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Wojciech Lepczyński for AWS Community Builders

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How to save list on S3 using lambda function and boto3

If you want to save a list on Amazon S3 using a Lambda function and Boto3, you can follow these steps:

1 First, you need to create a new Lambda function in the AWS Console. Choose the Python runtime and give it an appropriate name.
2 In the Lambda function code, you will need to import the Boto3 library by adding the following code at the beginning of your function:

import boto3

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3 Next, you need to create a connection to S3 using the Boto3 client. To do this, add the following code to your function:

s3_client = boto3.client('s3', 'eu-central-1')

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4 Now you can use the put_object method to save your list to S3. For example, if your list is called my_list and you want to save it to a bucket named bucket_name and a file named my_list.txt, you can use the following code:

s3_client.put_object(Bucket='bucket_name', Key='my_list.txt', Body=str(my_list))

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5 Finally, save your Lambda function and test it by invoking it. You should now see your list saved to S3 in the specified bucket and file name.

Full code:

import json
import boto3

def lambda_handler(event, context):

    bucket_name = "save-data-from-lambda"
    list001 = ['this', 'is', 'first', 'list']

    s3_client = boto3.client('s3', 'eu-central-1')
    # save to s3
    save_to_s3 = s3_client.put_object(
        Bucket=bucket_name, 
        Key='my_list.txt', 
        Body=str(list001)
    )

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AWS Lambda Function

That's it! You now know how to save a list to S3 using a Lambda function and Boto3.

I also prepared a video in which you will learn more details. You will learn how to save and read files from S3 bucket:

If you are interested, I also encourage you to visit my blog where you will find the code that you can easily copy and adapt to your needs:
https://lepczynski.it/en/aws_en/how-to-read-and-write-a-file-on-s3-using-lambda-function-and-boto3/

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