Up Python 3 to run nox
  if: matrix.python-version == '2.7' || matrix.python-version == 'pypy2.7'
  uses: actions/setup-python@v4

ci/run_tests.sh

@@ -3,7 +3,7 @@
 
 if [[ "${NOX_SESSION}" == "app_engine" ]]; then
  export GAE_SDK_PATH=$HOME/.cache/google_appengine
- python2 -m pip install gcp-devrel-py-tools==0.0.16
+ python2.7 -m pip install gcp-devrel-py-tools==0.0.16
  gcp-devrel-py-tools download-appengine-sdk "$(dirname ${GAE_SDK_PATH})"
 fi
 

noxfile.py

@@ -55,7 +55,8 @@ def google_brotli(session):
  # https://pypi.org/project/Brotli/ is the Google version of brotli, so
  # install it separately and don't install our brotli extra (which installs
  # brotlipy).
- session.install("brotli")
+ # https://github.com/google/brotli/issues/1074
+ session.install("brotli==1.0.9" if session.python == "2.7" else "brotli")
  tests_impl(session, extras="socks,secure")
 
 

src/urllib3/connection.py

@@ -437,7 +437,7 @@ def connect(self):
  and self.ssl_version is None
  and hasattr(self.sock, "version")
  and self.sock.version() in {"TLSv1", "TLSv1.1"}
- ):
+ ): # Defensive:
  warnings.warn(
  "Negotiating TLSv1/TLSv1.1 by default is deprecated "
  "and will be disabled in urllib3 v2.0.0. Connecting to "