Files are empty after copying it to the S3 bucket

I have an S3 bucket called source-bucket-6 and I write a lambda function to copy files from the lambda location to the S3 bucket.

As you see in the screenshot, here we have two files Index.html and Test.txt. I just want to copy those files to the S3 bucket. But whenever I try to copy them to the bucket, I see both files are empty and there's no content in the files. Here's my lambda code:

import boto3
import os

s3 = boto3.client('s3')
cwd = os.getcwd()


def lambda_handler(event, context):
    bucket = 'source-bucket-6'


    files = [f for f in os.listdir('.') if os.path.isfile(f)]
    for f in files:
        if f != "lambda_function.py":
            s3.put_object(Bucket=bucket, Key=f)
            print(f"------------------{f} ")
        
    print("Put Completed")

Your put_object command is not specifying any content for the object.

If you want to upload a file, use:

s3.upload_file(Filename=f, Bucket=bucket, Key=f)

where f is the filename of the file to upload.

You are missing Body argument. It should be:

s3.put_object(Bucket=bucket, Key=f, Body=open(f, 'r'))