PO Ingest

Coupa purchase-order email ingestion pipeline. SES receives Amazon PO emails, Claude extracts structured data, and the result lands in the shared purchase-orders DynamoDB table.

Flow

1. Coupa sends a PO email to amazon_po@int.seahaven.com.
2. SES (using the shared INBOUND_MAIL rule set) drops the raw MIME into s3://po-ingest-emails-{AccountId}/inbound/.
3. S3 ObjectCreated fires the po-email-processor Lambda.
4. The Lambda parses the email, sends it to Claude Haiku 4.5 for structured JSON extraction, and writes to DynamoDB.
   • email_type: new_po — conditional PutItem on purchase-orders (idempotent on po_number).
   • email_type: cancellation — UpdateItem marking the existing row Cancelled.
5. DynamoDB Streams (NEW_AND_OLD_IMAGES) on purchase-orders feeds two downstream consumers:
   • LedgerFlow (seahaven-slack-bot/po-sync) — daily KB sync.
   • Verified-sites pipeline (po-ingest-site-extractor) — real-time site address extraction (see below).

A separate po-web-ui Lambda (Function URL, unauthenticated) renders a simple HTML dashboard scanning the table.

Verified-sites pipeline

The po-ingest-site-extractor Lambda is triggered by the DynamoDB Stream on every PO INSERT/MODIFY. It:

1. Extracts an Amazon facility site code from ship_to.name using a regex cascade (parentheses, LLC - CODE, Station CODE, DS - CODE) with a fallback to the first line_items description.
2. Parses ship_to.address into structured fields (street, city, state, zip).
3. Upserts to the verified-sites DynamoDB table — atomically increments poCount and appends the PO number to sourcePOs.

POs with no extractable site code are logged and skipped.

Backfill stats (initial run): 14,825 POs scanned → 9,900 with extractable site codes → 1,100 unique sites.

Architecture

• IaC: AWS CDK (Python), stack name PoIngestStack, region us-east-1.
• Lambdas (all Python 3.12, arm64, 60-day log retention):
  • po-email-processor — S3-triggered, parses PO emails via Claude Haiku.
  • po-web-ui — Function URL, HTML dashboard.
  • po-ingest-site-extractor — DynamoDB Streams-triggered, extracts site addresses.
• Storage:
  • S3 po-ingest-emails-{AccountId} — 90-day lifecycle expiry.
  • DynamoDB purchase-orders — owned by this stack, Streams enabled (NEW_AND_OLD_IMAGES).
  • DynamoDB verified-sites — PK siteCode, GSI by-state on state.
• Secrets: Anthropic API key in Secrets Manager at po-ingest/anthropic-api-key.
• SES: adds the PoEmailRule to the existing INBOUND_MAIL receipt rule set (shared with workorder-ingest).

Setup

1. Bootstrap CDK in the account if you haven't already: cdk bootstrap aws://{AccountId}/us-east-1.
2. Store the Anthropic API key:

   aws secretsmanager create-secret \
     --name po-ingest/anthropic-api-key \
     --secret-string "sk-ant-..."
   

3. Install Lambda dependencies into the deployable package directory (gitignored):

   pip install -r lambdas/email_processor/requirements.txt -t lambdas/email_processor/package/
   

4. Deploy:

   cd cdk
   pip install -r requirements.txt
   cdk deploy
   

5. The WebUIUrl CloudFormation output is the dashboard URL.

Reprocessing

To re-run the processor against every email still sitting in inbound/ (useful after a parser change):

python scripts/reprocess.py            # dry-run — lists keys
python scripts/reprocess.py --execute  # invokes po-email-processor for each

Inserts are conditional on po_number, so re-processing existing POs is a no-op.

Backfilling verified sites

The stream Lambda handles all future POs automatically. To backfill from historical PO data (one-time):

python scripts/backfill_sites.py

Uses the same extraction logic as the Lambda. Idempotent — safe to re-run.