From a868fd0698666feb4e1b3b7609615ced0b00e6df Mon Sep 17 00:00:00 2001
From: Samuel Hernandez <sam@samhza.com>
Date: Sun, 2 May 2021 16:16:48 -0400
Subject: [PATCH 1/2] Add serving metrics for Prometheus

Co-authored-by: TheEssem <smswessem@gmail.com>
---
 .env.example |  4 +++-
 shard.js     | 41 ++++++++++++++++++++++++++++++++++++++---
 2 files changed, 41 insertions(+), 4 deletions(-)

diff --git a/.env.example b/.env.example
index 967e517..3f9991c 100644
--- a/.env.example
+++ b/.env.example
@@ -44,8 +44,10 @@ OUTPUT=
 TEMPDIR=
 # Put temporary image web server domain
 TMP_DOMAIN=
+# Port for serving metrics. Metrics served are compatible with Prometheus.
+METRICS=
 
 # Set this to true if you're using PM2 to manage the bot
 PMTWO=false
 # Set this to true if you want to use the image API
-API=false
\ No newline at end of file
+API=false
diff --git a/shard.js b/shard.js
index 689b000..75e3dba 100644
--- a/shard.js
+++ b/shard.js
@@ -21,6 +21,7 @@ const misc = require("./utils/misc.js");
 // generate help page
 const helpGenerator =
   process.env.OUTPUT !== "" ? require("./utils/help.js") : null;
+const http = require("http");
 
 class Shard extends Base {
   constructor(bot) {
@@ -39,7 +40,7 @@ class Shard extends Base {
         logger.error(`Failed to register command from ${commandFile}: ${e}`);
       }
     }
-  
+
     // register events
     const events = await readdir("./events/");
     logger.log("info", `Attempting to load ${events.length} events...`);
@@ -49,7 +50,7 @@ class Shard extends Base {
       const event = require(`./events/${file}`);
       this.bot.on(eventName, event.bind(null, this.bot, this.clusterID, this.ipc));
     }
-  
+
     // connect to image api if enabled
     if (process.env.API === "true") {
       for (const server of image.servers) {
@@ -68,6 +69,40 @@ class Shard extends Base {
       logger.log("info", "The help docs have been generated.");
     }
 
+    if (process.env.METRICS !== "") {
+      logger.log("YES");
+      const httpServer = http.createServer((req, res) => {
+        if (req.method !== "GET") {
+          res.statusCode = 405;
+          return res.end("GET only");
+        }
+        res.write(`# HELP connected_workers Number of workers connected
+# TYPE connected_workers guage
+connected_workers ${image.connections.length}
+# HELP running_jobs Number of running jobs on this worker
+# TYPE running_jobs guage
+# HELP queued_jobs Number of queued jobs on this worker
+# TYPE queued_jobs guage
+# HELP max_jobs Number of max allowed jobs on this worker
+# TYPE max_jobs guage
+`);
+        image.getStatus().then((servers) => {
+          for (const [i, w] of servers.entries()) {
+            res.write(`running_jobs{worker="${i}} ${w.runningJobs}\n`);
+            res.write(`queued_jobs{worker="${i}} ${w.queued}\n`);
+            res.write(`max_jobs{worker="${i}} ${w.max}\n`);
+          }
+          res.end();
+        }).catch(e => {
+          res.statusCode = 500;
+          return res.end(e);
+        });
+      });
+      httpServer.listen(process.env.METRICS, () => {
+        logger.log("info", `Serving metrics at ${process.env.METRICS}`);
+      });
+    }
+
     // handle process stop
     process.on("SIGINT", () => {
       logger.log("warn", "SIGINT detected, shutting down...");
@@ -139,4 +174,4 @@ class Shard extends Base {
 
 }
 
-module.exports = Shard;
\ No newline at end of file
+module.exports = Shard;

From dd748fbc6094a8fe57e215fbf2d5d929658925ac Mon Sep 17 00:00:00 2001
From: TheEssem <smswessem@gmail.com>
Date: Mon, 3 May 2021 08:30:07 -0500
Subject: [PATCH 2/2] just some fixes

---
 shard.js | 28 ++++++++++++----------------
 1 file changed, 12 insertions(+), 16 deletions(-)

diff --git a/shard.js b/shard.js
index 75e3dba..0ce1c5c 100644
--- a/shard.js
+++ b/shard.js
@@ -71,32 +71,28 @@ class Shard extends Base {
 
     if (process.env.METRICS !== "") {
       logger.log("YES");
-      const httpServer = http.createServer((req, res) => {
+      const httpServer = http.createServer(async (req, res) => {
         if (req.method !== "GET") {
           res.statusCode = 405;
           return res.end("GET only");
         }
         res.write(`# HELP connected_workers Number of workers connected
-# TYPE connected_workers guage
+# TYPE connected_workers gauge
 connected_workers ${image.connections.length}
 # HELP running_jobs Number of running jobs on this worker
-# TYPE running_jobs guage
+# TYPE running_jobs gauge
 # HELP queued_jobs Number of queued jobs on this worker
-# TYPE queued_jobs guage
+# TYPE queued_jobs gauge
 # HELP max_jobs Number of max allowed jobs on this worker
-# TYPE max_jobs guage
+# TYPE max_jobs gauge
 `);
-        image.getStatus().then((servers) => {
-          for (const [i, w] of servers.entries()) {
-            res.write(`running_jobs{worker="${i}} ${w.runningJobs}\n`);
-            res.write(`queued_jobs{worker="${i}} ${w.queued}\n`);
-            res.write(`max_jobs{worker="${i}} ${w.max}\n`);
-          }
-          res.end();
-        }).catch(e => {
-          res.statusCode = 500;
-          return res.end(e);
-        });
+        const servers = await image.getStatus();
+        for (const [i, w] of servers.entries()) {
+          res.write(`running_jobs{worker="${i}"} ${w.runningJobs}\n`);
+          res.write(`queued_jobs{worker="${i}"} ${w.queued}\n`);
+          res.write(`max_jobs{worker="${i}"} ${w.max}\n`);
+        }
+        res.end();
       });
       httpServer.listen(process.env.METRICS, () => {
         logger.log("info", `Serving metrics at ${process.env.METRICS}`);