👀 Views: 331 💬 Answers: 1 📅 Created: 2025-06-08

aws lambda s3 error-handling Python

I keep running into I'm trying to set up an AWS Lambda function that processes images uploaded to an S3 bucket... I've configured the S3 event notifications to trigger the Lambda function on object creation events. However, I keep working with a `NoSuchKey` behavior when the Lambda function attempts to access the image. Here's the relevant part of my Lambda function that processes the event: ```python import json import boto3 s3_client = boto3.client('s3') def lambda_handler(event, context): for record in event['Records']: bucket = record['s3']['bucket']['name'] key = record['s3']['object']['key'] print(f'Bucket: {bucket}, Key: {key}') # Debugging log # Attempt to get the object try: response = s3_client.get_object(Bucket=bucket, Key=key) # Process the image (not shown here) except s3_client.exceptions.NoSuchKey as e: print(f'behavior: {e}') return { 'statusCode': 404, 'body': json.dumps('File not found') } ``` I've verified that the bucket name and key are correct by logging them in the console. The key seems to contain special characters (like spaces) which I have URL-encoded when uploading the image. For example, the uploaded file name is `test image.jpg`, but in the logs, it shows as `test%20image.jpg`. I ensured that the Lambda function has the correct permissions to access the S3 bucket, and the S3 bucket policy allows the Lambda execution role to read objects. What could be causing the `NoSuchKey` behavior? Could it be related to the way the key is formatted, or is there something else I might be missing? I'm coming from a different tech stack and learning Python. How would you solve this?