[2021] Download S3 File — Lambda

If the file is small (e.g., a JSON config or a small CSV), you don't need to write it to disk at all. You can read the file content directly into a variable.

AWS Lambda provides a writable ephemeral storage space located at /tmp . This is the best approach if you need to pass the file to an external library (like pandas or an image processor) that requires a file path. lambda download s3 file

import boto3 def lambda_handler(event, context): s3 = boto3.client('s3') response = s3.get_object(Bucket='my-cool-bucket', Key='config.json') file_content = response['Body'].read().decode('utf-8') print("File Content Loaded Successfully") return file_content Use code with caution. Key Considerations for Production 1. Memory Limits If the file is small (e