Remove support for Python 3.7 (#15851)

Fix #15836

.ci/scripts/calculate_jobs.py

@@ -29,11 +29,12 @@ def set_output(key: str, value: str):
 
 # First calculate the various trial jobs.
 #
-# For each type of test we only run on Py3.7 on PRs
+# For PRs, we only run each type of test with the oldest Python version supported (which
+# is Python 3.8 right now)
 
 trial_sqlite_tests = [
     {
-        "python-version": "3.7",
+        "python-version": "3.8",
         "database": "sqlite",
         "extras": "all",
     }
@@ -46,13 +47,13 @@ def set_output(key: str, value: str):
             "database": "sqlite",
             "extras": "all",
         }
-        for version in ("3.8", "3.9", "3.10", "3.11")
+        for version in ("3.9", "3.10", "3.11")
     )
 
 
 trial_postgres_tests = [
     {
-        "python-version": "3.7",
+        "python-version": "3.8",
         "database": "postgres",
         "postgres-version": "11",
         "extras": "all",
@@ -71,7 +72,7 @@ def set_output(key: str, value: str):
 
 trial_no_extra_tests = [
     {
-        "python-version": "3.7",
+        "python-version": "3.8",
         "database": "sqlite",
         "extras": "",
     }

.github/workflows/release-artifacts.yml

@@ -144,7 +144,7 @@ jobs:
 
       - name: Only build a single wheel on PR
         if: startsWith(github.ref, 'refs/pull/')
-        run: echo "CIBW_BUILD="cp37-manylinux_${{ matrix.arch }}"" >> $GITHUB_ENV
+        run: echo "CIBW_BUILD="cp38-manylinux_${{ matrix.arch }}"" >> $GITHUB_ENV
 
       - name: Build wheels
         run: python -m cibuildwheel --output-dir wheelhouse

.github/workflows/tests.yml

@@ -320,7 +320,7 @@ jobs:
 
       - uses: actions/setup-python@v4
         with:
-          python-version: '3.7'
+          python-version: '3.8'
 
       - name: Prepare old deps
         if: steps.cache-poetry-old-deps.outputs.cache-hit != 'true'
@@ -362,7 +362,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: ["pypy-3.7"]
+        python-version: ["pypy-3.8"]
         extras: ["all"]
 
     steps:
@@ -477,7 +477,7 @@ jobs:
     strategy:
       matrix:
         include:
-          - python-version: "3.7"
+          - python-version: "3.8"
             postgres-version: "11"
 
           - python-version: "3.11"

changelog.d/15851.removal

@@ -0,0 +1 @@
+Remove support for Python 3.7.

docker/Dockerfile-dhvirtualenv

@@ -28,12 +28,12 @@ FROM docker.io/library/${distro} as builder
 
 RUN apt-get update -qq -o Acquire::Languages=none
 RUN env DEBIAN_FRONTEND=noninteractive apt-get install \
-        -yqq --no-install-recommends \
-        build-essential \
-        ca-certificates \
-        devscripts \
-        equivs \
-        wget
+    -yqq --no-install-recommends \
+    build-essential \
+    ca-certificates \
+    devscripts \
+    equivs \
+    wget
 
 # fetch and unpack the package
 # We are temporarily using a fork of dh-virtualenv due to an incompatibility with Python 3.11, which ships with
@@ -62,33 +62,29 @@ FROM docker.io/library/${distro}
 ARG distro=""
 ENV distro ${distro}
 
-# Python < 3.7 assumes LANG="C" means ASCII-only and throws on printing unicode
-# http://bugs.python.org/issue19846
-ENV LANG C.UTF-8
-
 # Install the build dependencies
 #
 # NB: keep this list in sync with the list of build-deps in debian/control
 # TODO: it would be nice to do that automatically.
 RUN apt-get update -qq -o Acquire::Languages=none \
     && env DEBIAN_FRONTEND=noninteractive apt-get install \
-        -yqq --no-install-recommends -o Dpkg::Options::=--force-unsafe-io \
-        build-essential \
-        curl \
-        debhelper \
-        devscripts \
-        libsystemd-dev \
-        lsb-release \
-        pkg-config \
-        python3-dev \
-        python3-pip \
-        python3-setuptools \
-        python3-venv \
-        sqlite3 \
-        libpq-dev \
-        libicu-dev \
-        pkg-config \
-        xmlsec1
+    -yqq --no-install-recommends -o Dpkg::Options::=--force-unsafe-io \
+    build-essential \
+    curl \
+    debhelper \
+    devscripts \
+    libsystemd-dev \
+    lsb-release \
+    pkg-config \
+    python3-dev \
+    python3-pip \
+    python3-setuptools \
+    python3-venv \
+    sqlite3 \
+    libpq-dev \
+    libicu-dev \
+    pkg-config \
+    xmlsec1
 
