GCP Pub/Sub Subscription Acknowledgment Timing Issues Causing Message Redelivery
I tried several approaches but none seem to work. I've been researching this but I'm having trouble with message acknowledgments in my Google Cloud Pub/Sub implementation. My service is set up to process messages using the `google-cloud-pubsub` library in Python. I've noticed that some messages are being redelivered even after successfully processing them, which is causing duplicate entries in my database. I currently have a subscription configured with the default acknowledgment deadline of 10 seconds. However, some messages take longer to process because they require additional API calls. I tried increasing the acknowledgment deadline to 30 seconds, but I'm still observing redelivery in certain scenarios, especially during peak loads. Here’s a simplified version of my processing code: ```python from google.cloud import pubsub_v1 import time def callback(message): print(f'Received message: {message.data}') time.sleep(15) # Simulate processing time message.ack() subscriber = pubsub_v1.SubscriberClient() subscription_path = subscriber.subscription_path('my-project', 'my-subscription') streaming_pull_future = subscriber.subscribe(subscription_path, callback=callback) print(f'Listening for messages on {subscription_path}... ') ``` I also tried using the `message.nack()` method in case of processing failures, but it seems like the messages are acknowledged sometimes before the function has finished its work. Is there a best practice for managing acknowledgment in this scenario, especially when dealing with longer processing times? Should I also consider implementing a manual acknowledgment strategy? Any insights would be appreciated! For context: I'm using Python on Linux. Any help would be greatly appreciated! I'm working in a Ubuntu 22.04 environment. This is happening in both development and production on CentOS. What's the best practice here?