text: # 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.
  """Google Cloud Endpoints sample application.
  
  Demonstrates how to create a simple API.
  """
  
  import base64
  import json
  import logging
  
  from flask import Flask, jsonify, request
  from six.moves import http_client
  
  app = Flask(__name__)
  
  
  def _base64_decode(encoded_str):
      # Add paddings manually if necessary.
      num_missed_paddings = 4 - len(encoded_str) % 4
      if num_missed_paddings != 4:
          encoded_str += b'=' * num_missed_paddings
      return base64.b64decode(encoded_str).decode('utf-8')
  
  
  @app.route('/processmessage', methods=['POST'])
  def process():
      """Process messages with information about S3 objects"""
      message = request.get_json().get('inputMessage', '')
      # add other processing as needed
      # for example, add event to PubSub topic or
      # download object using presigned URL, save in Cloud Storage, invoke ML APIs
      return jsonify({'In app code for endpoint, received message': message})
  
  
  @app.errorhandler(http_client.INTERNAL_SERVER_ERROR)
  def unexpected_error(e):
      """Handle exceptions by returning swagger-compliant json."""
      logging.exception('An error occured while processing the request.')
      response = jsonify({
          'code': http_client.INTERNAL_SERVER_ERROR,
          'message': 'Exception: {}'.format(e)
      })
      response.status_code = http_client.INTERNAL_SERVER_ERROR
      return response
  
  
  if __name__ == '__main__':
      # This is used when running locally. Gunicorn is used to run the
      # application on Google App Engine. See entrypoint in app.yaml.
      app.run(host='127.0.0.1', port=8080, debug=True)
  