statefun-examples/statefun-python-k8s-example/main.py

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#  to you under the Apache License, Version 2.0 (the
#  "License"); you may not use this file except in compliance
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#      http://www.apache.org/licenses/LICENSE-2.0
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from messages_pb2 import LoginEvent
from messages_pb2 import SeenCount

from statefun import StatefulFunctions
from statefun import StateSpec
from statefun import RequestReplyHandler
from statefun import kafka_egress_record

functions = StatefulFunctions()


@functions.bind(
    typename="k8s-demo/greeter",
    states=[StateSpec('seen_count')])
def greet(context, message: LoginEvent):
    state = context.state('seen_count').unpack(SeenCount)
    if not state:
        state = SeenCount()
        state.seen = 1
    else:
        state.seen += 1
    context.state('seen_count').pack(state)

    egress_message = kafka_egress_record(topic="seen", key=message.user_name, value=state)
    context.pack_and_send_egress("k8s-demo/greets-egress", egress_message)


handler = RequestReplyHandler(functions)

#
# Serve the endpoint
#

from flask import request
from flask import make_response
from flask import Flask

app = Flask(__name__)


@app.route('/statefun', methods=['POST'])
def handle():
    response_data = handler(request.data)
    response = make_response(response_data)
    response.headers.set('Content-Type', 'application/octet-stream')
    return response


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