Error when sending message from lambda to DLQ

Question

I am following this article in order to send from a lambda to a DLQ:

Using dead-letter queues in Amazon SQS — Boto3 documentation

The code is as follows

from datetime import datetime
import json
import os
import boto3
from botocore.vendored import requests

QUEUE_NAME = os.environ['QUEUE_NAME']
MAX_QUEUE_MESSAGES = os.environ['MAX_QUEUE_MESSAGES']
dead_letter_queue_arn = os.environ['DEAD_LETTER_QUEUE_ARN']
sqs = boto3.resource('sqs')
queue_url = os.environ['SQS_QUEUE_URL']

redrive_policy = {
    'deadLetterTargetArn': dead_letter_queue_arn,
    'maxReceiveCount': '10'
}


def lambda_handler(event, context):

    # Receive messages from SQS queue
    queue = sqs.get_queue_by_name(QueueName=QUEUE_NAME)
    response = requests.post("http://httpbin.org/status/500", timeout=10)
    if response.status_code == 500:
        sqs.set_queue_attributes(QueueUrl=queue_url,
                                 Attributes={
                                    'RedrivePolicy': json.dumps(redrive_policy)
                                    }
                                )

I am doing in this way because I need implement exponential backoff, but I cannot even send to DLQ becase this error

[ERROR] AttributeError: 'sqs.ServiceResource' object has no attribute 'set_queue_attributes'
Traceback (most recent call last):
  File "/var/task/lambda_function.py", line 24, in lambda_handler
    sqs.set_queue_attributes(QueueUrl=queue_url,

According to the set_queue_attributes() documentation, the object has the attribute set_queue_attributes.

Answer 1

Well in case anyone has the same problem, there is a difference between client and resource, I suppose the error has the necessary information but with AWS for me was difficult to spot, according to this

https://boto3.amazonaws.com/v1/documentation/api/latest/reference/services/sqs.html#SQS.Client.set_queue_attributes

response = client.set_queue_attributes(
    QueueUrl='string',
    Attributes={
        'string': 'string'
    }
)

You should be using the client

import boto3

client = boto3.client('sqs')

My mistake was I already has something from boto related to sqs

sqs = boto3.resource('sqs')

That is the reason the error [ERROR] AttributeError: 'sqs.ServiceResource' object has no attribute 'set_queue_attributes'

because I need to use client instead resource from sqs