* Merge expense-approval-bot into payments-dashboard Port the Slack reaction-driven expense routing workflow (receiver + processor) from expense-approval-bot into this stack as JavaScript ESM. Secrets copied to payments-dashboard/ prefix in Secrets Manager. * Fix review findings from PR #28 - Add length check before timingSafeEqual to prevent RangeError on malformed signatures (returns 401 instead of 500) - Check event.type === reaction_added to prevent reaction_removed from advancing expenses - Move getPermalink call behind isOrigin check to skip unnecessary API call on non-origin stage transitions
5.9 KiB
Payments Dashboard
AWS SAM application that ingests payment CSVs, syncs check data with Bank of America CashPro APIs, processes Gusto payroll confirmation emails into Slack notifications, surfaces an outstanding-payments dashboard in Slack, and routes expense approvals through a Slack reaction-driven workflow.
Architecture
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ProcessPayrollEmail — Lambda triggered by S3 (inbound email) and SQS (batch timer). SES receives Gusto payroll emails at
payroll@int.seahaven.com, stores them to S3, and this Lambda parses the email body, extracts financial data, and posts a combined Slack notification (employee payroll + contractor payments) after a 10-minute batching window. Runs outside VPC. -
ProcessPaymentCsv — Lambda triggered by S3 CSV upload. Parses Stampli payment exports, upserts to DynamoDB, and submits new/cancelled checks to the CashPro Check Management API.
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FetchBoaTransactions — Scheduled Lambda (weekdays 9am ET). Calls the CashPro Previous Day Transaction Inquiry API and matches cleared/returned checks back to DynamoDB records.
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SlackAppHome — Lambda behind API Gateway. Renders the payments dashboard on the Slack App Home tab with outstanding aging buckets and drill-down modals.
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ExpenseReceiver — Lambda behind API Gateway (
POST /slack/expense-events). Verifies the Slack signing secret (HMAC-SHA256), handles URL verification challenges, and async-invokes ExpenseProcessor. Runs outside VPC. -
ExpenseProcessor — Async Lambda invoked by ExpenseReceiver. Processes
:white_check_mark:reactions to advance expense messages through a four-stage Slack channel pipeline: Submitted → Processed → Authorized → Matched. Runs outside VPC.
ProcessPaymentCsv, FetchBoaTransactions, and SlackAppHome run inside a VPC with a NAT Gateway for a static outbound IP (required by BoA IP whitelisting). ProcessPayrollEmail, ExpenseReceiver, and ExpenseProcessor run outside the VPC.
Expense Approval Bot
Reaction-driven workflow that routes expense submissions through four Slack channels. A separate Slack app ("Expense Approval Bot") posts to a Submitted channel. Users react with ✅ to advance the message to the next stage.
Channel pipeline:
| Stage | Channel ID | Action on ✅ |
|---|---|---|
| Submitted | C0AQ2AWLNEN |
Thread reply on original, copy to Processed |
| Processed | C0APLSGABAB |
Delete from Processed, post to Authorized |
| Authorized | C0AQ09CDJH4 |
Delete from Authorized, post to Matched |
| Matched | C0APYUM1JFP |
Terminal stage (no further routing) |
Architecture: Two Lambdas — ExpenseReceiver (HTTP endpoint, signature verification, async invoke) and ExpenseProcessor (business logic). This is the same receiver/processor pattern used for Slack's 3-second timeout requirement.
Secrets (Secrets Manager):
| Secret | Purpose |
|---|---|
payments-dashboard/expense-slack-token |
Slack Bot token for the Expense Approval Bot app |
payments-dashboard/expense-slack-signing-secret |
Slack signing secret for request verification |
Payroll Email Pipeline
Gusto sends payroll confirmation emails when payroll is run. A Gmail filter on adam@seahavenind.com auto-forwards emails from automated@gusto.com and gustonoreply@gusto.com to payroll@int.seahaven.com.
Flow: Gmail forward → SES receipt rule → S3 bucket → Lambda parses email → DynamoDB (pending) → SQS delay queue (10 min) → Lambda batches all pending items for that date → single Slack message → DynamoDB (notified)
Deduplication: Each email is deduplicated by DynamoDB key (PAYROLL_EMAIL#employee#<date> or PAYROLL_EMAIL#contractor#<date>#<bank-suffix>). The batch post is deduplicated by PAYROLL_BATCH#<date>. All items have a 90-day TTL.
BoA CashPro API Integration
Two separate CashPro APIs are used, each with its own OAuth credentials:
| API | Purpose | Endpoint |
|---|---|---|
| Check Management | Issue and cancel checks | /cashpro/checkmanagement/v1/check-issues |
| Reporting (Transaction Inquiry) | Fetch previous-day transactions | /cashpro/reporting/v1/transaction-inquiries/previous-day |
Authentication flow:
- POST to
/authn/v1/client-authenticationwithapplicationID,client_id, andclient_secret - Receive a Bearer
access_token(valid 1 hour) - Pass the token in the
Authorizationheader for subsequent API calls
Base URLs:
- Production:
https://api.bofa.com - Sandbox:
https://api-sb.bofa.com
SSM Parameters
All BoA credentials and config are stored in AWS SSM Parameter Store (SecureString):
| Parameter | Description |
|---|---|
/payments-dashboard/boa-check-mgmt-app-id |
Check Management application ID |
/payments-dashboard/boa-check-mgmt-client-id |
Check Management client ID |
/payments-dashboard/boa-check-mgmt-token |
Check Management client secret |
/payments-dashboard/boa-reporting-app-id |
Reporting application ID |
/payments-dashboard/boa-account-info-client-id |
Reporting client ID |
/payments-dashboard/boa-account-info-token |
Reporting client secret |
/payments-dashboard/boa-account-number |
BoA account number |
/payments-dashboard/boa-company-id |
CashPro company ID (check management) |
/payments-dashboard/boa-bank-id |
BoA routing number |
/payments-dashboard/slack-bot-token |
Slack Bot OAuth token |
Scripts
| Script | Purpose |
|---|---|
scripts/test-boa-sandbox.js |
One-off sandbox connectivity test for both CashPro APIs |
scripts/seed-from-csv.js |
Seed DynamoDB from a local CSV file |
scripts/seed-bank-status.js |
Seed bank clear status data into DynamoDB |
Deployment
sam build
sam deploy --guided
The BOA_BASE_URL environment variable in template.yaml controls whether Lambdas hit production (https://api.bofa.com) or sandbox (https://api-sb.bofa.com). All other BoA config is read from SSM at runtime.