Replace endpointHitCounter

Track summary statistic of total HTTP response durations using a
middleware that applies for all requests instead of having every request
needing to update the hit counter manually.  Deprecates
endpointHitCounter.

packages/master/src/Master.js

@@ -6,7 +6,7 @@ const fs = require("fs-extra");
 const http = require("http");
 const https = require("https");
 const path = require("path");
-
+const stream = require("stream");
 
 const libConfig = require("@clusterio/lib/config");
 const libData = require("@clusterio/lib/data");
@@ -26,9 +26,10 @@ const UserManager = require("./UserManager");
 const WsServer = require("./WsServer");
 
 
-const hitCounter = new libPrometheus.Counter(
-	"clusterio_master_http_hits_total",
-	"How many HTTP requests in total have been received"
+const endpointDurationSummary = new libPrometheus.Summary(
+	"clusterio_master_http_endpoint_duration_seconds",
+	"Time it took to respond to a an HTTP request",
+	{ labels: ["route"] }
 );
 
 /**
@@ -487,7 +488,15 @@ class Master {
 
 	static addAppRoutes(app, pluginInfos) {
 		app.use((req, res, next) => {
-			hitCounter.inc();
+			let start = process.hrtime.bigint();
+			stream.finished(res, () => {
+				let routePath = "static";
+				if (req.route && req.route.path) {
+					routePath = req.route.path;
+				}
+				let end = process.hrtime.bigint();
+				endpointDurationSummary.labels(routePath).observe(Number(end - start) / 1e9);
+			});
 			next();
 		});
 		app.use(compression());

packages/master/src/metrics.js

@@ -1,9 +1,14 @@
 // Shared metrics
 "use strict";
 const libPrometheus = require("@clusterio/lib/prometheus");
+const util = require("util");
 
 exports.endpointHitCounter = new libPrometheus.Counter(
 	"clusterio_master_http_endpoint_hits_total",
 	"How many requests a particular HTTP endpoint has gotten",
-	{ labels: ["route"] }
+	{ labels: ["route"], register: false }
+);
+
+exports.endpointHitCounter.labels = util.deprecate(
+	exports.endpointHitCounter.labels, "incrementing endpointHitCounter is no longer needed and has no effect"
 );

packages/master/src/routes.js

@@ -19,8 +19,6 @@ const libPlugin = require("@clusterio/lib/plugin");
 const libPrometheus = require("@clusterio/lib/prometheus");
 const { logger } = require("@clusterio/lib/logging");
 
-const { endpointHitCounter } = require("./metrics");
-
 const finished = util.promisify(nodeStream.finished);
 
 
@@ -41,8 +39,6 @@ function mergeSamples(destinationResult, sourceResult) {
 
 // Prometheus polling endpoint
 async function getMetrics(req, res, next) {
-	endpointHitCounter.labels(req.route.path).inc();
-
 	let results = [];
 	let pluginResults = await libPlugin.invokeHook(req.app.locals.master.plugins, "onMetrics");
 	for (let metricIterator of pluginResults) {
@@ -181,7 +177,6 @@ function validateUserToken(req, res, next) {
 
 // Handle an uploaded export package.
 async function uploadExport(req, res) {
-	endpointHitCounter.labels(req.route.path).inc();
 	if (req.get("Content-Type") !== "application/zip") {
 		res.sendStatus(415);
 		return;
@@ -340,7 +335,6 @@ async function uploadSave(req, res) {
 		res.status(403).json({ request_errors: [err.message] });
 		return;
 	}
-	endpointHitCounter.labels(req.route.path).inc();
 
 	let contentType = req.get("Content-Type");
 	let match = contentTypeRegExp.exec(contentType);
@@ -479,7 +473,6 @@ async function uploadMod(req, res) {
 		res.status(403).json({ request_errors: [err.message] });
 		return;
 	}
-	endpointHitCounter.labels(req.route.path).inc();
 
 	let contentType = req.get("Content-Type");
 	let match = contentTypeRegExp.exec(contentType);

plugins/player_auth/master.js

@@ -44,8 +44,6 @@ class MasterPlugin extends libPlugin.BaseMasterPlugin {
 		}, 60e3).unref();
 
 		this.master.app.get("/api/player_auth/servers", (req, res) => {
-			this.metrics.endpointHitCounter.labels(req.route.path).inc();
-
 			let servers = [];
 			for (let instance of this.master.instances.values()) {
 				if (instance.status === "running" && instance.config.get("player_auth.load_plugin")) {
@@ -56,12 +54,10 @@ class MasterPlugin extends libPlugin.BaseMasterPlugin {
 		});
 
 		this.master.app.post("/api/player_auth/player_code", express.json(), (req, res, next) => {
-			this.metrics.endpointHitCounter.labels(req.route.path).inc();
 			this.handlePlayerCode(req, res).catch(next);
 		});
 
 		this.master.app.post("/api/player_auth/verify", express.json(), (req, res, next) => {
-			this.metrics.endpointHitCounter.labels(req.route.path).inc();
 			this.handleVerify(req, res).catch(next);
 		});
 	}

plugins/subspace_storage/master.js

@@ -86,7 +86,7 @@ class MasterPlugin extends libPlugin.BaseMasterPlugin {
 
 		this.subscribedControlLinks = new Set();
 
-		routes.addApiRoutes(this.master.app, this.items, this.metrics.endpointHitCounter);
+		routes.addApiRoutes(this.master.app, this.items);
 	}
 
 	updateStorage() {

plugins/subspace_storage/routes.js

@@ -1,5 +1,5 @@
 "use strict";
-function addApiRoutes(app, items, endpointHitCounter) {
+function addApiRoutes(app, items) {
 
 	/**
 	 * GET endpoint to read the masters current inventory of items.
@@ -10,7 +10,6 @@ function addApiRoutes(app, items, endpointHitCounter) {
 	 * @returns {object[]} JSON [{name:"iron-plate", count:100},{name:"copper-plate",count:5}]
 	 */
 	app.get("/api/inventory", (req, res) => {
-		endpointHitCounter.labels(req.route.path).inc();
 		res.header("Access-Control-Allow-Origin", "*");
 		res.header("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept");
 		// Check it and send it
@@ -31,7 +30,6 @@ function addApiRoutes(app, items, endpointHitCounter) {
 	 * @returns {object} JSON {"iron-plate":100, "copper-plate":5}
 	 */
 	app.get("/api/inventoryAsObject", (req, res) => {
-		endpointHitCounter.labels(req.route.path).inc();
 		res.header("Access-Control-Allow-Origin", "*");
 		res.header("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept");
 		// Check it and send it

test/mock.js

@@ -219,9 +219,7 @@ class MockMaster {
 
 async function createMasterPlugin(MasterPluginClass, info) {
 	let master = new MockMaster();
-	let metrics = {
-		endpointHitCounter: new libPrometheus.Counter("hit_counter", "Hit Counter", { labels: ["route"] }),
-	};
+	let metrics = {};
 	let logger = new MockLogger();
 	let plugin = new MasterPluginClass(info, master, metrics, logger);
 	await plugin.init();