This Python example shows you how to enable long polling in Amazon SQS in one of these ways:
Long polling reduces the number of empty responses by allowing Amazon SQS to wait a specified time for a message to become available in the queue before sending a response. Also, long polling eliminates false empty responses by querying all of the servers instead of a sampling of servers. To enable long polling, you must specify a non-zero wait time for received messages. You can do this by setting the ReceiveMessageWaitTimeSeconds parameter of a queue or by setting the WaitTimeSeconds parameter on a message when it is received.
In these examples, the AWS SDK for Python is used to enable long polling using the following Amazon SQS methods.
For more information, see Amazon SQS Long Polling in the Amazon Simple Queue Service Developer Guide.
The example below shows how to:
import boto3
# Create SQS client
sqs = boto3.client('sqs')
# Create a SQS queue with long polling enabled
response = sqs.create_queue(
QueueName='SQS_QUEUE_NAME',
Attributes={'ReceiveMessageWaitTimeSeconds': '20'}
)
print(response['QueueUrl'])
The example below shows how to:
import boto3
# Create SQS client
sqs = boto3.client('sqs')
queue_url = 'SQS_QUEUE_URL'
# Enable long polling on an existing SQS queue
sqs.set_queue_attributes(
QueueUrl=queue_url,
Attributes={'ReceiveMessageWaitTimeSeconds': '20'}
)
The example below shows how to:
import boto3
# Create SQS client
sqs = boto3.client('sqs')
queue_url = 'SQS_QUEUE_URL'
# Long poll for message on provided SQS queue
response = sqs.receive_message(
QueueUrl=queue_url,
AttributeNames=[
'SentTimestamp'
],
MaxNumberOfMessages=1,
MessageAttributeNames=[
'All'
],
WaitTimeSeconds=20
)
print(response)