An S3 snapshot exposure source lets you upload exposure data in batch by delivering gzip-compressed CSV files to an MX8 Labs-managed S3 bucket. This is the right choice when you collect exposure data in your own systems and want to send it server-side - especially if you need to hash IP addresses before they leave your environment.

Before you begin

You'll need the following information ready:

• A source name for this exposure source.
• A retention period (in days) for how long records should be kept.
• Your Hash Salt (if you're salting hashed IPs).
• The column names in your CSV files that correspond to MX8 Labs' required fields.
• Your IAM Role ARN if you want MX8 Labs to grant your AWS role upload permissions (this maps to the External ARN field).

Step 1 - Open the creation dialog

Navigate to your exposure sources and click Create Exposure Source. Select the S3 snapshot card.

Step 2 - Configure basic settings

Fill in the top-level fields:

• Source Name - A descriptive label for this source. This cannot be changed after creation.
• Retention Days - How long MX8 Labs retains exposure records for matching. Defaults to 7 days but can be set longer if your campaign requires it.
• Enabled - On by default. Toggle off to configure without activating.

Step 3 - Add dimensions

Dimensions work the same way as they do for pixel sources - they're additional attributes attached to each exposure record, used as aggregation buckets. Type a dimension name into the Add Dimension field and press Enter or click + Add Dimension.

Step 4 - Configure field mappings

This is where you tell MX8 Labs how your CSV columns map to the fields it needs. Your column names don't need to match MX8 Labs' - you just need to specify which of your columns corresponds to each field.

Required fields:

• Hash Salt - The salt value used when hashing IP addresses. If you don't use a salt, leave this empty.
• UID Field Mapping - The column name in your CSV that contains the user identifier (e.g., user_id).

Optional fields:

• Exposed IP Field Mapping - The column containing plaintext IP addresses. Provide this or Hashed IP Field Mapping.
• Hashed IP Field Mapping - The column containing hashed IP addresses. Provide this or Exposed IP Field Mapping.
• Brand Field Mapping - The column containing the brand name associated with each exposure.
• External ARN - Your IAM Role ARN. MX8 Labs uses this to grant your AWS role permission to upload files into your dedicated S3 prefix.

Step 5 - Configure dimension mappings

If you added dimensions in Step 3, scroll to the Dimension Mapping section and click the + button to map each dimension to the corresponding column in your CSV.

Step 6 - Create the source

Click Create to save. The source is now ready to receive files.

Note: The hash algorithm is currently fixed to MD5. Other algorithms are available on request - contact your MX8 Labs account team if you need a different algorithm.

What's next

• Server-Side File Delivery & Format Requirements - details on file format, naming, and upload process.
• IP Hashing Rules for Exposure Data - input formatting, salt handling, and output format guidance.