Multi-Tenancy

Topic Naming Rule

Pulsar supports multi-tenancy. The client side should specifies a long topic name URL like "persistent://tenant/ns/topic". KSN leverages the multi-tenancy from Pulsar and keeps the compatibility with the short topic names in Kafka.

For Kafka client users, they should follow the topic naming rule in this section. Otherwise, unexpected behaviors might happen.

You should specific topic names like:

topic: it refers the topic persistent://public/default/topic in the public/default namespace.
tenant.ns.topic: it refers the topic persistent://tenant/ns/topic in the tenant/ns namespace.
tenant.ns.xxx.yyy: it refers the topic persistent://tenant/ns/xxx.yyy in the tenant/ns namespace.

In short, use a short topic name if you don't care about multi-tenancy. Otherwise, add the namespace prefix for topics in non-default namespaces. Besides, Kafka clients can only access namespaces whose name doe not contain any dot character.

Note

In early versions of KSN, the topic naming style is similar to Pulsar, i.e. you need to specify tenant/ns/topic rather than tenant.ns.topic to access topic topic in namespace tenant/ns.

Listing topics

By default, when listing topics via Kafka clients or Kafka CLI, only topics in the default namespace will be listed. This behavior is intended to avoid accessing other namespaces that you might not have permission to access.

If you want to list topics in some other namespaces (e.g. tenant1/ns1 and tenant2/ns2), you can use Pulsar admin CLI to update the configuration dynamically:

./bin/pulsar-admin brokers update-dynamic-config --config kopAllowedNamespaces --value "tenant1/ns1,tenant2/ns2"