feat: metrics endpoint

server/app/data.yml

@@ -41,6 +41,8 @@ defaults:
       host: ''
       secure: true
       verifySSL: true
+    metrics:
+      isEnabled: false
     auth:
       autoLogin: false
       enforce2FA: false

server/controllers/common.mjs

@@ -434,6 +434,21 @@ export default function () {
     return res.sendStatus(404)
   })
 
+  /**
+   * Metrics (Prometheus)
+   */
+  router.get('/metrics', async (req, res, next) => {
+    if (!WIKI.auth.checkAccess(req.user, ['read:metrics'])) {
+      return res.sendStatus(403)
+    }
+
+    if (WIKI.config.metrics.isEnabled) {
+      WIKI.metrics.render(res)
+    } else {
+      next()
+    }
+  })
+
   // /**
   //  * View document / asset
   //  */

server/core/kernel.mjs

@@ -7,6 +7,7 @@ import db from './db.mjs'
 import extensions from './extensions.mjs'
 import scheduler from './scheduler.mjs'
 import servers from './servers.mjs'
+import metrics from './metrics.mjs'
 
 let isShuttingDown = false
 
@@ -47,6 +48,7 @@ export default {
       }
       WIKI.extensions = extensions
       WIKI.asar = asar
+      WIKI.metrics = await metrics.init()
     } catch (err) {
       WIKI.logger.error(err)
       process.exit(1)

server/core/metrics.mjs

@@ -0,0 +1,66 @@
+import { collectDefaultMetrics, register, Gauge } from 'prom-client'
+import { toSafeInteger } from 'lodash-es'
+
+export default {
+  customMetrics: {},
+  async init () {
+    if (WIKI.config.metrics.isEnabled) {
+      WIKI.logger.info('Initializing metrics...')
+
+      register.setDefaultLabels({
+        WIKI_INSTANCE: WIKI.INSTANCE_ID
+      })
+
+      collectDefaultMetrics()
+
+      this.customMetrics.groupsTotal = new Gauge({
+        name: 'wiki_groups_total',
+        help: 'Total number of groups',
+        async collect() {
+          const total = await WIKI.db.groups.query().count('* as total').first()
+          this.set(toSafeInteger(total.total))
+        }
+      })
+
+      this.customMetrics.pagesTotal = new Gauge({
+        name: 'wiki_pages_total',
+        help: 'Total number of pages',
+        async collect() {
+          const total = await WIKI.db.pages.query().count('* as total').first()
+          this.set(toSafeInteger(total.total))
+        }
+      })
+
+      this.customMetrics.tagsTotal = new Gauge({
+        name: 'wiki_tags_total',
+        help: 'Total number of tags',
+        async collect() {
+          const total = await WIKI.db.tags.query().count('* as total').first()
+          this.set(toSafeInteger(total.total))
+        }
+      })
+
+      this.customMetrics.usersTotal = new Gauge({
+        name: 'wiki_users_total',
+        help: 'Total number of users',
+        async collect() {
+          const total = await WIKI.db.users.query().count('* as total').first()
+          this.set(toSafeInteger(total.total))
+        }
+      })
+      WIKI.logger.info('Metrics ready [ OK ]')
+    } else {
+      this.customMetrics = {}
+      register.clear()
+    }
+    return this
+  },
+  async render (res) {
+    try {
+      res.contentType(register.contentType)
+      res.send(await register.metrics())
+    } catch (err) {
+      res.status(500).end(err.message)
+    }
+  }
+}

server/db/migrations/3.0.0.mjs

@@ -457,6 +457,12 @@ export async function up (knex) {
   })
 
   await knex('settings').insert([
+    {
+      key: 'api',
+      value: {
+        isEnabled: false
+      }
+    },
     {
       key: 'auth',
       value: {
@@ -516,6 +522,12 @@ export async function up (knex) {
         dkimPrivateKey: ''
       }
     },
+    {
+      key: 'metrics',
+      value: {
+        isEnabled: false
+      }
+    },
     {
       key: 'search',
       value: {

server/graph/resolvers/system.mjs

@@ -12,6 +12,12 @@ const getos = util.promisify(getosSync)
 
