chore: generate python samples templates in owlbot.py (#149)

Generate python samples templates in owlbot.py

owlbot.py

@@ -41,6 +41,7 @@
 # Add templated files
 # ----------------------------------------------------------------------------
 templated_files = common.py_library(cov_level=99, microgenerator=True)
+python.py_samples(skip_readmes=True)
 s.move(
     templated_files, excludes=[".coveragerc"]
 )  # the microgenerator has a good coveragerc file

samples/snippets/noxfile.py

@@ -17,6 +17,7 @@
 import os
 from pathlib import Path
 import sys
+from typing import Callable, Dict, List, Optional
 
 import nox
 
@@ -27,8 +28,9 @@
 # WARNING - WARNING - WARNING - WARNING - WARNING
 # WARNING - WARNING - WARNING - WARNING - WARNING
 
-# Copy `noxfile_config.py` to your directory and modify it instead.
+BLACK_VERSION = "black==19.10b0"
 
+# Copy `noxfile_config.py` to your directory and modify it instead.
 
 # `TEST_CONFIG` dict is a configuration hook that allows users to
 # modify the test configurations. The values here should be in sync
@@ -37,15 +39,22 @@
 
 TEST_CONFIG = {
     # You can opt out from the test for specific Python versions.
-    'ignored_versions': ["2.7"],
+    'ignored_versions': [],
+
+    # Old samples are opted out of enforcing Python type hints
+    # All new samples should feature them
+    'enforce_type_hints': False,
 
     # An envvar key for determining the project id to use. Change it
     # to 'BUILD_SPECIFIC_GCLOUD_PROJECT' if you want to opt in using a
     # build specific Cloud project. You can also use your own string
     # to use your own Cloud project.
     'gcloud_project_env': 'GOOGLE_CLOUD_PROJECT',
     # 'gcloud_project_env': 'BUILD_SPECIFIC_GCLOUD_PROJECT',
-
+    # If you need to use a specific version of pip,
+    # change pip_version_override to the string representation
+    # of the version number, for example, "20.2.4"
+    "pip_version_override": None,
     # A dictionary you want to inject into your test. Don't put any
     # secrets here. These values will override predefined values.
     'envs': {},
@@ -64,7 +73,7 @@
 TEST_CONFIG.update(TEST_CONFIG_OVERRIDE)
 
 
-def get_pytest_env_vars():
+def get_pytest_env_vars() -> Dict[str, str]:
     """Returns a dict for pytest invocation."""
     ret = {}
 
@@ -79,21 +88,21 @@ def get_pytest_env_vars():
 
 
 # DO NOT EDIT - automatically generated.
-# All versions used to tested samples.
-ALL_VERSIONS = ["2.7", "3.6", "3.7", "3.8"]
+# All versions used to test samples.
+ALL_VERSIONS = ["3.6", "3.7", "3.8", "3.9"]
 
 # Any default versions that should be ignored.
 IGNORED_VERSIONS = TEST_CONFIG['ignored_versions']
 
 TESTED_VERSIONS = sorted([v for v in ALL_VERSIONS if v not in IGNORED_VERSIONS])
 
-INSTALL_LIBRARY_FROM_SOURCE = bool(os.environ.get("INSTALL_LIBRARY_FROM_SOURCE", False))
+INSTALL_LIBRARY_FROM_SOURCE = os.environ.get("INSTALL_LIBRARY_FROM_SOURCE", False) in ("True", "true")
 #
 # Style Checks
 #
 
 
-def _determine_local_import_names(start_dir):
+def _determine_local_import_names(start_dir: str) -> List[str]:
     """Determines all import names that should be considered "local".
 
     This is used when running the linter to insure that import order is
@@ -131,8 +140,11 @@ def _determine_local_import_names(start_dir):
 
 
 @nox.session
-def lint(session):
-    session.install("flake8", "flake8-import-order")
+def lint(session: nox.sessions.Session) -> None:
+    if not TEST_CONFIG['enforce_type_hints']:
+        session.install("flake8", "flake8-import-order")
+    else:
+        session.install("flake8", "flake8-import-order", "flake8-annotations")
 
     local_names = _determine_local_import_names(".")
     args = FLAKE8_COMMON_ARGS + [
@@ -141,7 +153,17 @@ def lint(session):
         "."
     ]
     session.run("flake8", *args)
+#
+# Black
+#
+
 
+@nox.session
+def blacken(session: nox.sessions.Session) -> None:
+    session.install(BLACK_VERSION)
+    python_files = [path for path in os.listdir(".") if path.endswith(".py")]
+
+    session.run("black", *python_files)
 
 #
 # Sample Tests
@@ -151,13 +173,22 @@ def lint(session):
 PYTEST_COMMON_ARGS = ["--junitxml=sponge_log.xml"]
 
 
-def _session_tests(session, post_install=None):
+def _session_tests(session: nox.sessions.Session, post_install: Callable = None) -> None:
+    if TEST_CONFIG["pip_version_override"]:
+        pip_version = TEST_CONFIG["pip_version_override"]
+        session.install(f"pip=={pip_version}")
     """Runs py.test for a particular project."""
     if os.path.exists("requirements.txt"):
-        session.install("-r", "requirements.txt")
+        if os.path.exists("constraints.txt"):
+            session.install("-r", "requirements.txt", "-c", "constraints.txt")
+        else:
+            session.install("-r", "requirements.txt")
 
     if os.path.exists("requirements-test.txt"):
-        session.install("-r", "requirements-test.txt")
+        if os.path.exists("constraints-test.txt"):
+            session.install("-r", "requirements-test.txt", "-c", "constraints-test.txt")
+        else:
+            session.install("-r", "requirements-test.txt")
 
     if INSTALL_LIBRARY_FROM_SOURCE:
         session.install("-e", _get_repo_root())
@@ -177,7 +208,7 @@ def _session_tests(session, post_install=None):
 
 
 @nox.session(python=ALL_VERSIONS)
-def py(session):
+def py(session: nox.sessions.Session) -> None:
     """Runs py.test for a sample using the specified version of Python."""
     if session.python in TESTED_VERSIONS:
         _session_tests(session)
@@ -192,7 +223,7 @@ def py(session):
 #
 
 
-def _get_repo_root():
+def _get_repo_root() -> Optional[str]:
     """ 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())
@@ -201,6 +232,11 @@ def _get_repo_root():
             break
         if Path(p / ".git").exists():
             return str(p)
+        # .git is not available in repos cloned via Cloud Build
+        # setup.py is always in the library's root, so use that instead
+        # https://github.com/googleapis/synthtool/issues/792
+        if Path(p / "setup.py").exists():
+            return str(p)
         p = p.parent
     raise Exception("Unable to detect repository root.")
 
@@ -210,7 +246,7 @@ def _get_repo_root():
 
 @nox.session
 @nox.parametrize("path", GENERATED_READMES)
-def readmegen(session, path):
+def readmegen(session: nox.sessions.Session, path: str) -> None:
     """(Re-)generates the readme for a sample."""
     session.install("jinja2", "pyyaml")
     dir_ = os.path.dirname(path)