Function ensure_topic 

pub async fn ensure_topic(
    bootstrap: &str,
    topic: &str,
    partitions: i32,
    security: Option<ClientSecurity>,
) -> Result<(), String>

Ensure topic exists with the given parameters. An already-exists response counts as success.

Errors

Returns an error when configuration is invalid, protocol encoding fails, the broker rejects the request, or transport I/O fails.