 # Install rust and ensure it's in the PATH
 ENV RUSTUP_HOME=/rust

docs/setup/installation.md

@@ -200,7 +200,7 @@ When following this route please make sure that the [Platform-specific prerequis
 System requirements:
 
 - POSIX-compliant system (tested on Linux & OS X)
-- Python 3.7 or later, up to Python 3.11.
+- Python 3.8 or later, up to Python 3.11.
 - At least 1GB of free RAM if you want to join large public rooms like #matrix:matrix.org
 
 If building on an uncommon architecture for which pre-built wheels are

docs/upgrade.md

@@ -87,6 +87,18 @@ process, for example:
     wget https://packages.matrix.org/debian/pool/main/m/matrix-synapse-py3/matrix-synapse-py3_1.3.0+stretch1_amd64.deb
     dpkg -i matrix-synapse-py3_1.3.0+stretch1_amd64.deb
     ```
+
+# Upgrading to v1.88.0
+
+## Minimum supported Python version
+
+The minimum supported Python version has been increased from v3.7 to v3.8.
+You will need Python 3.8 to run Synapse v1.88.0 (due out July 18th, 2023).
+
+If you use current versions of the Matrix.org-distributed Debian
+packages or Docker images, no action is required.
+
+
 # Upgrading to v1.86.0
 
 ## Minimum supported Rust version

pyproject.toml

@@ -147,7 +147,7 @@ synapse_review_recent_signups = "synapse._scripts.review_recent_signups:main"
 update_synapse_database = "synapse._scripts.update_synapse_database:main"
 
 [tool.poetry.dependencies]
-python = "^3.7.1"
+python = "^3.8.0"
 
 # Mandatory Dependencies
 # ----------------------
@@ -203,9 +203,6 @@ ijson = ">=3.1.4"
 matrix-common = "^1.3.0"
 # We need packaging.requirements.Requirement, added in 16.1.
 packaging = ">=16.1"
-# At the time of writing, we only use functions from the version `importlib.metadata`
-# which shipped in Python 3.8. This corresponds to version 1.4 of the backport.
-importlib_metadata = { version = ">=1.4", python = "<3.8" }
 # This is the most recent version of Pydantic with available on common distros.
 # We are currently incompatible with >=2.0.0: (https://github.com/matrix-org/synapse/issues/15858)
 pydantic = "^1.7.4"

synapse/__init__.py

@@ -25,8 +25,8 @@
 from synapse.util.stringutils import strtobool
 
 # Check that we're not running on an unsupported Python version.
-if sys.version_info < (3, 7):
-    print("Synapse requires Python 3.7 or above.")
+if sys.version_info < (3, 8):
+    print("Synapse requires Python 3.8 or above.")
     sys.exit(1)
 
 # Allow using the asyncio reactor via env var.

synapse/util/check_dependencies.py

@@ -21,16 +21,13 @@
 """
 
 import logging
+from importlib import metadata
 from typing import Iterable, NamedTuple, Optional
 
 from packaging.requirements import Requirement
 
 DISTRIBUTION_NAME = "matrix-synapse"
 
-try:
-    from importlib import metadata
-except ImportError:
-    import importlib_metadata as metadata  # type: ignore[no-redef]
 
 __all__ = ["check_requirements"]
 

tests/metrics/test_metrics.py

@@ -12,19 +12,13 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+from importlib import metadata
 from typing import Dict, Tuple
-
-from typing_extensions import Protocol
-
-try:
-    from importlib import metadata
-except ImportError:
-    import importlib_metadata as metadata  # type: ignore[no-redef]
-
 from unittest.mock import patch
 
 from pkg_resources import parse_version
 from prometheus_client.core import Sample
+from typing_extensions import Protocol
 
 from synapse.app._base import _set_prometheus_client_use_created_metrics
 from synapse.metrics import REGISTRY, InFlightGauge, generate_latest