Connect a device.
Put it on a dashboard.

mosquitto_pub -h mqtt.iotaps.com -p 8883 --capath /etc/ssl/certs \
  -V mqttv5 -q 1 -i "$DEVICE_ID" \
  -u "$CREDENTIAL_ID" -P "$SECRET" \
  -t "v1/$ORG/$PROJECT/$DEVICE/telemetry" \
  -m '{"schema_version":1,"message_id":"m-1",
       "metrics":{"temperature_c":21.5}}'

import json, uuid
import paho.mqtt.client as mqtt

client = mqtt.Client(mqtt.CallbackAPIVersion.VERSION2,
                     client_id=DEVICE_ID, protocol=mqtt.MQTTv5)
client.username_pw_set(CREDENTIAL_ID, SECRET)
client.tls_set()
client.connect("mqtt.iotaps.com", 8883)

msg = {"schema_version": 1, "message_id": str(uuid.uuid4()),
       "metrics": {"temperature_c": 21.5}}
client.publish(TOPIC, json.dumps(msg), qos=1).wait_for_publish()

import mqtt from "mqtt";
import { randomUUID } from "node:crypto";

const client = mqtt.connect("mqtts://mqtt.iotaps.com:8883", {
  clientId: DEVICE_ID, username: CREDENTIAL_ID, password: SECRET,
});
client.publish(TOPIC, JSON.stringify({
  schema_version: 1, message_id: randomUUID(),
  metrics: { temperature_c: 21.5 },
}), { qos: 1 });