An AWS Lambda Based Function to Copy S3 Objects

With this AWS Lambda function, you can copy objects from a source S3 bucket to one or more target S3 buckets as they are added to the source bucket.

Configuration

IAM Role

Create an IAM role with the following policy:

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Sid": "Stmt1430872797000",
            "Effect": "Allow",
            "Action": [
                "s3:GetBucketTagging",
                "s3:GetObject",
                "s3:PutObject"
            ],
            "Resource": [
                "*"
            ]
        },
        {
            "Sid": "Stmt1430872844000",
            "Effect": "Allow",
            "Action": [
                "cloudwatch:*"
            ],
            "Resource": [
                "*"
            ]
        },
        {
            "Sid": "Stmt1430872852000",
            "Effect": "Allow",
            "Action": [
                "logs:*"
            ],
            "Resource": [
                "*"
            ]
        }
    ]
}

S3 Buckets

1. Ensure you have a source and target bucket. They do not need to reside in the same region.
2. Configure your S3 buckets (see below)

Building the Lambda Package

1. Clone this repo

git clone git@github.com:eleven41/aws-lambda-copy-s3-objects.git
cd aws-copy-encrypt-s3-objects

2. Install requirements

npm install async
npm install aws-sdk

3. Zip up the folder using your favourite zipping utility

Lambda Function

1. Create a new Lambda function.
2. Upload the ZIP package to your lambda function.
3. Add an event source to your Lambda function:

• Event Source Type: S3
• Bucket: your source bucket
• Event Type: Object Created

4. Set your Lambda function to execute using the IAM role you created above.

Configuration

Configuration is performed by setting tags on the source bucket.

Tag Name	Required
TargetBucket	Yes

TargetBucket - A space-separated list of buckets to which the objects will be copied. Optionally, the bucket names can contain a @ character followed by a region to indicate that the bucket resides in a different region.

For example: my-target-bucket1 my-target-bucket1@us-west-2 my-target-bucket3@us-east-1

At this point, if you upload a file to your source bucket, the file should be copied to the target bucket(s).