Data — Recipes

import { Data } from "@clutchcall/sdk/data";

const enc = (o: unknown) => new TextEncoder().encode(JSON.stringify(o));
const deviceId = process.argv[2] ?? "device-7";

const data = new Data({
  token:    process.env.CLUTCHCALL_CREDENTIALS!,
  clientId: deviceId,
});

// 1. Retained boot state — sticks for late joiners.
await data.publish({
  topic:    `devices/${deviceId}/state`,
  payload:  enc({ online: true, version: "1.4.2" }),
  retained: true,
});

// 2. Telemetry on the lossy lane; alert reliably past a threshold.
const timer = setInterval(async () => {
  const temp = 20 + Math.random() * 8;
  await data.publish({
    topic:   `sensors/${deviceId}/temperature`,
    payload: new TextEncoder().encode(temp.toFixed(2)),
  });
  if (temp > 27) {
    await data.publish({
      topic:    `events/alerts/${deviceId}`,
      payload:  enc({ kind: "over_temp", temp }),
      reliable: true,
    });
  }
}, 1000);

// 3. Clean shutdown — clear retained state, then close.
process.on("SIGTERM", async () => {
  clearInterval(timer);
  await data.publish({
    topic:    `devices/${deviceId}/state`,
    payload:  new Uint8Array(0),   // zero-length clears the retained value
    retained: true,
  });
  await data.close();
  process.exit(0);
});

import { Data, type DataMessage } from "@clutchcall/sdk/data";

const dec = (m: DataMessage) => new TextDecoder().decode(m.payload);
const online  = new Map<string, boolean>();
const lastTemp = new Map<string, number>();

const data = new Data({
  token:    process.env.CLUTCHCALL_CREDENTIALS!,
  clientId: "dashboard",
  onState:  (s) => console.log("session:", s),
});

// Roster: retained snapshots arrive first, then live changes.
await data.subscribe({ topicFilter: "devices/+/state" }, (msg) => {
  const id = msg.topic.split("/")[1];
  online.set(id, msg.payload.length > 0 && JSON.parse(dec(msg)).online === true);
  console.log(msg.retained ? "snapshot" : "update", id, online.get(id));
});

// Live telemetry from every device.
await data.subscribe({ topicFilter: "sensors/+/temperature" }, (msg) => {
  lastTemp.set(msg.fromClientId, Number(dec(msg)));
});

// Reliable alerts.
await data.subscribe({ topicFilter: "events/alerts/#" }, (msg) => {
  console.warn("ALERT", msg.fromClientId, dec(msg));
});