fix: require python 3.7+

.github/.OwlBot.lock.yaml

@@ -13,5 +13,5 @@
 # limitations under the License.
 docker:
   image: gcr.io/cloud-devrel-public-resources/owlbot-python:latest
-  digest: sha256:b2dc5f80edcf5d4486c39068c9fa11f7f851d9568eea4dcba130f994ea9b5e97
-# created: 2022-06-12T16:09:31.61859086Z
+  digest: sha256:e7bb19d47c13839fe8c147e50e02e8b6cf5da8edd1af8b82208cd6f66cc2829c
+# created: 2022-07-05T18:31:20.838186805Z

.github/workflows/unittest.yml

@@ -8,7 +8,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python: ['3.6', '3.7', '3.8', '3.9', '3.10']
+        python: ['3.7', '3.8', '3.9', '3.10']
     steps:
     - name: Checkout
       uses: actions/checkout@v3

.kokoro/test-samples-impl.sh

@@ -33,7 +33,7 @@ export PYTHONUNBUFFERED=1
 env | grep KOKORO
 
 # Install nox
-python3.6 -m pip install --upgrade --quiet nox
+python3.9 -m pip install --upgrade --quiet nox
 
 # Use secrets acessor service account to get secrets
 if [[ -f "${KOKORO_GFILE_DIR}/secrets_viewer_service_account.json" ]]; then
@@ -76,7 +76,7 @@ for file in samples/**/requirements.txt; do
     echo "------------------------------------------------------------"
 
     # Use nox to execute the tests for the project.
-    python3.6 -m nox -s "$RUN_TESTS_SESSION"
+    python3.9 -m nox -s "$RUN_TESTS_SESSION"
     EXIT=$?
 
     # If this is a periodic build, send the test log to the FlakyBot.

.repo-metadata.json

@@ -12,5 +12,6 @@
     "api_id": "cloudbilling.googleapis.com",
     "default_version": "v1",
     "codeowner_team": "",
-    "api_shortname": "cloudbilling"
+    "api_shortname": "cloudbilling",
+    "api_description": "allows developers to manage their billing accounts or browse the catalog of SKUs and pricing."
 }

CONTRIBUTING.rst

@@ -22,7 +22,7 @@ In order to add a feature:
   documentation.
 
 - The feature must work fully on the following CPython versions:
-  3.6, 3.7, 3.8, 3.9 and 3.10 on both UNIX and Windows.
+  3.7, 3.8, 3.9 and 3.10 on both UNIX and Windows.
 
 - The feature must not add unnecessary dependencies (where
   "unnecessary" is of course subjective, but new dependencies should
@@ -221,13 +221,11 @@ Supported Python Versions
 
 We support:
 
--  `Python 3.6`_
 -  `Python 3.7`_
 -  `Python 3.8`_
 -  `Python 3.9`_
 -  `Python 3.10`_
 
-.. _Python 3.6: https://docs.python.org/3.6/
 .. _Python 3.7: https://docs.python.org/3.7/
 .. _Python 3.8: https://docs.python.org/3.8/
 .. _Python 3.9: https://docs.python.org/3.9/
@@ -239,7 +237,7 @@ Supported versions can be found in our ``noxfile.py`` `config`_.
 .. _config: https://github.com/googleapis/python-billing/blob/main/noxfile.py
 
 
-We also explicitly decided to support Python 3 beginning with version 3.6.
+We also explicitly decided to support Python 3 beginning with version 3.7.
 Reasons for this include:
 
 -  Encouraging use of newest versions of Python 3

README.rst

@@ -1,16 +1,15 @@
 Python Client for Cloud Billing API
 ===================================
 
-|ga| |pypi| |versions|
+|stable| |pypi| |versions|
 
-`Cloud Billing API`_: Allows developers to manage billing for their Google Cloud Platform
-projects programmatically.
+`Cloud Billing API`_: allows developers to manage their billing accounts or browse the catalog of SKUs and pricing.
 
