Kafka Events

21 Kafka event topics published and consumed by the Wallet Service using CloudEvents 1.0.

Event Format

All events follow the CloudEvents 1.0 specification, partitioned by tenant_id for multi-tenant isolation. Topic naming: eventzr.wallet.<entity>.<action>.v1

Published Events (17)

Topic	Category	Description
`eventzr.wallet.created.v1`	wallet-lifecycle	New wallet created for a user or team
`eventzr.wallet.balance.updated.v1`	wallet-lifecycle	Wallet balance changed (credit, debit, or adjustment)
`eventzr.wallet.frozen.v1`	wallet-lifecycle	Wallet frozen by admin action
`eventzr.wallet.closed.v1`	wallet-lifecycle	Wallet permanently closed
`eventzr.wallet.transaction.created.v1`	transactions	New transaction initiated
`eventzr.wallet.transaction.completed.v1`	transactions	Transaction successfully completed
`eventzr.wallet.transaction.failed.v1`	transactions	Transaction failed to process
`eventzr.wallet.refund.completed.v1`	refunds	Refund successfully processed
`eventzr.wallet.refund.failed.v1`	refunds	Refund processing failed
`eventzr.wallet.escrow.created.v1`	escrow	New escrow created and funded
`eventzr.wallet.escrow.released.v1`	escrow	Escrow funds released to recipient
`eventzr.wallet.escrow.refunded.v1`	escrow	Escrow funds returned to payer
`eventzr.wallet.payment-method.added.v1`	payment-methods	Payment method registered
`eventzr.wallet.payment-method.removed.v1`	payment-methods	Payment method deleted
`eventzr.wallet.payment-method.verified.v1`	payment-methods	Payment method verification completed
`eventzr.wallet.split.completed.v1`	split-payments	Split payment successfully distributed
`eventzr.wallet.split.failed.v1`	split-payments	Split payment distribution failed

Consumed Events (4)

Topic	Source Service	Description
`eventzr.subscription.charge.posted.v1`	subscriptions-svc	Subscription charge to debit from wallet
`eventzr.ticketing.purchase.completed.v1`	ticketing-svc	Ticket purchase requiring wallet debit
`eventzr.booking.deposit.received.v1`	booking-svc	Booking deposit credited to wallet
`eventzr.user.kyc.verified.v1`	user-svc	KYC verification enabling higher wallet limits

CloudEvents Envelope Example

eventzr.wallet.transaction.completed.v1json

{
  "specversion": "1.0",
  "type": "eventzr.wallet.transaction.completed.v1",
  "source": "wallet-svc",
  "id": "evt_01H5ABCDEFGH",
  "time": "2026-02-21T10:00:00.000Z",
  "datacontenttype": "application/json",
  "data": {
    "transactionId": "txn_01H5ABCDEFGH",
    "walletId": "wal_01H5ABCDEFGH",
    "tenantId": "00000000-0000-4000-a000-000000000001",
    "type": "DEBIT",
    "amount": "50.00",
    "currency": "USD",
    "description": "Ticket purchase",
    "status": "COMPLETED",
    "balanceAfter": "450.00"
  }
}

Infrastructure

Property	Value
Broker	`Amazon MSK Serverless (Kafka 3.6)`
Protocol	`kafka-secure (SASL IAM)`
Partition Key	`tenant_id`
Outbox Pattern	KafkaOutbox table (at-least-once delivery)
DLQ	KafkaDlq table (failed after max retries)