cnn-classification-service/cnn_classification_service/main.py

#!/usr/bin/env python3
import time

import jaeger_client
import opentracing

import logging
import os
import sys
import pika
import json

from sentry_sdk.integrations.logging import LoggingIntegration
import sentry_sdk

from config import Config

from magic_doer import MagicDoer


def message_callback(channel, method, properties, body):
    with opentracing.tracer.start_active_span('messageHandling', finish_on_close=True) as span:
        try:
            msg = json.loads(body.decode('utf-8'))
        except (UnicodeDecodeError, json.JSONDecodeError) as e:
            logging.warning(f"Invalid message recieved: {e}")
            return

        span.log_kv({'event': 'messageParsed', 'sampleTag': msg['tag']})

        with opentracing.tracer.start_active_span('runAlgorithm', child_of=span) as child_span:
            results = MagicDoer.run_everything(msg)  # <- This is where the magic happens

        if results:
            channel.basic_publish(
                exchange=Config.PIKA_OUTPUT_EXCHANGE,
                routing_key='classification-result',
                body=json.dumps(results).encode("utf-8")
            )
            channel.basic_ack(delivery_tag=method.delivery_tag)


def main():
    # setup logging

    logging.basicConfig(
        stream=sys.stdout,
        format="%(asctime)s - %(name)s [%(levelname)s]: %(message)s",
        level=Config.LOG_LEVEL
    )

    # setup observability stuffs

    if Config.SENTRY_DSN:
        sentry_logging = LoggingIntegration(
            level=logging.DEBUG,  # Capture info and above as breadcrumbs
            event_level=logging.ERROR  # Send errors as events
        )
        sentry_sdk.init(
            dsn=Config.SENTRY_DSN,
            integrations=[sentry_logging],
            traces_sample_rate=1.0,
            send_default_pii=True,
            release=Config.RELEASE_ID,
            environment=Config.RELEASEMODE,
            _experiments={"auto_enabling_integrations": True}
        )

    jaeger_client.Config(config={}, service_name='cnn-classification-service', validate=True).initialize_tracer()

    # Start the memes

    logging.info("Connecting to MQ service...")
    connection = pika.BlockingConnection(pika.connection.URLParameters(Config.PIKA_URL))
    channel = connection.channel()
    channel.exchange_declare(exchange=Config.PIKA_INPUT_EXCHANGE, exchange_type='direct')

    queue_declare_result = channel.queue_declare(queue='cnnqueue', exclusive=False)
    queue_name = queue_declare_result.method.queue

    channel.queue_bind(exchange=Config.PIKA_INPUT_EXCHANGE, routing_key='feature', queue=queue_name)

    channel.basic_qos(prefetch_count=1)

    channel.basic_consume(queue=queue_name, on_message_callback=message_callback, auto_ack=False)

    logging.info("Connection complete! Listening to messages...")
    try:
        channel.start_consuming()
    except KeyboardInterrupt:
        logging.info("SIGINT Received! Stopping stuff...")
        channel.stop_consuming()

    time.sleep(2)  # lol
    opentracing.tracer.close()


if __name__ == '__main__':
    main()