Latency statistics written once, thresholds read from CONFIG (closes #102)
check / check (push) Successful in 2m50s

A target's min, max, median and average latency now come from one list
of its answers, through latencyStats(), which the summary's figures use
too, so the median is written once. latencyHex() and latencyClass() read
one table of color limits in CONFIG. The health thresholds, the debug
log's length, the gateway check's timeout, the recovery probe's number
of hosts and interval, how often the rows are sorted and the delay
before the first sparkline resize are CONFIG entries, read where the
numbers were. HostState's minLatency(), maxLatency(), averageLatency()
and medianLatency() are gone; the statistics test reads historyStats().
Nothing the page does or shows changes. A unit test now covers the
summary's figures.

Model: opus-5-5
This commit was merged in pull request #108.
This commit is contained in:
2026-10-04 06:51:24 +02:00
parent d40e67d4ab
commit 161f955ae2
3 changed files with 129 additions and 92 deletions
+93 -82
View File
@@ -30,6 +30,39 @@ export const CONFIG = {
return [0, 1, 2, 3, 4, 5].map((i) => Math.round((d * i) / 5));
},
canvasHeight: 96,
// A latency figure and its sparkline take the color of the first entry
// whose limit, in ms, the latency is below.
latencyColors: [
{ below: 50, hex: "#22c55e", className: "text-green-500" },
{ below: 100, hex: "#84cc16", className: "text-lime-500" },
{ below: 200, hex: "#eab308", className: "text-yellow-500" },
{ below: 500, hex: "#f97316", className: "text-orange-500" },
{ below: Infinity, hex: "#ef4444", className: "text-red-500" },
],
// The health is offline when more than offlineTimeouts WAN hosts timed
// out or were unreachable and at most offlineReachable answered;
// otherwise degraded when more than degradedTimeouts timed out or were
// unreachable; otherwise slow when more than slowHosts answered after
// more than slowLatency ms.
offlineTimeouts: 10,
offlineReachable: 4,
degradedTimeouts: 4,
slowHosts: 3,
slowLatency: 1000,
// The debug log keeps its last maxLogEntries lines.
maxLogEntries: 1000,
// A gateway candidate that has not answered after gatewayTimeout ms is
// passed over.
gatewayTimeout: 1500,
// When no WAN host answers, the recovery probe checks recoveryProbeHosts
// random ones every recoveryProbeInterval ms.
recoveryProbeHosts: 4,
recoveryProbeInterval: 500,
// The rows are sorted after the first round that is not discarded, then
// every roundsPerSort rounds.
roundsPerSort: 10,
// The sparklines are sized and drawn again resizeDelay ms after start.
resizeDelay: 100,
};
// WAN endpoints to monitor. These are used for the aggregate health/stats
@@ -114,7 +147,8 @@ const debugLog = [];
const log = (() => {
function append(level, message) {
debugLog.push({ timestamp: new Date(), level, message });
if (debugLog.length > 1000) debugLog.splice(0, debugLog.length - 1000);
if (debugLog.length > CONFIG.maxLogEntries)
debugLog.splice(0, debugLog.length - CONFIG.maxLogEntries);
const panel = document.getElementById("debug-panel");
if (panel && !panel.classList.contains("hidden")) renderDebugLog();
}
@@ -174,7 +208,10 @@ async function detectGateway() {
const result = await Promise.any(
GATEWAY_CANDIDATES.map(async (url) => {
const controller = new AbortController();
const timeoutId = setTimeout(() => controller.abort(), 1500);
const timeoutId = setTimeout(
() => controller.abort(),
CONFIG.gatewayTimeout,
);
try {
await fetch(url, {
method: "GET",
@@ -199,6 +236,27 @@ async function detectGateway() {
// --- App State ---------------------------------------------------------------
// The min, max, median and average of latencies, a list of numbers, or all
// null when it is empty. The median of an even count is the mean of the
// middle two; it and the average are rounded.
function latencyStats(latencies) {
if (latencies.length === 0)
return { min: null, max: null, med: null, avg: null };
const sorted = [...latencies].sort((a, b) => a - b);
const mid = Math.floor(sorted.length / 2);
return {
min: sorted[0],
max: sorted[sorted.length - 1],
med:
sorted.length % 2
? sorted[mid]
: Math.round((sorted[mid - 1] + sorted[mid]) / 2),
avg: Math.round(
latencies.reduce((a, b) => a + b, 0) / latencies.length,
),
};
}
export class HostState {
constructor(host, pinned = false) {
this.name = host.name;
@@ -230,38 +288,16 @@ export class HostState {
this._trim();
}
averageLatency() {
const valid = this.history.filter((p) => p.latency !== null);
if (valid.length === 0) return null;
return Math.round(
valid.reduce((s, p) => s + p.latency, 0) / valid.length,
// The min, max, median and average latency of the checks in the history
// that got an answer.
