S3 Export Connector

The S3 export connector writes processed events to an S3 bucket in NDJSON (newline-delimited JSON) format.

Configuration

{
  "name": "Data Warehouse Export",
  "type": "s3-export",
  "config": {
    "bucket": "my-data-lake",
    "prefix": "uniflow/events/",
    "region": "us-east-1"
  }
}

Field	Type	Description
bucket	string	Target S3 bucket name
prefix	string	Key prefix for exported files
region	string	Bucket region

Output format

Events are written as NDJSON files, one event per line:

s3://my-data-lake/uniflow/events/2025/03/08/events-001.ndjson

Each line is a complete JSON object:

{"type":"track","event":"Purchase","userId":"user_123","properties":{"revenue":99.99},"timestamp":"2025-03-08T12:00:00.000Z"}
{"type":"identify","userId":"user_123","traits":{"name":"Jane Doe"},"timestamp":"2025-03-08T12:01:00.000Z"}

IAM permissions

The Uniflow stack’s Lambda execution role needs s3:PutObject permission on your target bucket. For cross-account buckets, add a bucket policy:

{
  "Statement": [{
    "Effect": "Allow",
    "Principal": { "AWS": "arn:aws:iam::UNIFLOW_ACCOUNT:role/..." },
    "Action": "s3:PutObject",
    "Resource": "arn:aws:s3:::my-data-lake/uniflow/*"
  }]
}