chore: added prometheus support in Etherpad (#7095)

pnpm-lock.yaml

@@ -224,6 +224,9 @@ importers:
       openapi-backend:
         specifier: ^5.15.0
         version: 5.15.0
+      prom-client:
+        specifier: ^15.1.3
+        version: 15.1.3
       proxy-addr:
         specifier: ^2.0.7
         version: 2.0.7
@@ -832,6 +835,10 @@ packages:
     resolution: {integrity: sha512-nn5ozdjYQpUCZlWGuxcJY/KpxkWQs4DcbMCmKojjyrYDEAGy4Ce19NN4v5MduafTwJlbKc99UA8YhSVqq9yPZA==}
     engines: {node: '>=12.4.0'}
 
+  '@opentelemetry/api@1.9.0':
+    resolution: {integrity: sha512-3giAOQvZiH5F9bMlMiv8+GSPMeqg0dbaeo58/0SlA9sxSqZhnUtxzX9/2FzyhS9sWQf5S0GJE0AKBrFqjpeYcg==}
+    engines: {node: '>=8.0.0'}
+
   '@paralleldrive/cuid2@2.2.2':
     resolution: {integrity: sha512-ZOBkgDwEdoYVlSeRbYYXs0S9MejQofiVYoTbKzy/6GQa39/q5tQU2IX46+shYnUkpEl3wc+J6wRlar7r2EK2xA==}
 
@@ -2073,6 +2080,9 @@ packages:
   binary-search@1.3.6:
     resolution: {integrity: sha512-nbE1WxOTTrUWIfsfZ4aHGYu5DOuNkbxGokjV6Z2kxfJK3uaAb8zNK1muzOeipoLHZjInT4Br88BHpzevc681xA==}
 
+  bintrees@1.0.2:
+    resolution: {integrity: sha512-VOMgTMwjAaUG580SXn3LacVgjurrbMme7ZZNYGSSV7mmtY6QQRh0Eg3pwIcntQ77DErK1L0NxkbetjcoXzVwKw==}
+
   birpc@2.5.0:
     resolution: {integrity: sha512-VSWO/W6nNQdyP520F1mhf+Lc2f8pjGQOtoHHm7Ze8Go1kX7akpVIrtTa0fn+HB0QJEDVacl6aO08YE0PgXfdnQ==}
 
@@ -3825,6 +3835,10 @@ packages:
     resolution: {integrity: sha512-vkcDPrRZo1QZLbn5RLGPpg/WmIQ65qoWWhcGKf/b5eplkkarX0m9z8ppCat4mlOqUsWpyNuYgO3VRyrYHSzX5g==}
     engines: {node: '>= 0.8.0'}
 
+  prom-client@15.1.3:
+    resolution: {integrity: sha512-6ZiOBfCywsD4k1BN9IX0uZhF+tJkV8q8llP64G5Hajs4JOeVLPCwpPVcpXy3BwYiUGgyJzsJJQeOIv7+hDSq8g==}
+    engines: {node: ^16 || ^18 || >=20}
+
   promise@1.3.0:
     resolution: {integrity: sha512-R9WrbTF3EPkVtWjp7B7umQGVndpsi+rsDAfrR4xAALQpFLa/+2OriecLhawxzvii2gd9+DZFwROWDuUUaqS5yA==}
 
@@ -4376,6 +4390,9 @@ packages:
     resolution: {integrity: sha512-DZ4yORTwrbTj/7MZYq2w+/ZFdI6OZ/f9SFHR+71gIVUZhOQPHzVCLpvRnPgyaMpfWxxk/4ONva3GQSyNIKRv6A==}
     engines: {node: '>=10'}
 
+  tdigest@0.1.2:
+    resolution: {integrity: sha512-+G0LLgjjo9BZX2MfdvPfH+MKLCrxlXSYec5DaPYP1fe6Iyhf0/fSmJ0bFiZ1F8BT6cGXl2LpltQptzjXKWEkKA==}
+
   tinybench@2.9.0:
     resolution: {integrity: sha512-0+DUvqWMValLmha6lr4kD8iAMK1HzV0/aKnCtWb9v9641TnP/MFb7Pc2bxoxQjTXAErryXVgUOfv2YqNllqGeg==}
 
@@ -5252,6 +5269,8 @@ snapshots:
 
