'''
This script is used to redrive message in (src) queue to (tgt) queue
The solution is to set the Target Queue as the Source Queue's Dead Letter Queue.
Also set Source Queue's redrive policy, Maximum Receives to 1.
Also set Source Queue's VisibilityTimeout to 5 seconds (a small period)
Then read data from the Source Queue.
Source Queue's Redrive Policy will copy the message to the Target Queue.
'''
import argparse
import json
import boto3
sqs = boto3.client('sqs')
def parse_args():
parser = argparse.ArgumentParser()
parser.add_argument('-s', '--src', required=True,
help='Name of source SQS')
parser.add_argument('-t', '--tgt', required=True,
help='Name of targeted SQS')
args = parser.parse_args()
return args
def verify_queue(queue_name):
queue_url = sqs.get_queue_url(QueueName=queue_name)
return True if queue_url.get('QueueUrl') else False
def get_queue_attribute(queue_url):
queue_attributes = sqs.get_queue_attributes(
QueueUrl=queue_url,
AttributeNames=['All'])['Attributes']
print(queue_attributes)
return queue_attributes
def main():
args = parse_args()
for q in [args.src, args.tgt]:
if not verify_queue(q):
print(f"Cannot find {q} in AWS SQS")
src_queue_url = sqs.get_queue_url(QueueName=args.src)['QueueUrl']
target_queue_url = sqs.get_queue_url(QueueName=args.tgt)['QueueUrl']
target_queue_attributes = get_queue_attribute(target_queue_url)
# Set the Source Queue's Redrive policy
redrive_policy = {
'deadLetterTargetArn': target_queue_attributes['QueueArn'],
'maxReceiveCount': '1'
}
sqs.set_queue_attributes(
QueueUrl=src_queue_url,
Attributes={
'VisibilityTimeout': '5',
'RedrivePolicy': json.dumps(redrive_policy)
}
)
get_queue_attribute(src_queue_url)
# read all messages
num_received = 0
while True:
try:
resp = sqs.receive_message(
QueueUrl=src_queue_url,
MaxNumberOfMessages=10,
AttributeNames=['All'],
WaitTimeSeconds=5)
num_message = len(resp.get('Messages', []))
if not num_message:
break
num_received += num_message
except Exception:
break
print(f"Redrive {num_received} messages")
# Reset the Source Queue's Redrive policy
sqs.set_queue_attributes(
QueueUrl=src_queue_url,
Attributes={
'VisibilityTimeout': '30',
'RedrivePolicy': ''
}
)
get_queue_attribute(src_queue_url)
if __name__ == "__main__":
main()