https://github.com/apache/incubator-pulsar/wiki/PIP-11:-Short-topic-names
[Copying wiki text for easier quoting] ------------------------------ * **Status**: Proposal * **Author**: Matteo Merli * **Pull Request**: [ ] * **Mailing List discussion**: ## Motivation Pulsar was designed as a multi-tenant system from the very beginning. From this it originate the notions of tenants and namespaces to allow users to administrate and operate their own topics. In Pulsar, all these concepts are explicitly set in the namespace and topic names. The topic name is composed of all the names: ``` persistent://my-tenant/my-cluster/my-namespace/my-topic ``` In [PIP-10]( https://github.com/apache/incubator-pulsar/wiki/PIP-10:-Remove-cluster-for-namespace-and-topic-names), we have already introduced the proposal to hide the cluster name from the topic name, resulting in a topic name such as: ``` persistent://my-tenant/my-namespace/my-topic ``` This proposal is dependent on PIP-10 because it needs the cluster to not appear in the topic name. In many cases, when deploying Pulsar as a single tenant, users might not need all the "tenant" and "namespace" information, but currently it would have to do the following steps after deploying a Pulsar cluster, even when authorization is not required: * Create a "property" (or tenant) * Create a namespace Additionally, it forces the multi-tenant model even when it's not needed or when someone wants to just "play" with the system. For such reasons, this proposal is to introduce a default namespace that is always pre-created and a short notation for topic names. For example: * `my-topic` --> `persistent://public/default/my-topic` If omitted, the `persistent` or `non-persistent` schema, will be defaulted to `persistent`, even when using longer form of topic name: * `tenant/namespace/my-topic` --> `persistent://tenant/namespace/my-topic` The goal is to be able to use the short form in client API and tools: ```java PulsarClient client = PulsarClient.create("pulsar://localhost:6650"); Producer producer = client.createProducer("my-topic"); producer.send(message); ``` At the same time, all CLI tools will recognize the short notation as well, for example: ```shell $ bin/pulsar-admin persistent stats my-topic ``` It will be equivalent to: ```shell $ bin/pulsar-admin persistent stats persistent://public/default/my-topic ``` ## Changes The changes will be mostly on the surface: * Introduce the concept of `public` tenant (property). This tenant will be already pre-created when initializing a Pulsar cluster. When authorization is enabled, it would be responsibility of the administrator to grant permissions to use it. * Introduce the concept of `public/default` namespace. This will be pre-created at the cluster initialization. The default namespace will be a regular namespace that the administrator can configure in the same way as all other namespaces * In client library and tools, translate all the short topic names by adding the default namespace: `my-topic` --> `persistent://public/default/my-topic` -- Matteo Merli <mme...@apache.org>
