Given the fact that a Consumer in Kafka can be configured to receive messages only from one partition, I haven't seen a configuration approach for this.
How do I tell a Kafka broker:
That I'm a CONSUMER A with this ID, under this GROUP L, subscribing to TOPIC X, willing to get the stream of PARTITION A?
And then, start another CONSUMER B, under GROUP L, which subscribes to TOPIC X, willing to get the stream of PARTITION B?
In other words, as in the scenario described by Kafka,
How do I start a consumer subscribing to a wall feed of a specific user? Can I start a consumer when a user logs in, consumer his/her partition form the topic and send the feed to the client?