noxfile-template.py

# Copyright 2019 Google LLC
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#      http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# 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 __future__ import print_function

import os
from pathlib import Path

import nox


# DO NOT EDIT - automatically generated.
# All versions used to tested samples.
ALL_VERSIONS = ["2.7", "3.6", "3.7", "3.8"]

# Any default versions that should be ignored.
IGNORED_VERSIONS = ["2.7"]

TESTED_VERSIONS = sorted([v for v in ALL_VERSIONS if v not in IGNORED_VERSIONS])

#
# Style Checks
#


# Ignore I202 "Additional newline in a section of imports." to accommodate
# region tags in import blocks. Since we specify an explicit ignore, we also
# have to explicitly ignore the list of default ignores:
# `E121,E123,E126,E226,E24,E704,W503,W504` as shown by `flake8 --help`.
def _determine_local_import_names(start_dir):
    """Determines all import names that should be considered "local".

    This is used when running the linter to insure that import order is
    properly checked.
    """
    file_ext_pairs = [os.path.splitext(path) for path in os.listdir(start_dir)]
    return [
        basename
        for basename, extension in file_ext_pairs
        if extension == ".py"
        or os.path.isdir(os.path.join(start_dir, basename))
        and basename not in ("__pycache__")
    ]


FLAKE8_COMMON_ARGS = [
    "--show-source",
    "--builtin=gettext",
    "--max-complexity=20",
    "--import-order-style=google",
    "--exclude=.nox,.cache,env,lib,generated_pb2,*_pb2.py,*_pb2_grpc.py",
    "--ignore=E121,E123,E126,E203,E226,E24,E266,E501,E704,W503,W504,I100,I201,I202",
    "--max-line-length=88",
]


@nox.session
def lint(session):
    session.install("flake8", "flake8-import-order")

    local_names = _determine_local_import_names(".")
    args = FLAKE8_COMMON_ARGS + [
        "--application-import-names",
        ",".join(local_names),
        ".",
    ]
    session.run("flake8", *args)


#
# Sample Tests
#


PYTEST_COMMON_ARGS = ["--junitxml=sponge_log.xml"]


def _session_tests(session, post_install=None):
    """Runs py.test for a particular project."""
    if os.path.exists("requirements.txt"):
        session.install("-r", "requirements.txt")

    if os.path.exists("requirements-test.txt"):
        session.install("-r", "requirements-test.txt")

    if post_install:
        post_install(session)

    session.run(
        "pytest",
        *(PYTEST_COMMON_ARGS + session.posargs),
        # Pytest will return 5 when no tests are collected. This can happen
        # on travis where slow and flaky tests are excluded.
        # See http://doc.pytest.org/en/latest/_modules/_pytest/main.html
        success_codes=[0, 5]
    )


@nox.session(python=ALL_VERSIONS)
def py(session):
    """Runs py.test for a sample using the specified version of Python."""
    if session.python in TESTED_VERSIONS:
        _session_tests(session)
    else:
        print("SKIPPED: {} tests are disabled for this sample.".format(session.python))


#
# Readmegen
#


def _get_repo_root():
    """ Returns the root folder of the project. """
    # Get root of this repository. Assume we don't have directories nested deeper than 10 items.
    p = Path(os.getcwd())
    for i in range(10):
        if p is None:
            break
        if Path(p / ".git").exists():
            return str(p)
        p = p.parent
    raise Exception("Unable to detect repository root.")


GENERATED_READMES = sorted([x for x in Path(".").rglob("*.rst.in")])


@nox.session
@nox.parametrize("path", GENERATED_READMES)
def readmegen(session, path):
    """(Re-)generates the readme for a sample."""
    session.install("jinja2", "pyyaml")
    dir_ = os.path.dirname(path)

    if os.path.exists(os.path.join(dir_, "requirements.txt")):
        session.install("-r", os.path.join(dir_, "requirements.txt"))

    in_file = os.path.join(dir_, "README.rst.in")
    session.run(
        "python", _get_repo_root() + "/scripts/readme-gen/readme_gen.py", in_file
    )