example_gce_backend.py

# Copyright 2017 Google Inc. All Rights Reserved.
#
# 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.

import platform

import flask

import validate_jwt

CLOUD_PROJECT_ID = "YOUR_PROJECT_ID"
BACKEND_SERVICE_ID = "YOUR_BACKEND_SERVICE_ID"

app = flask.Flask(__name__)


@app.route("/")
def root():
    jwt = flask.request.headers.get("x-goog-iap-jwt-assertion")
    if jwt is None:
        return "Unauthorized request."
    expected_audience = (
        f"/projects/{CLOUD_PROJECT_ID}/global/backendServices/{BACKEND_SERVICE_ID}"
    )
    user_id, user_email, error_str = validate_jwt.validate_iap_jwt(
        jwt, expected_audience
    )
    if error_str:
        return f"Error: {error_str}"
    else:
        return f"Hi, {user_email}. I am {platform.node()}."


if __name__ == "__main__":
    app.run()