Multi Tenant Kafka Header Organization Context

Multi-tenant Kafka header → context propagation

Keep tenant id out of message payloads when possible; carry it in a Kafka header so routing can happen without deserializing the body. On the consumer side, extract once and push into a TenantContextHolder ThreadLocal before dispatching to async handlers.

Shape

• Producer sets header organizationId (or tenantId) on every record.
• Consumer reads header, wraps payload + header into an event wrapper (e.g. CollectionEvent(organizationId, payload)).
• Before handing to an executor/BlockingQueue consumer, set TenantContextHolder.set(orgId); always clear in finally.
• Handler threads must inherit the context — use DelegatingSecurityContextExecutor-style wrapping or set inside the runnable, NOT by relying on InheritableThreadLocal across a long-lived pool.

Steps

1. Define TenantContextHolder with over a plain .