Aws DynamoDb Stream for NextShardIterator key in response

Question

i am using dynamodbstream calling with method response = client.get_records(ShardIterator=shard_iterator, Limit=1)

initially response contain response['NextShardIterator'] key

but after some time I got KeyError: 'NextShardIterator' why it is absent in response

Answer 1

Instead of writing code like the following:

shard_iterator = response['NextShardIterator']

if not shard_iterator:
    break

Write the following instead:

if 'NextShardIterator' in response:
    shard_iterator = response['NextShardIterator']
else:
    break

Or you can use dict.get with a default value, as follows:

shard_iterator = response.get('NextShardIterator', None)

if not shard_iterator:
    break