 export default {
   Query: {
+    /**
+     * Metrics Endpoint State
+     */
+    metricsState () {
+      return WIKI.config.metrics?.isEnabled ?? false
+    },
     /**
      * System Flags
      */
@@ -281,6 +287,24 @@ export default {
         return generateError(err)
       }
     },
+    /**
+     * Set Metrics endpoint state
+     */
+    async setMetricsState (obj, args, context) {
+      try {
+        if (!WIKI.auth.checkAccess(context.req.user, ['manage:system'])) {
+          throw new Error('ERR_FORBIDDEN')
+        }
+
+        WIKI.config.metrics.isEnabled = args.enabled
+        await WIKI.configSvc.saveToDb(['metrics'])
+        return {
+          operation: generateSuccess('Metrics endpoint state changed successfully')
+        }
+      } catch (err) {
+        return generateError(err)
+      }
+    },
     async updateSystemFlags (obj, args, context) {
       try {
         if (!WIKI.auth.checkAccess(context.req.user, ['manage:system'])) {

server/graph/schemas/system.graphql

@@ -3,6 +3,7 @@
 # ===============================================
 
 extend type Query {
+  metricsState: Boolean
   systemExtensions: [SystemExtension]
   systemFlags: JSON
   systemInfo: SystemInfo
@@ -35,6 +36,10 @@ extend type Mutation {
     id: UUID!
   ): DefaultResponse
 
+  setMetricsState(
+    enabled: Boolean!
+  ): DefaultResponse
+
   updateSystemSearch(
     termHighlighting: Boolean
     dictOverrides: String

server/locales/en.json

@@ -466,6 +466,16 @@
   "admin.mail.testRecipientHint": "Email address that should receive the test email.",
   "admin.mail.testSend": "Send Email",
   "admin.mail.title": "Mail",
+  "admin.metrics.auth": "You must provide the {headerName} header with a {tokenType} token. Generate an API key with the {permission} permission and use it as the token.",
+  "admin.metrics.disabled": "Endpoint Disabled",
+  "admin.metrics.enabled": "Endpoint Enabled",
+  "admin.metrics.endpoint": "The metrics endpoint can be scraped at {endpoint}",
+  "admin.metrics.endpointWarning": "Note that this override any page at this path.",
+  "admin.metrics.refreshSuccess": "Metrics endpoint state has been refreshed.",
+  "admin.metrics.subtitle": "Manage the Prometheus metrics endpoint",
+  "admin.metrics.title": "Metrics",
+  "admin.metrics.toggleStateDisabledSuccess": "Metrics endpoint disabled successfully.",
+  "admin.metrics.toggleStateEnabledSuccess": "Metrics endpoint enabled successfully.",
   "admin.nav.modules": "Modules",
   "admin.nav.site": "Site",
   "admin.nav.system": "System",

server/package.json

@@ -149,6 +149,7 @@
     "pg-query-stream": "4.5.3",
     "pg-tsquery": "8.4.1",
     "poolifier": "2.7.5",
+    "prom-client": "15.0.0",
     "punycode": "2.3.0",
     "puppeteer-core": "21.4.0",
     "qr-image": "3.2.0",

ux/src/layouts/AdminLayout.vue

@@ -181,6 +181,12 @@ q-layout.admin(view='hHh Lpr lff')
             q-item-section {{ t('admin.mail.title') }}
             q-item-section(side)
               status-light(:color='adminStore.info.isMailConfigured ? `positive` : `warning`', :pulse='!adminStore.info.isMailConfigured')
+          q-item(to='/_admin/metrics', v-ripple, active-class='bg-primary text-white')
+            q-item-section(avatar)
+              q-icon(name='img:/_assets/icons/fluent-graph.svg')
+            q-item-section {{ t('admin.metrics.title') }}
+            q-item-section(side)
+              status-light(:color='adminStore.info.isMetricsEnabled ? `positive` : `negative`')
           q-item(to='/_admin/rendering', v-ripple, active-class='bg-primary text-white')
             q-item-section(avatar)
               q-icon(name='img:/_assets/icons/fluent-rich-text-converter.svg')