Posted on Jun 17, 2024

☁️ AWS - Email notification system

Technologies:

☁️ AWS: 🪣 S3 bucket, ⚡️ lambda function, 🔔 SNS, 📬 SQS
🤖 IaC: 🏗️ Terraform
🔄 CD: 🛠️ GitLab

Project resume: Email notification system developed in AWS. Once a file is uploaded to an s3 bucket it triggers an event which calls a lambda function and notifies service subscribers that a file has been uploaded.

📌Requirements

🎯Workflow

1️⃣ Source code 📄
2️⃣ Lambda function ⚡️
3️⃣ Deploy to AWS through GitLab 🚀

1️⃣ Source code 📄

Gitlab project

Structure

terraform └── terraform ├── bucket │ ├── main.tf │ └── output.tf │ └── variables.tf ├── lambda │ ├── main.tf │ └── output.tf │ └── variables.tf │ └── lambda_assume_role_policy.json │ └── lambda_policy.json │ └── lambda_function.py │ └── lambda_function.zip ├── sns │ ├── main.tf │ └── output.tf │ └── variables.tf ├── sqs │ ├── main.tf │ └── output.tf │ └── variables.tf ├── main.tf └── providers.tf

It is organized into modules dedicated to different AWS services, each designed to serve a specific purpose and facilitate the management and scalability of the cloud environment.In addition, using Terraform to orchestrate these modules ensures a consistent and controlled deployment of the infrastructure, aligned with best practices for configuration management and agile development in the cloud.

2️⃣ Lambda function ⚡️

import json import boto3 # Initialize AWS clients s3_client = boto3.client('s3') sns_client = boto3.client('sns') sqs_client = boto3.client('sqs') def lambda_handler(event, context): # Define SNS topic ARN and SQS queue URL  sns_topic_arn = 'arn:aws:sns:us-east-2:087243254862:notifcationsystem-bucket' sqs_queue_url = 'https://sqs.us-east-2.amazonaws.com/087243254862/notification' # Process S3 event records  for record in event['Records']: # Print the entire event for debugging purposes  print(event) # Extract S3 bucket and object information from the event record  s3_bucket = record['s3']['bucket']['name'] s3_key = record['s3']['object']['key'] # Example: Prepare metadata to send to SQS  metadata = { 'bucket': s3_bucket, 'key': s3_key, 'timestamp': record['eventTime'] } # Send metadata to SQS queue  sqs_response = sqs_client.send_message( QueueUrl=sqs_queue_url, MessageBody=json.dumps(metadata) ) # Example: Prepare notification message to send to SNS  notification_message = f"New file uploaded to S3 bucket '{s3_bucket}' with key '{s3_key}'" # Publish notification message to SNS topic  sns_response = sns_client.publish( TopicArn=sns_topic_arn, Message=notification_message, Subject="File Upload Notification" ) # Return a success response  return { 'statusCode': 200, 'body': json.dumps('Processing complete') }