AWS Kinesis ExpiredIteratorException

What is AWS Kinesis ExpiredIteratorException

Understanding AWS Kinesis

AWS Kinesis is a powerful service designed to handle real-time data streaming at scale. It allows developers to collect, process, and analyze streaming data in real-time, enabling timely insights and actions. Kinesis is often used for applications such as log and event data collection, real-time analytics, and more.

Identifying the Symptom: ExpiredIteratorException

When working with AWS Kinesis, you might encounter the ExpiredIteratorException. This error typically manifests when attempting to read data from a Kinesis stream using an iterator that has expired. The iterator is a crucial component for accessing data records within a shard.

Exploring the Issue: What Causes ExpiredIteratorException?

The ExpiredIteratorException occurs when the shard iterator you are using has expired. In AWS Kinesis, shard iterators are valid for a limited time, typically 5 minutes. If you attempt to use an iterator beyond this time frame, the system will throw this exception.

For more information on shard iterators, you can refer to the AWS Kinesis GetShardIterator API documentation.

Steps to Resolve ExpiredIteratorException

Step 1: Obtain a New Shard Iterator

To resolve this issue, you need to obtain a new shard iterator. You can do this by calling the GetShardIterator API. Ensure that you specify the correct parameters, such as the stream name, shard ID, and shard iterator type.

aws kinesis get-shard-iterator \ --stream-name YourStreamName \ --shard-id ShardId-000000000000 \ --shard-iterator-type LATEST

Step 2: Use the New Iterator Promptly

Once you have obtained a new shard iterator, use it promptly to read records from the shard. Remember that the iterator is time-sensitive, so avoid unnecessary delays in processing.

Step 3: Implement Iterator Renewal Logic

To prevent future occurrences of this exception, consider implementing logic in your application to renew the shard iterator before it expires. This can be done by periodically obtaining a new iterator as you process records.

Additional Resources

For further reading on handling shard iterators and managing Kinesis streams, check out the following resources:

AWS Kinesis Developer Guide AWS Kinesis Data Streams