Files
mqtt-ingest/app/src/handlers/edge5i-modbus.ts

56 lines
1.4 KiB
TypeScript

import { postCloudIngest } from '../cloud-ingest.js'
import { log } from '../helpers/log.js'
import type { TopicHandler } from '../types.js'
const EDGE = 'edge5i'
const REGISTER_COUNT = 100
type DemoModbusMetric = {
edge: string
timestamp: string
tag: string
value: number
}
function parseValues(payload: Buffer): number[] {
const values = JSON.parse(payload.toString('utf8')) as number[]
assertRegisterCount(values)
return values
}
function assertRegisterCount(values: number[]): void {
if (values.length !== REGISTER_COUNT) {
throw new Error(`Expected ${REGISTER_COUNT} modbus values, got ${values.length}`)
}
}
function toMetrics(values: number[], timestamp: string): DemoModbusMetric[] {
return values.map((value, index) => ({
edge: EDGE,
timestamp,
tag: `register-${String(index).padStart(3, '0')}`,
value,
}))
}
async function postMetrics(metrics: DemoModbusMetric[]): Promise<void> {
for (const metric of metrics) {
const response = await postCloudIngest(metric)
if (!response.ok) {
const text = await response.text()
throw new Error(text)
}
}
log(`${EDGE}.modbus.posted ${metrics.length} metrics`)
}
export const handle: TopicHandler = async (topic, payload) => {
log(`${EDGE}.modbus.received ${topic} ${payload.length} bytes`)
const values = parseValues(payload)
const metrics = toMetrics(values, new Date().toISOString())
await postMetrics(metrics)
}