Adopt pep517 + try compile with cython

.github/workflows/create-wheels.yaml

@@ -15,6 +15,7 @@ jobs:
   # four jobs are defined make-wheel-win-osx, make-wheel-linux, make-source-dist and make-emulated-wheels
   # the wheels jobs do the the same steps, but linux wheels need to be build to target manylinux
   make-wheel-win-osx:
+    needs: make-source-dist
     name: ${{ matrix.python-version }}-${{ matrix.architecture }}-${{ matrix.os }}
     runs-on: ${{ matrix.os }}
     strategy:
@@ -50,14 +51,13 @@ jobs:
           architecture: ${{ matrix.architecture }}
 
       - name: Create wheel
-        # create the wheel using --no-use-pep517 since locally we have pyproject
-        # this flag should be removed once falcon supports pep517
-        # `--no-deps` is used to only generate the wheel for the current library. Redundant in falcon since it has no dependencies
+        # `--no-deps` is used to only generate the wheel for the current library.
+        # Redundant in falcon since it has no dependencies
         run: |
           python -m pip install --upgrade pip
           pip --version
-          pip install 'setuptools>=44' 'wheel>=0.34' 'cython>=0.29.21'
-          pip wheel -w dist --no-use-pep517 -v --no-deps .
+          pip install 'setuptools>=47' 'wheel>=0.34'
+          pip wheel -w dist -v --no-deps .
 
       - name: Check created wheel
         # - install the created wheel without using the pypi index
@@ -90,6 +90,7 @@ jobs:
           twine upload --skip-existing dist/*
 
   make-wheel-linux:
+    needs: make-source-dist
     # see also comments in the make-wheel-win-osx job for details on the steps
     name: ${{ matrix.python-version }}-${{ matrix.architecture }}-${{ matrix.os }}
     runs-on: ${{ matrix.os }}
@@ -142,11 +143,9 @@ jobs:
         # this action generates 3 wheels in dist/. linux manylinux1 and manylinux2010
         with:
           python-versions: ${{ matrix.python-version }}
-          build-requirements: "setuptools>=44 wheel>=0.34 cython>=0.29.21"
-          # Create the wheel using --no-use-pep517 since locally we have pyproject
-          # This flag should be removed once falcon supports pep517
+          build-requirements: "setuptools>=47 wheel>=0.34"
           # `--no-deps` is used to only generate the wheel for the current library. Redundant in falcon since it has no dependencies
-          pip-wheel-args: "-w ./dist --no-use-pep517 -v --no-deps"
+          pip-wheel-args: "-w ./dist -v --no-deps"
 
       - name: Create wheel for manylinux 2014
         # as previous step but for manylinux2014
@@ -156,8 +155,8 @@ jobs:
           # Remove previous original wheel just to be sure it is recreated. Should not be needed
           pre-build-command: "rm ./dist/*-linux*.whl"
           python-versions: ${{ matrix.python-version }}
-          build-requirements: "setuptools>=44 wheel>=0.34 cython>=0.29.21"
-          pip-wheel-args: "-w ./dist --no-use-pep517 -v --no-deps"
+          build-requirements: "setuptools>=47 wheel>=0.34"
+          pip-wheel-args: "-w ./dist -v --no-deps"
 
       - name: Check created wheel
         # - install the created wheel without using the pypi index
@@ -216,12 +215,10 @@ jobs:
           architecture: ${{ matrix.architecture }}
 
       - name: Create sdist
-        # TODO should we generate the c files? Only for pyx files or also for py files?
         run: |
           python -m pip install --upgrade pip
           pip --version
-          pip install setuptools>=44 wheel>=0.34 cython>=0.29.21
-          # cythonize -3 falcon/**/*.pyx
+          pip install setuptools>=47 wheel>=0.34
           python setup.py sdist --dist-dir dist
           python .github/workflows/scripts/verify_tag.py dist
 
@@ -243,6 +240,7 @@ jobs:
           twine upload --skip-existing dist/*
 
   make-emulated-wheels:
+    needs: make-source-dist
     # see also comments in the make-wheel-linux job for details on the steps
     name: ${{ matrix.python-version }}-${{ matrix.architecture }}
     runs-on: ubuntu-latest
@@ -289,8 +287,8 @@ jobs:
         # this action generates 2 wheels in dist/. linux manylinux1 and manylinux2010
         with:
           python-versions: ${{ matrix.python-version }}
-          build-requirements: "setuptools>=44 wheel>=0.34 cython>=0.29.21"
-          pip-wheel-args: "-w ./dist --no-use-pep517 -v --no-deps"
+          build-requirements: "setuptools>=47 wheel>=0.34"
+          pip-wheel-args: "-w ./dist -v --no-deps"
 
       - name: Check created wheel for arm
         if: ${{ matrix.architecture == 'aarch64' }}
@@ -314,8 +312,8 @@ jobs:
         # this action generates 2 wheels in dist/. linux manylinux1 and manylinux2010
         with:
           python-versions: ${{ matrix.python-version }}
-          build-requirements: "setuptools>=44 wheel>=0.34 cython>=0.29.21"
-          pip-wheel-args: "-w ./dist --no-use-pep517 -v --no-deps"
+          build-requirements: "setuptools>=47 wheel>=0.34"
+          pip-wheel-args: "-w ./dist -v --no-deps"
 
