Processing messages in a sqs with lambda function. The failed messages are collected into a dead letter queue.

1. Processing SQS with
Lambda
Processing SQS messages with Lambda and sending the failed messages to Dead Letter Queue
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2. About the project
This is a series of my personal
projects which I took to prepare
for my AWS certification.
In this project I first created a
SQS and a lambda function to
process the messages sent to
the SQS.
The messages that gets failed to
get processed will be sent to a
dead letter queue.
The entire stack will be created
using CloudFormation,
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Dead letter queue
message
Message producer
Amazon Simple Queue
Service (Amazon SQS)
AWS Lambda
Failed message
Trigger a lambda function
AWS Cloud

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Create the entire stack using CloudFormation
The stack consists of:
1. Main SQS
2. Dead Letter Queue
3. Lambda

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CloudFormation .yaml template
The CFT can be downloaded from
https://github.com/subhamaybhattacharyya/awsprojects/blob/main/1-sqs-dlq-lambda-stack.yaml

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The main SQS - my-demo-queue

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The Dead Letter Queue - my-demo-dead-letter-queue

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The Lambda function - my-lambda-with-dlq

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The Lambda Execution Role - MyLambdaExecutionRole
Basic Execution Policy for creating log group and log stream
Policy for receiving and sending SQS message and
GetQueueAttributes

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The Lambda Event Mapping

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Now we will send a message to the SQS.

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Check the CloudWatch log to see the message been processed

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Now I will remove the policies from the execution role to fail the lambda execution

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Now we will send another message to the queue
The message was not processed and
when the receive count exceeds
maximum receive count the message
gets pushed to dead letter queue.
>

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Message is collected into the dead letter queue.

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Now we will delete the stack to clean up the resources.