 - `Client Library Documentation`_
 - `Product Documentation`_
 
-.. |ga| image:: https://img.shields.io/badge/support-GA-gold.svg
-   :target: https://github.com/googleapis/google-cloud-python/blob/main/README.rst#general-availability
+.. |stable| image:: https://img.shields.io/badge/support-stable-gold.svg
+   :target: https://github.com/googleapis/google-cloud-python/blob/main/README.rst#stability-levels
 .. |pypi| image:: https://img.shields.io/pypi/v/google-cloud-billing.svg
    :target: https://pypi.org/project/google-cloud-billing/
 .. |versions| image:: https://img.shields.io/pypi/pyversions/google-cloud-billing.svg
@@ -32,7 +31,7 @@ In order to use this library, you first need to go through the following steps:
 .. _Select or create a Cloud Platform project.: https://console.cloud.google.com/project
 .. _Enable billing for your project.: https://cloud.google.com/billing/docs/how-to/modify-project#enable_billing_for_a_project
 .. _Enable the Cloud Billing API.:  https://cloud.google.com/billing
-.. _Setup Authentication.: https://googleapis.github.io/google-cloud-python/latest/core/auth.html
+.. _Setup Authentication.: https://googleapis.dev/python/google-api-core/latest/auth.html
 
 Installation
 ~~~~~~~~~~~~
@@ -48,6 +47,27 @@ dependencies.
 .. _`virtualenv`: https://virtualenv.pypa.io/en/latest/
 
 
+Code samples and snippets
+~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Code samples and snippets live in the `samples/` folder.
+
+
+Supported Python Versions
+^^^^^^^^^^^^^^^^^^^^^^^^^
+Our client libraries are compatible with all current [active](https://devguide.python.org/devcycle/#in-development-main-branch) and [maintenance](https://devguide.python.org/devcycle/#maintenance-branches) versions of
+Python.
+
+Python >= 3.7
+
+Unsupported Python Versions
+^^^^^^^^^^^^^^^^^^^^^^^^^^^
+Python <= 3.6
+
+If you are using an [end-of-life](https://devguide.python.org/devcycle/#end-of-life-branches)
+version of Python, we recommend that you update as soon as possible to an actively supported version.
+
+
 Mac/Linux
 ^^^^^^^^^
 
@@ -73,7 +93,7 @@ Next Steps
 ~~~~~~~~~~
 
 -  Read the `Client Library Documentation`_ for Cloud Billing API
-   API to see other available methods on the client.
+   to see other available methods on the client.
 -  Read the `Cloud Billing API Product documentation`_ to learn
    more about the product and see How-to Guides.
 -  View this `README`_ to see the full list of Cloud

noxfile.py

@@ -32,7 +32,7 @@
 
 DEFAULT_PYTHON_VERSION = "3.8"
 
-UNIT_TEST_PYTHON_VERSIONS = ["3.6", "3.7", "3.8", "3.9", "3.10"]
+UNIT_TEST_PYTHON_VERSIONS = ["3.7", "3.8", "3.9", "3.10"]
 UNIT_TEST_STANDARD_DEPENDENCIES = [
     "mock",
     "asyncmock",
@@ -332,28 +332,15 @@ def docfx(session):
 def prerelease_deps(session):
     """Run all tests with prerelease versions of dependencies installed."""
 
-    prerel_deps = [
-        "protobuf",
-        "googleapis-common-protos",
-        "google-auth",
-        "grpcio",
-        "grpcio-status",
-        "google-api-core",
-        "proto-plus",
-        # dependencies of google-auth
-        "cryptography",
-        "pyasn1",
-    ]
-
-    for dep in prerel_deps:
-        session.install("--pre", "--no-deps", "--upgrade", dep)
-
-    # Remaining dependencies
-    other_deps = ["requests"]
-    session.install(*other_deps)
-
+    # Install all dependencies
+    session.install("-e", ".[all, tests, tracing]")
     session.install(*UNIT_TEST_STANDARD_DEPENDENCIES)
-    session.install(*SYSTEM_TEST_STANDARD_DEPENDENCIES)
+    system_deps_all = (
+        SYSTEM_TEST_STANDARD_DEPENDENCIES
+        + SYSTEM_TEST_EXTERNAL_DEPENDENCIES
+        + SYSTEM_TEST_EXTRAS
+    )
+    session.install(*system_deps_all)
 