       - name: Check created wheel for s390x
         if: ${{ matrix.architecture == 's390x' }}

MANIFEST.in

@@ -6,7 +6,6 @@ include tox.ini
 include README.rst
 include LICENSE
 include docs/conf.py docs/Makefile
-exclude pyproject.toml
 graft docs/_static
 graft docs/_templates
 graft tools

README.rst

@@ -236,29 +236,30 @@ Or, to install the latest beta or release candidate, if any:
 In order to provide an extra speed boost, Falcon can compile itself with
 Cython. Wheels containing pre-compiled binaries are available from PyPI for
 several common platforms. However, if a wheel for your platform of choice is not
-available, you can choose to stick with the source distribution, or use the
-instructions below to cythonize Falcon for your environment.
-
-The following commands tell pip to install Cython, and then to invoke
-Falcon's ``setup.py``, which will in turn detect the presence of Cython
-and then compile (AKA cythonize) the Falcon framework with the system's
-default C compiler.
+available, you can install the source distribution. The installation process
+will automatically try to cythonize Falcon for your environment, falling back to 
+a normal pure-Python install if any issues are encountered during the 
+cythonization step:
 
 .. code:: bash
 
-    $ pip install cython
-    $ pip install --no-build-isolation --no-binary :all: falcon
-
-Note that ``--no-build-isolation`` is necessary to override pip's default
-PEP 517 behavior that can cause Cython not to be found in the build
-environment.
+    $ pip install --no-binary :all: falcon
 
 If you want to verify that Cython is being invoked, simply
-pass `-v` to pip in order to echo the compilation commands:
+pass the verbose flag `-v` to pip in order to echo the compilation commands.
+
+The cythonization step is only active when using the ``CPython`` Python
+implementation, so installing using ``PyPy`` will skip it.
+If you want to skip Cython compilation step and install
+the pure-Python version directly you can set the environment variable
+``FALCON_DISABLE_CYTHON`` to a non empty value before install:
 
 .. code:: bash
 
-    $ pip install -v --no-build-isolation --no-binary :all: falcon
+    $ FALCON_DISABLE_CYTHON=Y pip install -v --no-binary :all: falcon
+
+Please note that ``pip>=10`` is required to be able to install Falcon from
+source.
 
 **Installing on OS X**
 
@@ -335,7 +336,7 @@ available to your app without having to reinstall the package:
 .. code:: bash
 
     $ cd falcon
-    $ pip install --no-use-pep517 -e .
+    $ pip install -e .
 
 You can manually test changes to the Falcon framework by switching to the
 directory of the cloned repo and then running pytest:

pyproject.toml

@@ -1,3 +1,11 @@
+[build-system]
+    build-backend = "setuptools.build_meta"
+    requires = [
+        "setuptools>=47",
+        "wheel>=0.34",
+        "cython>=0.29.21; python_implementation == 'CPython'", # Skip cython when using pypy
+    ]
+
 [tool.towncrier]
     package = "falcon"
     package_dir = ""

setup.cfg

@@ -1,3 +1,72 @@
+[metadata]
+name = falcon
+version = attr: falcon.__version__
+description = An unladen web framework for building APIs and app backends.
+long_description_content_type = text/x-rst
+url = https://falconframework.org
+author = Kurt Griffiths
+author_email = mail@kgriffs.com
+license = Apache 2.0
+license_file = LICENSE
+classifiers =
+    Development Status :: 5 - Production/Stable
+    Environment :: Web Environment
+    Natural Language :: English
+    Intended Audience :: Developers
+    Intended Audience :: System Administrators
+    License :: OSI Approved :: Apache Software License
+    Operating System :: MacOS :: MacOS X
+    Operating System :: Microsoft :: Windows
+    Operating System :: POSIX
+    Topic :: Internet :: WWW/HTTP :: WSGI
+    Topic :: Software Development :: Libraries :: Application Frameworks
+    Programming Language :: Python
+    Programming Language :: Python :: Implementation :: CPython
+    Programming Language :: Python :: Implementation :: PyPy
+    Programming Language :: Python :: 3
+    Programming Language :: Python :: 3.5
+    Programming Language :: Python :: 3.6
+    Programming Language :: Python :: 3.7
+    Programming Language :: Python :: 3.8
+    Programming Language :: Python :: 3.9
+    Programming Language :: Cython
+keywords =
+    asgi
+    wsgi
+    web
+    api
+    framework
+    rest
+    http
+    cloud
+project_urls =
+    Documentation=https://falcon.readthedocs.io/en/stable/
+    Issue Tracker=https://github.com/falconry/falcon
+
+[options]
+zip_safe = False
+include_package_data = True
+packages = find:
+python_requires = >=3.5
+install_requires =
+tests_require =
+    testtools
+    requests
+    pyyaml
+    pytest
+    pytest-runner
+
+[options.packages.find]
+exclude =
+    examples
+    tests
+
+[options.entry_points]
+console_scripts =
+    falcon-bench = falcon.cmd.bench:main
+    falcon-inspect-app = falcon.cmd.inspect_app:main
+    falcon-print-routes = falcon.cmd.inspect_app:route_main
+
 [egg_info]
 # TODO replace
 tag_build = dev1