disconnect() {
		if (this.client) {
			if (this.useLegacy) {
				this.client.flush(() => {
					this.client.close();
					this.client = null;
				});
			} else {
				// NATS v2
				return this.client
					.flush()
					.then(() => this.client.close())
					.then(() => (this.client = null));
			}
		}
	}
Disconnect from a NATS server

@memberof NatsTransporter