historyStats() {
return latencyStats(
this.history
.filter((p) => p.latency !== null)
.map((p) => p.latency),
);
}
minLatency() {
const valid = this.history.filter((p) => p.latency !== null);
if (valid.length === 0) return null;
return Math.min(...valid.map((p) => p.latency));
}
maxLatency() {
const valid = this.history.filter((p) => p.latency !== null);
if (valid.length === 0) return null;
return Math.max(...valid.map((p) => p.latency));
}
medianLatency() {
const sorted = this.history
.filter((p) => p.latency !== null)
.map((p) => p.latency)
.sort((a, b) => a - b);
if (sorted.length === 0) return null;
const mid = Math.floor(sorted.length / 2);
return sorted.length % 2
? sorted[mid]
: Math.round((sorted[mid - 1] + sorted[mid]) / 2);
}
_trim() {
while (this.history.length > CONFIG.maxHistoryPoints)
this.history.shift();
@@ -288,33 +324,13 @@ export class AppState {
/** WAN-only stats from latest sample (excludes local) */
wanStats() {
const reachable = this.wan.filter((h) => h.lastLatency !== null);
const latencies = reachable.map((h) => h.lastLatency);
const total = this.wan.length;
if (latencies.length === 0)
return {
reachable: 0,
total,
min: null,
max: null,
med: null,
avg: null,
};
const sorted = [...latencies].sort((a, b) => a - b);
const mid = Math.floor(sorted.length / 2);
const med =
sorted.length % 2
? sorted[mid]
: Math.round((sorted[mid - 1] + sorted[mid]) / 2);
const latencies = this.wan
.filter((h) => h.lastLatency !== null)
.map((h) => h.lastLatency);
return {
reachable: latencies.length,
total,
min: Math.min(...latencies),
max: Math.max(...latencies),
med,
avg: Math.round(
latencies.reduce((a, b) => a + b, 0) / latencies.length,
),
total: this.wan.length,
...latencyStats(latencies),
};
}
@@ -340,12 +356,16 @@ export class AppState {
const timeouts = this.wan.filter(
(h) => h.status === "error" || h.status === "offline",
).length;
if (timeouts > 10 && reachable <= 4) return "offline";
if (timeouts > 4) return "degraded";
if (
timeouts > CONFIG.offlineTimeouts &&
reachable <= CONFIG.offlineReachable
)
return "offline";
if (timeouts > CONFIG.degradedTimeouts) return "degraded";
const slow = this.wan.filter(
(h) => h.lastLatency !== null && h.lastLatency > 1000,
(h) => h.lastLatency !== null && h.lastLatency > CONFIG.slowLatency,
).length;
if (slow > 3) return "slow";
if (slow > CONFIG.slowHosts) return "slow";
return "healthy";
}
@@ -557,21 +577,13 @@ export async function measureLatency(url, signal) {
export function latencyHex(latency) {
if (latency === null) return "#6b7280";
if (latency < 50) return "#22c55e";
if (latency < 100) return "#84cc16";
if (latency < 200) return "#eab308";
if (latency < 500) return "#f97316";
return "#ef4444";
return CONFIG.latencyColors.find((c) => latency < c.below).hex;
}
export function latencyClass(latency, status) {
if (status === "offline" || status === "error" || latency === null)
return "text-gray-500";
if (latency < 50) return "text-green-500";
if (latency < 100) return "text-lime-500";
if (latency < 200) return "text-yellow-500";
if (latency < 500) return "text-orange-500";
return "text-red-500";
return CONFIG.latencyColors.find((c) => latency < c.below).className;
}
// --- Sparkline Renderer ------------------------------------------------------
@@ -912,10 +924,7 @@ function updateHostRow(host, index) {
latencyEl.innerHTML = `<span class="text-gray-500">---</span>`;
}
const avg = host.averageLatency();
const med = host.medianLatency();
const min = host.minLatency();
const max = host.maxLatency();
const { min, med, avg, max } = host.historyStats();
if (host.status === "online" && avg !== null) {
statusEl.innerHTML = statusStatsHTML([
["min", min],
@@ -1182,8 +1191,9 @@ export async function tick(state, signal, onOffline) {
// rows whose check ended before the resume still read "paused"
state.allHosts.forEach((host, i) => updateHostRow(host, i));
// Sort after the first real check, then every 10 ticks thereafter
if (state.tickCount === 2 || state.tickCount % 10 === 1) {
// Sort after the first real check, then every CONFIG.roundsPerSort
// ticks thereafter
if (state.tickCount === 2 || state.tickCount % CONFIG.roundsPerSort === 1) {
sortAndRebuildWAN(state);
}
@@ -1206,9 +1216,10 @@ export async function tick(state, signal, onOffline) {
// --- Recovery Probe ----------------------------------------------------------
// When offline, check 4 random WAN hosts every 500ms, giving up the checks
// started 500ms before, so at most 4 are ever waiting. As soon as one
// answers, stop probing and start a new round at once.
// When offline, check CONFIG.recoveryProbeHosts random WAN hosts every
// CONFIG.recoveryProbeInterval ms, giving up the checks started one interval
// before, so at most that many are ever waiting. As soon as one answers,
// stop probing and start a new round at once.
function startRecoveryProbe(state, startRounds) {
if (state._recoveryProbeId) return; // already running
const candidates = [...state.wan];
@@ -1216,7 +1227,7 @@ function startRecoveryProbe(state, startRounds) {
const j = Math.floor(Math.random() * (i + 1));
[candidates[i], candidates[j]] = [candidates[j], candidates[i]];
}
const canaries = candidates.slice(0, 4);
const canaries = candidates.slice(0, CONFIG.recoveryProbeHosts);
log.notice(
`Recovery probe started (${canaries.map((h) => h.name).join(", ")})`,
);
@@ -1233,7 +1244,7 @@ function startRecoveryProbe(state, startRounds) {
startRounds();
});
}
}, 500);
}, CONFIG.recoveryProbeInterval);
}
function stopRecoveryProbe(state) {
@@ -1497,7 +1508,7 @@ async function init() {
});
window.addEventListener("resize", () => handleResize(state));
setTimeout(() => handleResize(state), 100);
setTimeout(() => handleResize(state), CONFIG.resizeDelay);
}
// Bootstrap only when loaded as the page: a real DOM containing the #app