From 5847724474b9a1d94679e347ca2c24d2b10d0b20 Mon Sep 17 00:00:00 2001
From: Chocobozzz <me@florianbigard.com>
Date: Thu, 5 Jan 2023 10:19:51 +0100
Subject: [PATCH] Add tracker opentelemtry metrics

---
 server.ts                                     |  5 +-
 server/controllers/tracker.ts                 |  2 +-
 .../bittorrent-tracker-observers-builder.ts   | 51 +++++++++++++++++++
 .../lib/opentelemetry/metric-helpers/index.ts |  1 +
 server/lib/opentelemetry/metrics.ts           |  6 ++-
 5 files changed, 61 insertions(+), 4 deletions(-)
 create mode 100644 server/lib/opentelemetry/metric-helpers/bittorrent-tracker-observers-builder.ts

diff --git a/server.ts b/server.ts
index dd595e951..f6a153fb7 100644
--- a/server.ts
+++ b/server.ts
@@ -279,7 +279,7 @@ app.use((err, _req, res: express.Response, _next) => {
   })
 })
 
-const server = createWebsocketTrackerServer(app)
+const { server, trackerServer } = createWebsocketTrackerServer(app)
 
 // ----------- Run -----------
 
@@ -328,7 +328,8 @@ async function startApplication () {
   VideoChannelSyncLatestScheduler.Instance.enable()
   VideoViewsBufferScheduler.Instance.enable()
   GeoIPUpdateScheduler.Instance.enable()
-  OpenTelemetryMetrics.Instance.registerMetrics()
+
+  OpenTelemetryMetrics.Instance.registerMetrics({ trackerServer })
 
   PluginManager.Instance.init(server)
   // Before PeerTubeSocket init
diff --git a/server/controllers/tracker.ts b/server/controllers/tracker.ts
index 0ef98c35e..c4f3a8889 100644
--- a/server/controllers/tracker.ts
+++ b/server/controllers/tracker.ts
@@ -121,7 +121,7 @@ function createWebsocketTrackerServer (app: express.Application) {
     // Don't destroy socket, we have Socket.IO too
   })
 
-  return server
+  return { server, trackerServer }
 }
 
 // ---------------------------------------------------------------------------
diff --git a/server/lib/opentelemetry/metric-helpers/bittorrent-tracker-observers-builder.ts b/server/lib/opentelemetry/metric-helpers/bittorrent-tracker-observers-builder.ts
new file mode 100644
index 000000000..ef40c0fa9
--- /dev/null
+++ b/server/lib/opentelemetry/metric-helpers/bittorrent-tracker-observers-builder.ts
@@ -0,0 +1,51 @@
+import { Meter } from '@opentelemetry/api'
+
+export class BittorrentTrackerObserversBuilder {
+
+  constructor (private readonly meter: Meter, private readonly trackerServer: any) {
+
+  }
+
+  buildObservers () {
+    const activeInfohashes = this.meter.createObservableGauge('peertube_bittorrent_tracker_active_infohashes_total', {
+      description: 'Total active infohashes in the PeerTube BitTorrent Tracker'
+    })
+    const inactiveInfohashes = this.meter.createObservableGauge('peertube_bittorrent_tracker_inactive_infohashes_total', {
+      description: 'Total inactive infohashes in the PeerTube BitTorrent Tracker'
+    })
+    const peers = this.meter.createObservableGauge('peertube_bittorrent_tracker_peers_total', {
+      description: 'Total peers in the PeerTube BitTorrent Tracker'
+    })
+
+    this.meter.addBatchObservableCallback(observableResult => {
+      const infohashes = Object.keys(this.trackerServer.torrents)
+
+      const counters = {
+        activeInfohashes: 0,
+        inactiveInfohashes: 0,
+        peers: 0,
+        uncompletedPeers: 0
+      }
+
+      for (const infohash of infohashes) {
+        const content = this.trackerServer.torrents[infohash]
+
+        const peers = content.peers
+        if (peers.keys.length !== 0) counters.activeInfohashes++
+        else counters.inactiveInfohashes++
+
+        for (const peerId of peers.keys) {
+          const peer = peers.peek(peerId)
+          if (peer == null) return
+
+          counters.peers++
+        }
+      }
+
+      observableResult.observe(activeInfohashes, counters.activeInfohashes)
+      observableResult.observe(inactiveInfohashes, counters.inactiveInfohashes)
+      observableResult.observe(peers, counters.peers)
+    }, [ activeInfohashes, inactiveInfohashes, peers ])
+  }
+
+}
diff --git a/server/lib/opentelemetry/metric-helpers/index.ts b/server/lib/opentelemetry/metric-helpers/index.ts
index 775d954ba..47b24a54f 100644
--- a/server/lib/opentelemetry/metric-helpers/index.ts
+++ b/server/lib/opentelemetry/metric-helpers/index.ts
@@ -1,3 +1,4 @@
+export * from './bittorrent-tracker-observers-builder'
 export * from './lives-observers-builder'
 export * from './job-queue-observers-builder'
 export * from './nodejs-observers-builder'
diff --git a/server/lib/opentelemetry/metrics.ts b/server/lib/opentelemetry/metrics.ts
index 226d514c0..9cc067e4a 100644
--- a/server/lib/opentelemetry/metrics.ts
+++ b/server/lib/opentelemetry/metrics.ts
@@ -7,6 +7,7 @@ import { CONFIG } from '@server/initializers/config'
 import { MVideoImmutable } from '@server/types/models'
 import { PlaybackMetricCreate } from '@shared/models'
 import {
+  BittorrentTrackerObserversBuilder,
   JobQueueObserversBuilder,
   LivesObserversBuilder,
   NodeJSObserversBuilder,
@@ -41,7 +42,7 @@ class OpenTelemetryMetrics {
     })
   }
 
-  registerMetrics () {
+  registerMetrics (options: { trackerServer: any }) {
     if (CONFIG.OPEN_TELEMETRY.METRICS.ENABLED !== true) return
 
     logger.info('Registering Open Telemetry metrics')
@@ -80,6 +81,9 @@ class OpenTelemetryMetrics {
 
     const viewersObserversBuilder = new ViewersObserversBuilder(this.meter)
     viewersObserversBuilder.buildObservers()
+
+    const bittorrentTrackerObserversBuilder = new BittorrentTrackerObserversBuilder(this.meter, options.trackerServer)
+    bittorrentTrackerObserversBuilder.buildObservers()
   }
 
   observePlaybackMetric (video: MVideoImmutable, metrics: PlaybackMetricCreate) {
-- 
2.41.0