NodeJS Message router implementation

Hello,

My goal is to ensure a consumer will always receive key associated messages.
But from my tests, on adding/removing consumers there are cases where Pulsar will do a rebalance.

So I think my best shot is to publish to a specific partition and subscribe to this specific partition with my customer.

So what I would do is implement the Message Router interface [as explained here](https://pulsar.apache.org/docs/3.0.x/concepts-messaging/#routing-modes).
But I could not make it in the Node.js client, as it does not seem to exist.

Will that be implemented in the future ?

Let me know if I'm mistaking or if it's unclear, as I'm pretty new to Apache Pulsar.
Thanks for reading.

Comienza leyendo la documentación enlazada sobre los modos de enrutamiento de Pulsar; después, inspecciona el cliente de Node.js en busca de sus Producer APIs y de cualquier interfaz de Message Router o pruebas de enrutamiento existentes. Se considera terminado cuando el cliente expone el comportamiento de message-router solicitado y admite enrutar mensajes con clave a la partición prevista sin rebalanceo no deseado.

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