     # Because we test minimum dependency versions on the minimum Python
     # version, the first version we test with in the unit tests sessions has a
@@ -367,19 +354,44 @@ def prerelease_deps(session):
         constraints_text = constraints_file.read()
 
     # Ignore leading whitespace and comment lines.
-    deps = [
+    constraints_deps = [
         match.group(1)
         for match in re.finditer(
             r"^\s*(\S+)(?===\S+)", constraints_text, flags=re.MULTILINE
         )
     ]
 
-    # Don't overwrite prerelease packages.
-    deps = [dep for dep in deps if dep not in prerel_deps]
-    # We use --no-deps to ensure that pre-release versions aren't overwritten
-    # by the version ranges in setup.py.
-    session.install(*deps)
-    session.install("--no-deps", "-e", ".[all]")
+    session.install(*constraints_deps)
+
+    if os.path.exists("samples/snippets/requirements.txt"):
+        session.install("-r", "samples/snippets/requirements.txt")
+
+    if os.path.exists("samples/snippets/requirements-test.txt"):
+        session.install("-r", "samples/snippets/requirements-test.txt")
+
+    prerel_deps = [
+        "protobuf",
+        # dependency of grpc
+        "six",
+        "googleapis-common-protos",
+        "grpcio",
+        "grpcio-status",
+        "google-api-core",
+        "proto-plus",
+        "google-cloud-testutils",
+        # dependencies of google-cloud-testutils"
+        "click",
+    ]
+
+    for dep in prerel_deps:
+        session.install("--pre", "--no-deps", "--upgrade", dep)
+
+    # Remaining dependencies
+    other_deps = [
+        "requests",
+        "google-auth",
+    ]
+    session.install(*other_deps)
 
     # Print out prerelease package versions
     session.run(
@@ -388,5 +400,16 @@ def prerelease_deps(session):
     session.run("python", "-c", "import grpc; print(grpc.__version__)")
 
     session.run("py.test", "tests/unit")
-    session.run("py.test", "tests/system")
-    session.run("py.test", "samples/snippets")
+
+    system_test_path = os.path.join("tests", "system.py")
+    system_test_folder_path = os.path.join("tests", "system")
+
+    # Only run system tests if found.
+    if os.path.exists(system_test_path) or os.path.exists(system_test_folder_path):
+        session.run("py.test", "tests/system")
+
+    snippets_test_path = os.path.join("samples", "snippets")
+
+    # Only run samples tests if found.
+    if os.path.exists(snippets_test_path):
+        session.run("py.test", "samples/snippets")

scripts/readme-gen/templates/install_deps.tmpl.rst

@@ -12,7 +12,7 @@ Install Dependencies
    .. _Python Development Environment Setup Guide:
        https://cloud.google.com/python/setup
 
-#. Create a virtualenv. Samples are compatible with Python 3.6+.
+#. Create a virtualenv. Samples are compatible with Python 3.7+.
 
     .. code-block:: bash
 

setup.py

@@ -53,12 +53,11 @@
         "proto-plus >= 1.15.0, <2.0.0dev",
         "protobuf >= 3.19.0, <4.0.0dev",
     ),
-    python_requires=">=3.6",
+    python_requires=">=3.7",
     classifiers=[
         "Development Status :: 5 - Production/Stable",
         "Intended Audience :: Developers",
         "Operating System :: OS Independent",
-        "Programming Language :: Python :: 3.6",
         "Programming Language :: Python :: 3.7",
         "Programming Language :: Python :: 3.8",
         "Programming Language :: Python :: 3.9",