Cloud Run events samples should use sdk-python cloudevents

[cumason123]

In which file did you encounter the issue?

events-pubsub and events-storage

Describe the issue

These repo's are showing how to handle cloudevent wrapped HTTP requests in python. There exists a python library: sdk-python cloudevents which recently reached version 1.2.0 that handles this exact purpose.

e.g.:

Instead of

from flask import Flask, request


required_fields = ['Ce-Id', 'Ce-Source', 'Ce-Type', 'Ce-Specversion']
app = Flask(__name__)


@app.route('/', methods=['POST'])
def index():
    for field in required_fields:
        if field not in request.headers:
            errmsg = f'Bad Request: missing required header {field}'
            print(errmsg)
            return errmsg, 400

we could do this:

import cloudevents.exceptions as cloud_exceptions
from cloudevents.http import from_http

from flask import Flask, request


app = Flask(__name__)

@app.route('/', methods=['POST'])
def index():
    # Create CloudEvent from HTTP headers and body
    try:
        event = from_http(request.headers, request.get_data())

    except cloud_exceptions.MissingRequiredFields as e:
        print(f"cloudevents.exceptions.MissingRequiredFields: {e}")
        return "Failed to find all required cloudevent fields. ", 400