Google Pub/Sub The total bytes in a batch exceed the maximum allowed limit.

What is Google Pub/Sub The total bytes in a batch exceed the maximum allowed limit.

Understanding Google Pub/Sub

Google Pub/Sub is a messaging service designed to provide reliable, many-to-many, asynchronous messaging between applications. It decouples senders and receivers, allowing for flexible, scalable, and reliable message delivery. Pub/Sub is often used for event-driven architectures, data streaming, and real-time analytics.

Identifying the Symptom: INVALID_BATCH_BYTES

When using Google Pub/Sub, you might encounter the error code INVALID_BATCH_BYTES. This error indicates that the total bytes in a batch of messages exceed the maximum allowed limit. This can prevent messages from being published successfully.

Details About the INVALID_BATCH_BYTES Issue

The INVALID_BATCH_BYTES error occurs when the cumulative size of messages in a batch surpasses the limit set by Google Pub/Sub. The maximum batch size is typically 10 MB. Exceeding this limit can lead to failed message publishing attempts, causing disruptions in message flow and processing.

Why Does This Happen?

This issue often arises when large messages are batched together without considering their combined size. Developers might inadvertently exceed the batch size limit by not accounting for the size of each message.

Steps to Fix the INVALID_BATCH_BYTES Issue

Step 1: Analyze Your Message Sizes

First, evaluate the size of individual messages being sent. Ensure that no single message is excessively large. You can use tools or scripts to calculate the size of your messages before batching them.

Step 2: Adjust Batch Sizes

Modify your batching logic to ensure that the total size of messages in a batch does not exceed the 10 MB limit. Consider reducing the number of messages per batch or splitting large messages into smaller parts.

// Example in Pythonfrom google.cloud import pubsub_v1publisher = pubsub_v1.PublisherClient()topic_path = publisher.topic_path('your-project-id', 'your-topic-id')# Adjust batch settingsbatch_settings = pubsub_v1.types.BatchSettings( max_bytes=1024 * 1024 * 5, # 5 MB max_latency=1, # 1 second)publisher = pubsub_v1.PublisherClient(batch_settings=batch_settings)

Step 3: Monitor and Log Message Sizes

Implement logging to monitor the sizes of messages being published. This can help in identifying patterns or specific messages that frequently cause the issue.

Step 4: Use Compression

If your messages are text-heavy, consider compressing them before publishing. This can significantly reduce the size of each message, allowing more messages to fit within the batch size limit.

Additional Resources

For more information on managing batch sizes and optimizing message publishing, refer to the following resources:

Google Cloud Pub/Sub Publisher Guide Google Cloud Pub/Sub Best Practices