Kafka

Topics found in the repository

Topic	Producer	Consumer
order-created	order-service	notification-service, analytics-service
payment-success	payment-service	order-service
payment-failed	payment-service	analytics-service
payment-completed	none in current code	analytics-service

Event schemas

order-created

• orderId
• userId
• email
• totalAmount
• items[]
• firstName
• phoneNumber
• status

payment-success

• paymentId
• checkoutId
• userId
• transactionId
• amount
• items[]
• email
• firstName
• phoneNumber

payment-failed

• paymentId
• checkoutId
• userId
• transactionId
• amount

Checkout/event flow

Retry / delivery notes

• Producers use Spring Kafka KafkaTemplate
• payment-service waits on .get() for publish success/failure
• order-service publishes after transaction commit using TransactionSynchronizationManager
• analytics-service adds an application-level deduplication table via processed_events

Known inconsistency

analytics-service listens for payment-completed, but payment-service publishes payment-success. Documentation intentionally keeps this mismatch visible because it exists in the repository today.