├── .gitignore ├── CONTRIBUTING.md ├── LICENSE ├── Makefile ├── README.md ├── gcloud_flask_oauth_cors ├── __init__.py └── auth.py ├── requirements.txt └── setup.py /.gitignore: -------------------------------------------------------------------------------- 1 | *~ 2 | __pycache__ 3 | test-results 4 | build 5 | dist 6 | -------------------------------------------------------------------------------- /CONTRIBUTING.md: -------------------------------------------------------------------------------- 1 | # How to Contribute 2 | 3 | We'd love to accept your patches and contributions to this project. There are 4 | just a few small guidelines you need to follow. 5 | 6 | ## Contributor License Agreement 7 | 8 | Contributions to this project must be accompanied by a Contributor License 9 | Agreement. You (or your employer) retain the copyright to your contribution; 10 | this simply gives us permission to use and redistribute your contributions as 11 | part of the project. 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We also recommend that a 186 | file or class name and description of purpose be included on the 187 | same "printed page" as the copyright notice for easier 188 | identification within third-party archives. 189 | 190 | Copyright [yyyy] [name of copyright owner] 191 | 192 | Licensed under the Apache License, Version 2.0 (the "License"); 193 | you may not use this file except in compliance with the License. 194 | You may obtain a copy of the License at 195 | 196 | http://www.apache.org/licenses/LICENSE-2.0 197 | 198 | Unless required by applicable law or agreed to in writing, software 199 | distributed under the License is distributed on an "AS IS" BASIS, 200 | WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 201 | See the License for the specific language governing permissions and 202 | limitations under the License. 203 | -------------------------------------------------------------------------------- /Makefile: -------------------------------------------------------------------------------- 1 | init: 2 | python3 -m pip install --user -r requirements.txt 3 | 4 | package: 5 | python3 setup.py sdist bdist_wheel 6 | python3 -m twine upload dist/* 7 | 8 | docs: 9 | cd docs && sphinx-build -M html . . 10 | 11 | .PHONY: init package docs 12 | -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | # Flask OAuth CORS [![PyPI version](https://badge.fury.io/py/gcloud-flask-oauth-cors.svg)](https://badge.fury.io/py/gcloud-flask-oauth-cors) 2 | 3 | > A small class that helps with authentication and CORS for HTTP-triggered cloud functions written in Python and hosted on GCP. 4 | 5 | _Please note: This is not an officially supported Google product._ 6 | 7 | If you are using OAuth to authenticate to a [Cloud Function written in Python](https://cloud.google.com/functions/docs/concepts/python-runtime) and hosted on GCP, and your client is running in a browser, this is for you. If not, you probably won't find this useful. 8 | 9 | ## Features 10 | 11 | * Responds correctly and configurably to the HTTP OPTIONS method used by browsers to do pre-flight checks as part of CORS 12 | * Retrieves an OAuth2 token supplied in the `Authorization` HTTP header, validates it, and then fetches the information encoded by the token 13 | * Gives you back either a valid token, or a response to send back to the user in case a valid token can't be found 14 | 15 | ## Installation 16 | 17 | Install using pip: 18 | 19 | ```sh 20 | python3 -m pip install --user gcloud-flask-oauth-cors 21 | ``` 22 | 23 | ## Usage 24 | 25 | To use this package: 26 | 27 | - [Create an OAuth client ID](https://developers.google.com/identity/protocols/OAuth2WebServer). 28 | - [Pass the OAuth client ID as an environment variable](https://cloud.google.com/functions/docs/env-var) to your cloud function. 29 | 30 | Then, you can use the following: 31 | 32 | ```py 33 | import gcloud_flask_oauth_cors as oauth 34 | 35 | def my_function_name(request): 36 | auth = oauth.Auth(os.getenv("OAUTH_CLIENT_ID")) 37 | id_info = auth.get_id_info(request) 38 | if id_info is None: 39 | # If we were called with the HTTP OPTIONS method, this will return the relevant CORS headers. 40 | # If another HTTP method was used and we can't authenticate, this will return a 401 (Unauthorized) 41 | return auth.get_response() 42 | 43 | # Do something with the id_info, for example: 44 | print(id_info["sub"]) 45 | ``` 46 | 47 | On the client side, you can use [Google Sign-in](https://developers.google.com/identity/sign-in/web/). Make sure you pass your `id_token` in any requests like this: 48 | 49 | ```js 50 | let xhr = new XMLHttpRequest(); 51 | xhr.setRequestHeader('Authorization', `Bearer ${id_token}`); 52 | ``` 53 | -------------------------------------------------------------------------------- /gcloud_flask_oauth_cors/__init__.py: -------------------------------------------------------------------------------- 1 | #!