Remote Procedure Call (RPC)

Make request/reply calls from your app to devices. Unlike commands, RPC waits for the device to respond before returning.

Access via app.rpc.

API

call()

Send an RPC request to a device and wait for its response.

JavaScript

await app.rpc.call(params)

Python

await app.rpc.call(params)

Parameter	Type	Description
device_ident	string	The device identifier
name	string	The RPC name (must match a listener on the device)
data	any	The request payload
timeout	number	(optional) Timeout in seconds. Default: 10

Returns the response from the device

Throws TimeoutError if the device doesn't respond within the timeout

JavaScript

const response = await app.rpc.call({
  device_ident: "sensor_01",
  name: "get_status",
  data: { include_logs: true },
  timeout: 20,
});

console.log("Uptime:", response.data.uptime);
console.log("Firmware:", response.data.firmware);

Python

response = await app.rpc.call({
    "device_ident": "sensor_01",
    "name": "get_status",
    "data": {"include_logs": True},
    "timeout": 20,
})

print("Uptime:", response["data"]["uptime"])
print("Firmware:", response["data"]["firmware"])

Response Format

The device responds using request.respond(data) or request.error(data) from the Device SDK RPC module. The response object contains:

Field	Description
status	"ok" for success, "error" for errors
data	The response payload from the device

Success response:

{
  "status": "ok",
  "data": {
    "uptime": 86400,
    "firmware": "1.2.0",
    "temperature": 22.5
  }
}

Error response (when the device calls request.error()):

{
  "status": "error",
  "data": {
    "message": "Unknown service: analytics"
  }
}

Error Handling

JavaScript

try {
  const response = await app.rpc.call({
    device_ident: "sensor_01",
    name: "get_status",
    data: {},
    timeout: 5,
  });

  if (response.status === "error") {
    console.error("Device error:", response.data);
  } else {
    console.log("Success:", response.data);
  }
} catch (err) {
  // TimeoutError — device didn't respond in time
  console.error("RPC timed out:", err.message);
}

Python

try:
    response = await app.rpc.call({
        "device_ident": "sensor_01",
        "name": "get_status",
        "data": {},
        "timeout": 5,
    })

    if response["status"] == "error":
        print("Device error:", response["data"])
    else:
        print("Success:", response["data"])
except TimeoutError:
    print("RPC timed out")