Files
PromdataPanel/server/latency-service.js
2026-04-06 00:24:33 +08:00

78 lines
2.9 KiB
JavaScript

const axios = require('axios');
const cache = require('./cache');
const db = require('./db');
const POLL_INTERVAL = 10000; // 10 seconds
async function pollLatency() {
try {
const [routes] = await db.query(`
SELECT r.*, s.url
FROM latency_routes r
JOIN prometheus_sources s ON r.source_id = s.id
WHERE s.type = 'blackbox'
`);
if (routes.length === 0) return;
// Poll each route
await Promise.allSettled(routes.map(async (route) => {
try {
// Blackbox exporter probe URL
// We assume ICMP module for now. If target is a URL, maybe use http_2xx
let module = 'icmp';
let target = route.latency_target;
if (target.startsWith('http://') || target.startsWith('https://')) {
module = 'http_2xx';
}
const probeUrl = `${route.url.replace(/\/+$/, '')}/probe?module=${module}&target=${encodeURIComponent(target)}`;
const startTime = Date.now();
const response = await axios.get(probeUrl, { timeout: 5000 });
const duration = (Date.now() - startTime) / 1000; // Fallback to local timing if parsing fails
// Parse prometheus text format for probe_duration_seconds
let latency = null;
const lines = response.data.split('\n');
for (const line of lines) {
// Match "probe_duration_seconds 0.123" or "probe_duration_seconds{...} 0.123"
const match = line.match(/^probe_duration_seconds(?:\{.*\})?\s+([\d.]+)/);
if (match) {
latency = parseFloat(match[1]) * 1000; // to ms
break;
}
}
if (latency === null) {
// Fallback to local response time if metric not found in output
latency = duration * 1000;
}
// Save to Valkey
await cache.set(`latency:route:${route.id}`, latency, 60);
// console.log(`[Latency] Route ${route.id} (${target}): ${latency.toFixed(2)}ms`);
} catch (err) {
// console.error(`[Latency] Error polling route ${route.id}:`, err.message);
await cache.set(`latency:route:${route.id}`, null, 60);
}
}));
} catch (err) {
console.error('[Latency] Service error:', err.message);
}
}
let intervalId = null;
function start() {
if (intervalId) clearInterval(intervalId);
pollLatency(); // initial run
intervalId = setInterval(pollLatency, POLL_INTERVAL);
console.log('[Latency] Background service started (polling Blackbox Exporter directly)');
}
module.exports = {
start
};