Tenant Context Propagation

public final class TenantContextHolder {
    private static final ThreadLocal<TenantContext> CONTEXT = new ThreadLocal<>();
 
    public static void setTenantId(String tenantId) {
        CONTEXT.set(new TenantContext(tenantId, null, Map.of()));
    }
 
    public static Optional<String> getTenantId() {
        return getContext().map(TenantContext::tenantId);
    }
 
    public static String requireTenantId() {
        return requireContext().tenantId();
    }
 
    public static void clear() {
        CONTEXT.remove();
    }
}

public record TenantContext(
    String tenantId,
    String userId,
    Map<String, Object> attributes
) {
    public TenantContext {
        if (tenantId == null || tenantId.isBlank()) {
            throw new IllegalArgumentException("Tenant ID cannot be null or blank");
        }
        attributes = attributes != null ? Map.copyOf(attributes) : Map.of();
    }
}

// Wrap a Runnable to preserve context
Runnable wrapped = TenantContextHolder.wrapWithContext(() -> {
    processInBackground();
});
executorService.submit(wrapped);

from contextvars import ContextVar
 
_tenant_id: ContextVar[str] = ContextVar('tenant_id')
 
def get_tenant_id() -> str:
    return _tenant_id.get()
 
def set_tenant_id(tenant_id: str) -> None:
    _tenant_id.set(tenant_id)