From a2cbc3245460e1ae1d310de6a2a4007d5a3a06b7 Mon Sep 17 00:00:00 2001
From: Bu Sun Kim <8822365+busunkim96@users.noreply.github.com>
Date: Tue, 16 Mar 2021 14:56:02 -0600
Subject: [PATCH] feat: expose library version at `google.auth.__version`
 (#683)

Move the version from `setup.py` to `google/auth/version.py`.  Same as https://github.com/googleapis/python-api-core/pull/80.  (see https://github.com/googleapis/python-api-core/issues/27 for motivation). This is option 3 in https://packaging.python.org/guides/single-sourcing-package-version/.

This unblocks a version check I'd like to add in https://github.com/googleapis/python-api-core/pull/134.

Usage:

```py
>>> import google.auth
>>> google.auth.__version__
'1.25.0'
```
---
 google/auth/__init__.py |  5 +++++
 google/auth/version.py  | 15 +++++++++++++++
 setup.py                |  8 +++++++-
 3 files changed, 27 insertions(+), 1 deletion(-)
 create mode 100644 google/auth/version.py

diff --git a/google/auth/__init__.py b/google/auth/__init__.py
index 22d61c66f..861abe7ea 100644
--- a/google/auth/__init__.py
+++ b/google/auth/__init__.py
@@ -16,8 +16,13 @@
 
 import logging
 
+from google.auth import version as google_auth_version
 from google.auth._default import default, load_credentials_from_file
 
+
+__version__ = google_auth_version.__version__
+
+
 __all__ = ["default", "load_credentials_from_file"]
 
 # Set default logging handler to avoid "No handler found" warnings.
diff --git a/google/auth/version.py b/google/auth/version.py
new file mode 100644
index 000000000..54ad93268
--- /dev/null
+++ b/google/auth/version.py
@@ -0,0 +1,15 @@
+# Copyright 2021 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.
+
+__version__ = "1.27.1"
diff --git a/setup.py b/setup.py
index 33089cb71..16ba98cfd 100644
--- a/setup.py
+++ b/setup.py
@@ -13,6 +13,7 @@
 # limitations under the License.
 
 import io
+import os
 
 from setuptools import find_packages
 from setuptools import setup
@@ -37,7 +38,12 @@
 with io.open("README.rst", "r") as fh:
     long_description = fh.read()
 
-version = "1.27.1"
+package_root = os.path.abspath(os.path.dirname(__file__))
+
+version = {}
+with open(os.path.join(package_root, "google/auth/version.py")) as fp:
+    exec(fp.read(), version)
+version = version["__version__"]
 
 setup(
     name="google-auth",