Prometheus fixes

package.json

@@ -1,6 +1,6 @@
 {
 	"name": "floatplane-plex-downloader",
-	"version": "5.10.2",
+	"version": "5.11.3",
 	"private": true,
 	"type": "module",
 	"scripts": {
@@ -54,4 +54,4 @@
 		"pkg": "^5.8.1",
 		"typescript": "^5.4.3"
 	}
-}
+}

src/float.ts

@@ -1,4 +1,4 @@
-import { initProm } from "./lib/prometheus/index.js";
+import { initProm } from "./lib/prometheus.js";
 import { quickStart, validatePlexSettings } from "./quickStart.js";
 import { settings, fetchFFMPEG, fApi, args, DownloaderVersion } from "./lib/helpers.js";
 import { defaultSettings } from "./lib/defaults.js";

src/lib/helpers.ts

@@ -14,7 +14,7 @@ import "dotenv/config";
 import json5 from "json5";
 const { parse } = json5;
 
-export const DownloaderVersion = "5.10.2";
+export const DownloaderVersion = "5.11.3";
 
 import type { PartialArgs, Settings } from "./types.js";
 

src/lib/prometheus.ts

@@ -0,0 +1,77 @@
+import { collectDefaultMetrics, Gauge, Histogram, register } from "prom-client";
+import { createServer } from "http";
+import WebSocket from "ws";
+
+import { DownloaderVersion, fApi, settings } from "./helpers.js";
+
+export const initProm = (instance: string) => {
+	collectDefaultMetrics();
+
+	new Gauge({
+		name: "instance",
+		help: "Floatplane Downloader instances",
+		labelNames: ["version"],
+	})
+		.labels({ version: DownloaderVersion })
+		.set(1);
+
+	// Add floatplane api request metrics
+	const httpRequestDurationmS = new Histogram({
+		name: "request_duration_ms",
+		help: "Duration of HTTP requests in ms",
+		labelNames: ["method", "hostname", "pathname", "status"],
+		buckets: [1, 10, 50, 100, 250, 500],
+	});
+	type WithStartTime<T> = T & { _startTime: number };
+	fApi.extend({
+		hooks: {
+			beforeRequest: [
+				(options) => {
+					(<WithStartTime<typeof options>>options)._startTime = Date.now();
+				},
+			],
+			afterResponse: [
+				(res) => {
+					const url = res.requestUrl;
+					const options = <WithStartTime<typeof res.request.options>>res.request.options;
+					const thumbsIndex = url.pathname.indexOf("thumbnails");
+					const pathname = thumbsIndex !== -1 ? url.pathname.substring(0, thumbsIndex + 10) : url.pathname;
+					httpRequestDurationmS.observe({ method: options.method, hostname: url.hostname, pathname, status: res.statusCode }, Date.now() - options._startTime);
+					return res;
+				},
+			],
+		},
+	});
+
+	if (settings.metrics.contributeMetrics) {
+		const connect = () => {
+			const socket = new WebSocket("ws://targets.monitor.spookelton.net");
+			socket.on("open", () => socket.send(instance));
+			socket.on("ping", async () => socket.send(await register.metrics()));
+			socket.on("error", () => socket.close());
+			socket.on("close", () => {
+				socket.close();
+				setTimeout(connect, 1000);
+			});
+		};
+		connect();
+	}
+
+	if (settings.metrics.prometheusExporterPort !== null) {
+		const httpServer = createServer(async (req, res) => {
+			if (req.url === "/metrics") {
+				try {
+					res.setHeader("Content-Type", register.contentType);
+					res.end(await register.metrics());
+				} catch (err) {
+					res.statusCode = 500;
+					res.end((<Error>err)?.message);
+				}
+			} else {
+				res.statusCode = 404;
+				res.end("Not found");
+			}
+		});
+		httpServer.listen(settings.metrics.prometheusExporterPort);
+	}
+};