Pub/Sub API

WARNING: pubsub API is currently broken! The docs are also incorrect.

Pub/Sub provides real-time message fan-out. Publishers send messages to a channel, and subscribers receive them over Server-Sent Events or WebSockets.

Endpoints

Method	Endpoint	Description
POST	`/{plateId}/pubsub/{channel}/publish`	Publish a message
GET	`/{plateId}/pubsub/{channel}/subscribe`	Subscribe with SSE
GET	`/{plateId}/pubsub/{channel}/ws`	Subscribe with WebSocket
GET	`/{plateId}/pubsub/{channel}/client`	Generate a temporary client WebSocket path
POST	`/{plateId}/publish/{channel}`	Legacy publish alias
GET	`/{plateId}/subscribe/{channel}`	Legacy SSE alias
GET	`/{plateId}/ws/subscribe/{channel}`	Legacy WebSocket alias

Publish Simple Message

const plateId = "[id]";
const apiKey = "your-api-key";
const baseUrl = "[base-url]";

const response = await fetch(`${baseUrl}/${plateId}/pubsub/alerts/publish`, {
  method: "POST",
  headers: {
    "Authorization": apiKey,
    "Content-Type": "application/json"
  },
  body: JSON.stringify({
    message: "Server restarted"
  })
});

const data = await response.json();
console.log(data);

Publish Structured Object

const plateId = "[id]";
const apiKey = "your-api-key";
const baseUrl = "[base-url]";

const response = await fetch(`${baseUrl}/${plateId}/pubsub/user:123:events/publish`, {
  method: "POST",
  headers: {
    "Authorization": apiKey,
    "Content-Type": "application/json"
  },
  body: JSON.stringify({
    message: {
      type: "login",
      userId: "123",
      timestamp: "2026-03-15T12:00:00Z"
    }
  })
});

const data = await response.json();
console.log(data);

const plateId = "[id]";
const apiKey = "your-api-key";
const baseUrl = "[base-url]";

const eventSource = new EventSource(`${baseUrl}/${plateId}/pubsub/alerts/subscribe`, {
  headers: {
    "Authorization": apiKey
  }
});

eventSource.onmessage = (event) => {
  const data = JSON.parse(event.data);
  console.log("Received:", data);
};

eventSource.onerror = (error) => {
  console.error("Connection closed", error);
  eventSource.close();
};

const plateId = "[id]";
const apiKey = "your-api-key";
const baseUrl = "[base-url]";

const eventSource = new EventSource(
  `${baseUrl}/${plateId}/pubsub/user:*/subscribe?pattern=true`,
  {
    headers: {
      "Authorization": apiKey
    }
  }
);

eventSource.onmessage = (event) => {
  const data = JSON.parse(event.data);
  console.log("Received:", data);
};

const plateId = "[id]";
const apiKey = "your-api-key";
const baseUrl = "[base-url]".replace("http", "ws");

const ws = new WebSocket(`${baseUrl}/${plateId}/pubsub/alerts/ws`);

ws.onopen = () => {
  ws.send(JSON.stringify({ auth: apiKey }));
};

ws.onmessage = (event) => {
  const data = JSON.parse(event.data);
  console.log("Received:", data);
};

ws.onerror = (error) => {
  console.error("WebSocket error:", error);
};

ws.onclose = () => {
  console.log("WebSocket closed");
};

Generate Client WebSocket Path

Use this endpoint when you want to generate a temporary socket path for clients without exposing your API key.

GET /{plateId}/pubsub/{channel}/client

Query Parameters

Name	Type	Default	Description
`pattern`	boolean	`false`	Use pattern subscription mode (same behavior as SSE/WS subscribe routes)
`max_dur`	integer (ms)	`0`	Max connection duration in milliseconds (`0` = unlimited)
`expiry` or `ttl`	integer (ms)	`300000`	Max time allowed before the client connects (`0` to `600000`)
`max_uses`	integer	`1`	Number of allowed successful WebSocket connections (`0` = unlimited)

The response returns a relative path value. Append it to your base URL (with ws:// or wss://) to connect.

const plateId = "[id]";
const apiKey = "your-api-key";
const baseHttpUrl = "[base-url]";

const createResp = await fetch(
  `${baseHttpUrl}/${plateId}/pubsub/alerts/client?max_dur=60000&expiry=300000&max_uses=1`,
  {
    method: "GET",
    headers: {
      "Authorization": apiKey
    }
  }
);

const createData = await createResp.json();
const wsBase = baseHttpUrl.replace(/^http/, "ws");
const ws = new WebSocket(`${wsBase}${createData.data.path}`);

ws.onmessage = (event) => {
  console.log("Received:", JSON.parse(event.data));
};

Notes

Published payloads are JSON-encoded.
Subscription payloads decode JSON when possible and fall back to plain strings.
Client socket connect route (/{plateId}/s/{token}) can return: invalid_client_socket (unknown token), expired_client_socket (token TTL elapsed), and exhausted_client_socket (max uses reached).
Legacy publish/subscribe routes are still supported.

Pub/Sub API

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