An MQTT broker with the ingestion pipeline and storage already behind it.

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_ID/$PROJECT_ID/$DEVICE_ID/telemetry" \
  -m '{"schema_version":1,"message_id":"m-0001",
       "metrics":{"temperature_c":21.5}}'

import json, uuid
import paho.mqtt.client as mqtt  # paho-mqtt 2.x

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

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

import mqtt from "mqtt";  // mqtt.js 5.x
import { randomUUID } from "node:crypto";

const client = mqtt.connect("mqtts://mqtt.iotaps.com:8883", {
  clientId: DEVICE_ID, username: CREDENTIAL_ID, password: SECRET,
  protocolVersion: 5,
});

client.on("connect", () => {
  const message = { schema_version: 1, message_id: randomUUID(),
                    metrics: { temperature_c: 21.5 } };
  client.publish(TOPIC, JSON.stringify(message), { qos: 1 },
                 () => client.end());
});