From ad91208ae1cea92566ad03d3b4cdd68f0e71c55a Mon Sep 17 00:00:00 2001
From: Max Audron <audron@cocaine.farm>
Date: Fri, 1 Aug 2025 02:01:20 +0200
Subject: add minecraft prometheus exporter

---
 lib/monitoring/default.nix                     |  8 ++++++
 modules/games/default.nix                      | 35 +++++++++++++++++++++++---
 modules/monitoring/default.nix                 |  2 ++
 pkgs/prometheus-minecraft-exporter/default.nix | 24 ++++++++++++++++++
 pkgs/prometheus-minecraft-exporter/result      |  1 +
 secrets                                        |  2 +-
 6 files changed, 68 insertions(+), 4 deletions(-)
 create mode 100644 pkgs/prometheus-minecraft-exporter/default.nix
 create mode 120000 pkgs/prometheus-minecraft-exporter/result

diff --git a/lib/monitoring/default.nix b/lib/monitoring/default.nix
index 2c7c3cf..b06c9f7 100644
--- a/lib/monitoring/default.nix
+++ b/lib/monitoring/default.nix
@@ -11,6 +11,14 @@ rec {
     relabel_configs = relabelConfig;
   };
 
+  mkScrape = name: targets: {
+    job_name = name; 
+    static_configs = [{
+      targets = targets;
+    }]; 
+    relabel_configs = relabelConfig;
+  };
+
   relabelConfig = [{
     source_labels = ["__address__"];
     target_label = "host";
diff --git a/modules/games/default.nix b/modules/games/default.nix
index fee8e34..8befc83 100644
--- a/modules/games/default.nix
+++ b/modules/games/default.nix
@@ -55,6 +55,7 @@
     minecraft_mods = {
       image = "itzg/minecraft-server";
       autoStart = true;
+      extraOptions = [ "--network=host" ];
       environment = {
         EULA = "true";
         TYPE = "FABRIC";
@@ -62,15 +63,43 @@
         SEED = "-3691007458655063350";
         INIT_MEMORY = "1G";
         MAX_MEMORY = "4G";
+
+        OVERRIDE_SERVER_PROPERTIES = "false";
       };
-      ports = [
-        "25566:25565"
-      ];
       volumes = [
         "/var/lib/minecraft_mods:/data"
       ];
     };
   };
 
+  systemd.services.prometheus-minecraft-exporter = 
+    let exporter = pkgs.callPackage ../../pkgs/prometheus-minecraft-exporter {};
+  in {
+    description = "minecraft prometheus exporter";
+    enable = true;
+
+    wantedBy = [ "multi-user.target" ];
+    after = [ "network.target" "podman-minecraft_mods.service" ];
+
+    serviceConfig = {
+      ExecStart = (lib.concatStringsSep " " ([
+        "${exporter}/bin/minecraft-exporter"
+        "--web.listen-address=:9150"
+        "--mc.world=/var/lib/minecraft_mods/world"
+        "--mc.name-source=mojang"
+        "--mc.mod-server-stats=fabric"
+        "--web.disable-exporter-metrics"
+      ]));
+      EnvironmentFile = "/etc/secrets/minecraft_rcon.env";
+    };
+  };
+
+  secrets = {
+    minecraft = {
+      source = ../../secrets/minecraft_rcon.env;
+      dest = "/etc/secrets/minecraft_rcon.env";
+    };
+  };
+
   networking.firewall.allowedTCPPorts = [ 25566 ];
 }
diff --git a/modules/monitoring/default.nix b/modules/monitoring/default.nix
index afcffa5..fe49c00 100644
--- a/modules/monitoring/default.nix
+++ b/modules/monitoring/default.nix
@@ -35,6 +35,8 @@ in {
       
       (mkScrapeConfig "garage" [ "fra01" "nyc01" "sin01" ] 3903)
       (mkScrapeConfig "pdns" [ "ettves" "fra01" "nyc01" "sin01" ] 8081)
+      
+      (mkScrape "minecraft" [ "ettves:25585" "ettves:9150" ])
     ];
   };
 
diff --git a/pkgs/prometheus-minecraft-exporter/default.nix b/pkgs/prometheus-minecraft-exporter/default.nix
new file mode 100644
index 0000000..396f092
--- /dev/null
+++ b/pkgs/prometheus-minecraft-exporter/default.nix
@@ -0,0 +1,24 @@
+{ lib, 
+  buildGoModule,
+  fetchFromGitHub,
+  ...
+}:
+
+buildGoModule {
+  pname = "prometheus-minecraft-exporter";
+  version = "0.22.0";
+
+  src = fetchFromGitHub {
+    owner = "dirien";
+    repo = "minecraft-prometheus-exporter";
+    rev = "v0.22.0";
+    hash = "sha256-jjdFbGyK+bHgZx/UAbBygCnY/9f9QxgHGqxUusR7ro8=";
+  };
+
+  vendorHash = "sha256-Smlkqig7UVTSOrBGhEExbqefqh3Gv3LWbNOUdpJhLtQ=";
+
+  meta = {
+    description = "collect player metrics from a minecraft server";
+    homepage = "https://github.com/dirien/minecraft-prometheus-exporter";
+  };
+}
diff --git a/pkgs/prometheus-minecraft-exporter/result b/pkgs/prometheus-minecraft-exporter/result
new file mode 120000
index 0000000..1724469
--- /dev/null
+++ b/pkgs/prometheus-minecraft-exporter/result
@@ -0,0 +1 @@
+/nix/store/kic17804i3jz88k1r4vd9mwnwlyji247-prometheus-minecraft-exporter-0.22.0
\ No newline at end of file
diff --git a/secrets b/secrets
index 25b1d46..10079a5 160000
--- a/secrets
+++ b/secrets
@@ -1 +1 @@
-Subproject commit 25b1d46edbbd5c9faad93c40ddfad9696b9e3cc9
+Subproject commit 10079a53596523af7c8294e73e688b87ba1513e5
-- 
cgit v1.2.3