RPC Call Reply
Use this node to send the current message data as a reply to a device-originated RPC request — for example, returning computed server data to a device that called getReferenceData, or confirming a command execution back to the requesting device.
Configuration
Section titled “Configuration”- Service Id — metadata key that holds the service identifier. Default:
serviceId. - Session Id — metadata key that holds the session identifier. Default:
sessionId. - Request Id — metadata key that holds the request identifier. Default:
requestId.
Message processing algorithm
Section titled “Message processing algorithm”- Verify that the originator is a
DEVICE. If not, route viaFailure. - Extract
serviceId,sessionId, andrequestIdfrom message metadata. If any is missing, route viaFailure. - Verify that message data is not empty. If empty, route via
Failure. - Check for an
edgeIdin message metadata:- Present: save the reply to the edge event queue for asynchronous delivery to the edge device.
- Absent: send the reply directly to the device via the RPC service.
- Route the original message via
Success.
Output connections
Section titled “Output connections”| Connection | Condition |
|---|---|
Success | Reply sent (or queued for edge delivery). Outgoing message is unchanged. |
Failure | Originator is not a DEVICE, missing serviceId/sessionId/requestId, empty data, parse error, or unexpected error. |
Examples
Section titled “Examples”Example 1 — Return current server time
Section titled “Example 1 — Return current server time”Originator: DEVICE | Metadata (from TO_SERVER_RPC_REQUEST):
{ "serviceId": "monolith", "sessionId": "550e8400-e29b-41d4-a716-446655440000", "requestId": "12345"}Data (built by earlier rule nodes):
{ "timestamp": 1727712000000}{ "serviceIdMetaDataAttribute": "serviceId", "sessionIdMetaDataAttribute": "sessionId", "requestIdMetaDataAttribute": "requestId"}Result: timestamp returned to the device as the RPC response. Routes via Success.
JSON schema
Section titled “JSON schema”{ "$schema": "https://json-schema.org/draft/2020-12/schema", "title": "TbSendRpcReplyNodeConfiguration", "type": "object", "required": ["serviceIdMetaDataAttribute", "sessionIdMetaDataAttribute", "requestIdMetaDataAttribute"], "additionalProperties": false, "properties": { "serviceIdMetaDataAttribute": { "type": "string" }, "sessionIdMetaDataAttribute": { "type": "string" }, "requestIdMetaDataAttribute": { "type": "string" } }}