Merge pull request 'prometheus' (#10) from prometheus into master

Reviewed-on: https://git.rz.ens.wtf/HackENS/hackens-org-configurations/pulls/10

hosts/hackens-org/modules/mqtt2prometheus/default.nix

@@ -0,0 +1,39 @@
+{ pkgs, lib, config, ... }:
+let
+  cfg = config.services.mqtt2prometheus;
+in
+{
+  options.services.mqtt2prometheus = {
+    enable = lib.mkEnableOption "Enable mqtt2Prometheus";
+    package = lib.mkOption {
+      type = lib.types.package;
+      description = "Which mqtt2prometheus package to use";
+    };
+    listenAddress = lib.mkOption {
+      type = lib.types.str;
+      default = "127.0.0.1";
+      description = "listen address for HTTP server used to expose metrics";
+    };
+    listenPort = lib.mkOption {
+      type = lib.types.port;
+      default = 9641;
+      description = "HTTP port used to expose metrics";
+    };
+    config = lib.mkOption { # à nixifier
+      type = lib.types.path;
+      description = "Path to config file";
+    };
+  };
+  config = lib.mkIf cfg.enable {
+    systemd.services."mqtt2prometheus" = {
+      enable = true;
+      description = "MQTT client which exposes metrics for prometheus monitoring software";
+      after = [ "network.target" ];
+      serviceConfig = {
+        ExecStart = "${cfg.package}/bin/mqtt2prometheus -config ${cfg.config} -listen-address ${cfg.listenAddress} -listen-port ${toString cfg.listenPort}";
+        Restart = "always";
+      };
+      wantedBy = [ "multi-user.target" ];
+    };
+  };
+}

hosts/hackens-org/modules/mqtt2prometheus/mqtt2prometheus.nix

@@ -0,0 +1,15 @@
+{ pkgs, ... }:
+pkgs.buildGoModule rec {
+  pname = "mqtt2prometheus";
+  version = "0.1.6";
+  src = pkgs.fetchFromGitHub {
+    owner = "hikhvar";
+    repo = "mqtt2prometheus";
+    rev = "v${version}";
+    sha256 = "0dz5mrwm231g45i8rbmvaza8bm6cr4jg5vc87h41vnm7xsx815g7";
+  };
+  vendorSha256 = "1fyzij7cakhd6x2hf3rvvslvvxmfmlp881x5rz2qwm04spa18cp4";
+  postInstall = ''
+    mv $out/bin/cmd $out/bin/mqtt2prometheus
+    '';
+}

hosts/hackens-org/prometheus/config.yaml

@@ -0,0 +1,23 @@
+mqtt:
+ # The MQTT broker to connect to
+ server: tcp://new.hackens.org:1883
+ # The Topic path to subscribe to. Be aware that you have to specify the wildcard, if you want to follow topics for multiple sensors.
+ topic_path: kfet/open
+ # The MQTT QoS level
+ qos: 0
+ metric_per_topic_config:
+  metric_name_regex: "(?P<deviceid>.*)/(?P<metricname>.*)"
+cache:
+ # Timeout. Each received metric will be presented for this time if no update is send via MQTT.
+ # Set the timeout to -1 to disable the deletion of metrics from the cache. The exporter presents the ingest timestamp
+ # to prometheus.
+ timeout: 24h
+metrics:
+ # The name of the metric in prometheus
+ - prom_name: keft_open
+  # The name of the metric in a MQTT JSON message
+   mqtt_name: open
+  # The prometheus help text for this metric
+   help: K-Fêt opening state
+  # The prometheus type for this metric. Valid values are: "gauge" and "counter"
+   type: gauge

hosts/hackens-org/prometheus/default.nix

@@ -0,0 +1,28 @@
+{ pkgs, lib, config, ... }:
+{
+  imports = [ ../modules/mqtt2prometheus ];
+  networking.firewall.allowedTCPPorts = [ 9090 ];
+  services = {
+    prometheus = {
+      enable = true;
+      scrapeConfigs = [
+        {
+          job_name = "mqtt_listener";
+          scrape_interval = "120s";
+          static_configs = [
+            {
+              targets = [
+                "localhost:9641"
+              ];
+            }
+          ];
+        }
+      ];
+    };
+    mqtt2prometheus = {
+      enable = true;
+      package = pkgs.callPackage (import ./mqtt2prometheus.nix) { };
+      config = ./config.yaml;
+    };
+  };
+}

hosts/hackens-org/prometheus/mqtt2prometheus.nix

@@ -0,0 +1,15 @@
+{ pkgs, ... }:
+pkgs.buildGoModule rec {
+  pname = "mqtt2prometheus";
+  version = "0.1.6";
+  src = pkgs.fetchFromGitHub {
+    owner = "hikhvar";
+    repo = "mqtt2prometheus";
+    rev = "v${version}";
+    sha256 = "0dz5mrwm231g45i8rbmvaza8bm6cr4jg5vc87h41vnm7xsx815g7";
+  };
+  vendorSha256 = "1fyzij7cakhd6x2hf3rvvslvvxmfmlp881x5rz2qwm04spa18cp4";
+  postInstall = ''
+    mv $out/bin/cmd $out/bin/mqtt2prometheus
+    '';
+}