compute-checksums

Type: Lambda function
Trigger: Scheduled EventBridge event
Dependencies: None

Overview

This Lambda function triggers S3 batch checksum jobs to verify data integrity across your buckets. It processes standard/public + replication bucket pairs together, ensuring both the source and replicated data are checksummed.

Invocation methods

Scheduled execution (production)

The Lambda is automatically triggered by a scheduled EventBridge event at regular intervals.

CLI testing

Compute checksums for a single bucket and its replication pair:

make run-compute-checksums b=digipres-dev1-private p=default

Parameters:

• b= — Standard or public stack bucket to checksum (required)
• p= — AWS profile (required)

Constraints:

• Only supports single bucket at a time
• Automatically paired with replication bucket
• Cannot directly specify a replication bucket

Remote trigger

Compute checksums for all stack buckets in a given stack:

make trigger f=compute-checksums s=digipres-dev1 p=default

Parameters:

• f= — Function name (compute-checksums)
• s= — Stack name (required)
• p= — AWS profile (required)

Behavior: Triggers jobs for ALL stack buckets in the specified stack.

Output

Function response

{
    "StatusCode": 200,
    "ExecutedVersion": "$LATEST"
}

Receipt files

For each bucket pair processed, a job receipt is uploaded to:

• metadata/latest/checksums/receipts/{source_job_id}.json
• metadata/latest/checksums/receipts/{repl_job_id}.json
• metadata/latest/checksums/receipts/{source_bucket_name}.json
• metadata/{date}/checksums/receipts/{source_bucket_name}.json

Purpose: The receipt is uploaded multiple times for different discovery paths:

• Job IDs — used by the Lambda checksum report process for internal tracking
• Bucket names — used by the CLI checksum report and for easier manual access

QA testing

Confirm:

• Jobs are created without errors
• Jobs are completed successfully
• All receipt files are generated and avaiable at the expected paths