/usr/bin/python3 2 | # 3 | # Copyright 2019 Google LLC 4 | # 5 | # Licensed under the Apache License, Version 2.0 (the "License"); 6 | # you may not use this file except in compliance with the License. 7 | # You may obtain a copy of the License at 8 | # 9 | # https://www.apache.org/licenses/LICENSE-2.0 10 | # 11 | # Unless required by applicable law or agreed to in writing, software 12 | # distributed under the License is distributed on an "AS IS" BASIS, 13 | # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 | # See the License for the specific language governing permissions and 15 | # limitations under the License. 16 | 17 | name = "gcloud_flask_oauth_cors" 18 | from .auth import Auth -------------------------------------------------------------------------------- /gcloud_flask_oauth_cors/auth.py: -------------------------------------------------------------------------------- 1 | #!/usr/bin/python3 2 | # 3 | # Copyright 2019 Google LLC 4 | # 5 | # Licensed under the Apache License, Version 2.0 (the "License"); 6 | # you may not use this file except in compliance with the License. 7 | # You may obtain a copy of the License at 8 | # 9 | # https://www.apache.org/licenses/LICENSE-2.0 10 | # 11 | # Unless required by applicable law or agreed to in writing, software 12 | # distributed under the License is distributed on an "AS IS" BASIS, 13 | # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 | # See the License for the specific language governing permissions and 15 | # limitations under the License. 16 | 17 | from google.oauth2 import id_token 18 | from google.auth.transport import requests 19 | 20 | class Auth: 21 | def __init__(self, oauth_client_id, cors_allow_origin = "*", cors_allow_methods = "*", cors_allow_headers = "*", cors_max_age = "*"): 22 | self.__oauth_client_id = oauth_client_id 23 | self.__cors_allow_origin = cors_allow_origin 24 | self.__cors_allow_methods = cors_allow_methods 25 | self.__cors_allow_headers = cors_allow_headers 26 | self.__cors_max_age = cors_max_age 27 | 28 | def get_id_info(self, request): 29 | # Set CORS headers for the preflight request 30 | if request.method == 'OPTIONS': 31 | # Allows GET requests from any origin with the Content-Type 32 | # header and caches preflight response for an 3600s 33 | headers = { 34 | 'Access-Control-Allow-Origin': self.__cors_allow_origin, 35 | 'Access-Control-Allow-Methods': self.__cors_allow_methods, 36 | 'Access-Control-Allow-Headers': self.__cors_allow_headers, 37 | 'Access-Control-Max-Age': self.__cors_max_age, 38 | 'Access-Control-Allow-Credentials': 'true' 39 | } 40 | self.__response = ('', 204, headers) 41 | return None 42 | 43 | token = request.headers['Authorization'].split(' ').pop() 44 | auth_request = requests.Request() 45 | id_info = id_token.verify_oauth2_token(token, auth_request, self.__oauth_client_id) 46 | if not id_info: 47 | self.__response = ('Unauthorized', 401, headers) 48 | return None 49 | return id_info 50 | 51 | def get_response(self): 52 | return self.__response 53 | -------------------------------------------------------------------------------- /requirements.txt: -------------------------------------------------------------------------------- 1 | setuptools 2 | wheel 3 | twine 4 | google-auth 5 | google-api-python-client 6 | -------------------------------------------------------------------------------- /setup.py: -------------------------------------------------------------------------------- 1 | #!/usr/bin/python3 2 | # 3 | # Copyright 2019 Google LLC 4 | # 5 | # Licensed under the Apache License, Version 2.0 (the "License"); 6 | # you may not use this file except in compliance with the License. 7 | # You may obtain a copy of the License at 8 | # 9 | # https://www.apache.org/licenses/LICENSE-2.0 10 | # 11 | # Unless required by applicable law or agreed to in writing, software 12 | # distributed under the License is distributed on an "AS IS" BASIS, 13 | # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 | # See the License for the specific language governing permissions and 15 | # limitations under the License. 16 | 17 | import setuptools 18 | 19 | with open("README.md", "r") as fh: 20 | long_description = fh.read() 21 | 22 | setuptools.setup( 23 | name="gcloud-flask-oauth-cors", 24 | version="0.1.1", 25 | author="Jez Humble", 26 | author_email="humble@google.com", 27 | description="A tiny utility to authenticate requests using GCP OAuth and send CORS headers in Flask", 28 | long_description=long_description, 29 | long_description_content_type="text/markdown", 30 | url="https://github.com/googlecloudplatform/flask-oauth-cors", 31 | install_requires=[ 32 | "google-api-python-client", 33 | "google-auth" 34 | ], 35 | packages=setuptools.find_packages(), 36 | classifiers=[ 37 | "Programming Language :: Python :: 3", 38 | "License :: OSI Approved :: Apache Software License", 39 | "Operating System :: OS Independent", 40 | ], 41 | ) 42 | --------------------------------------------------------------------------------