   '@nolyfill/is-core-module@1.0.39': {}
 
+  '@opentelemetry/api@1.9.0': {}
+
   '@paralleldrive/cuid2@2.2.2':
     dependencies:
       '@noble/hashes': 1.8.0
@@ -6491,6 +6510,8 @@ snapshots:
 
   binary-search@1.3.6: {}
 
+  bintrees@1.0.2: {}
+
   birpc@2.5.0: {}
 
   body-parser@2.2.0:
@@ -8499,6 +8520,11 @@ snapshots:
 
   prelude-ls@1.2.1: {}
 
+  prom-client@15.1.3:
+    dependencies:
+      '@opentelemetry/api': 1.9.0
+      tdigest: 0.1.2
+
   promise@1.3.0:
     dependencies:
       is-promise: 1.0.1
@@ -9141,6 +9167,10 @@ snapshots:
       mkdirp: 1.0.4
       yallist: 4.0.0
 
+  tdigest@0.1.2:
+    dependencies:
+      bintrees: 1.0.2
+
   tinybench@2.9.0: {}
 
   tinycon@0.6.8: {}

src/node/hooks/express/specialpages.ts

@@ -13,8 +13,11 @@ const plugins = require('../../../static/js/pluginfw/plugin_defs');
 
 import {build, buildSync} from 'esbuild'
 import {ArgsExpressType} from "../../types/ArgsExpressType";
+import prometheus from "../../prometheus";
+
 let ioI: { sockets: { sockets: any[]; }; } | null = null
 
+
 exports.socketio = (hookName: string, {io}: any) => {
   ioI = io
 }
@@ -35,6 +38,12 @@ exports.expressPreSession = async (hookName:string, {app}:ArgsExpressType) => {
     app.get('/stats', (req:any, res:any) => {
       res.json(require('../../stats').toJSON());
     });
+
+    app.get('/stats/prometheus', async (req, res) => {
+      const metrics = await prometheus()
+      res.setHeader('Content-Type', metrics.contentType)
+      res.send(await metrics.metrics())
+    })
   }
 
 

src/node/metrics.ts

@@ -0,0 +1,11 @@
+import Prometheus from 'prom-client';
+
+export const metrics = {
+  'cpu': new Prometheus.Gauge({ name: 'nodejs_cpu_gauge', help: 'gauge for nodejs cpu' ,labelNames: ['type'] }),
+  'memory_process': new Prometheus.Gauge({ name: 'nodejs_memory_process_gauge', help: 'gauge for nodejs memory_process' ,labelNames: ['type'] }),
+  'memory_physical': new Prometheus.Gauge({ name: 'nodejs_memory_physical_gauge', help: 'gauge for nodejs_memory_physical' ,labelNames: ['type'] }),
+  'eventloop_latency':  new Prometheus.Gauge({ name: 'nodejs_eventloop_latency_gauge' , help: 'gauge for nodejs_eventloop_latency' ,labelNames: ['type'] }),
+  'gc': new Prometheus.Gauge({ name: 'nodejs_gc_gauge' , help: 'gause for nodejs_gc' ,labelNames: ['type']}),
+  'gc_duration': new Prometheus.Summary({ name: 'nodejs_gc_duration' , help: 'gause for nodejs_gc_duration', percentiles: [ 0.5, 0.75, 0.95 ] }),
+  'http_duration': new Prometheus.Summary({ name: 'http_duration', help: 'summary for http_duration', percentiles: [ 0.5, 0.75, 0.95 ] ,labelNames: ['url'] })
+};

src/node/prometheus.ts

@@ -0,0 +1,25 @@
+import client from 'prom-client'
+const db = require('./db/DB').db
+
+const monitor = function () {
+  const collectDefaultMetrics = client.collectDefaultMetrics;
+  const Registry = client.Registry;
+  const register = new Registry();
+  collectDefaultMetrics({register});
+  const gaugeDB = new client.Gauge({
+    name: "ueberdb_stats",
+    help: "ueberdb stats",
+    labelNames: ['type'],
+  })
+
+  for (const [metric, value] of Object.entries(db.metrics)) {
+    if (typeof value !== 'number') continue;
+    gaugeDB.set({type: metric}, value);
+  }
+
+
+  register.registerMetric(gaugeDB);
+  return register
+};
+
+export default monitor;

src/package.json

@@ -58,6 +58,7 @@
     "mime-types": "^3.0.1",
     "oidc-provider": "^9.4.2",
     "openapi-backend": "^5.15.0",
+    "prom-client": "^15.1.3",
     "proxy-addr": "^2.0.7",
     "rate-limiter-flexible": "^7.2.0",
     "rehype": "^13.0.2",