1 files changed, 151 insertions, 0 deletions
diff --git a/nixos/modules/services/monitoring/metricbeat.nix b/nixos/modules/services/monitoring/metricbeat.nix
new file mode 100644
index 00000000000..e75039daa10
--- /dev/null
+++ b/nixos/modules/services/monitoring/metricbeat.nix
@@ -0,0 +1,151 @@
+{ config, lib, pkgs, ... }:
+
+let
+  inherit (lib)
+    attrValues
+    literalExpression
+    mkEnableOption
+    mkIf
+    mkOption
+    types
+    ;
+  cfg = config.services.metricbeat;
+
+  settingsFormat = pkgs.formats.yaml {};
+
+in
+{
+  options = {
+
+    services.metricbeat = {
+
+      enable = mkEnableOption "metricbeat";
+
+      package = mkOption {
+        type = types.package;
+        default = pkgs.metricbeat;
+        defaultText = literalExpression "pkgs.metricbeat";
+        example = literalExpression "pkgs.metricbeat7";
+        description = ''
+          The metricbeat package to use
+        '';
+      };
+
+      modules = mkOption {
+        description = ''
+          Metricbeat modules are responsible for reading metrics from the various sources.
+
+          This is like <literal>services.metricbeat.settings.metricbeat.modules</literal>,
+          but structured as an attribute set. This has the benefit that multiple
+          NixOS modules can contribute settings to a single metricbeat module.
+
+          A module can be specified multiple times by choosing a different <literal>&lt;name></literal>
+          for each, but setting <xref linkend="opt-services.metricbeat.modules._name_.module"/> to the same value.
+
+          See <link xlink:href="https://www.elastic.co/guide/en/beats/metricbeat/current/metricbeat-modules.html"/>.
+        '';
+        default = {};
+        type = types.attrsOf (types.submodule ({ name, ... }: {
+          freeformType = settingsFormat.type;
+          options = {
+            module = mkOption {
+              type = types.str;
+              default = name;
+              description = ''
+                The name of the module.
+
+                Look for the value after <literal>module:</literal> on the individual
+                module pages linked from <link xlink:href="https://www.elastic.co/guide/en/beats/metricbeat/current/metricbeat-modules.html"/>.
+              '';
+            };
+          };
+        }));
+        example = {
+          system = {
+            metricsets = ["cpu" "load" "memory" "network" "process" "process_summary" "uptime" "socket_summary"];
+            enabled = true;
+            period = "10s";
+            processes = [".*"];
+            cpu.metrics = ["percentages" "normalized_percentages"];
+            core.metrics = ["percentages"];
+          };
+        };
+      };
+
+      settings = mkOption {
+        type = types.submodule {
+          freeformType = settingsFormat.type;
+          options = {
+
+            name = mkOption {
+              type = types.str;
+              default = "";
+              description = ''
+                Name of the beat. Defaults to the hostname.
+                See <link xlink:href="https://www.elastic.co/guide/en/beats/metricbeat/current/configuration-general-options.html#_name"/>.
+              '';
+            };
+
+            tags = mkOption {
+              type = types.listOf types.str;
+              default = [];
+              description = ''
+                Tags to place on the shipped metrics.
+                See <link xlink:href="https://www.elastic.co/guide/en/beats/metricbeat/current/configuration-general-options.html#_tags_2"/>.
+              '';
+            };
+
+            metricbeat.modules = mkOption {
+              type = types.listOf settingsFormat.type;
+              default = [];
+              internal = true;
+              description = ''
+                The metric collecting modules. Use <xref linkend="opt-services.metricbeat.modules"/> instead.
+
+                See <link xlink:href="https://www.elastic.co/guide/en/beats/metricbeat/current/metricbeat-modules.html"/>.
+              '';
+            };
+          };
+        };
+        default = {};
+        description = ''
+          Configuration for metricbeat. See <link xlink:href="https://www.elastic.co/guide/en/beats/metricbeat/current/configuring-howto-metricbeat.html"/> for supported values.
+        '';
+      };
+
+    };
+  };
+
+  config = mkIf cfg.enable {
+
+    assertions = [
+      {
+        # empty modules would cause a failure at runtime
+        assertion = cfg.settings.metricbeat.modules != [];
+        message = "services.metricbeat: You must configure one or more modules.";
+      }
+    ];
+
+    services.metricbeat.settings.metricbeat.modules = attrValues cfg.modules;
+
+    systemd.services.metricbeat = {
+      description = "metricbeat metrics shipper";
+      wantedBy = [ "multi-user.target" ];
+      serviceConfig = {
+        ExecStart = ''
+          ${cfg.package}/bin/metricbeat \
+            -c ${settingsFormat.generate "metricbeat.yml" cfg.settings} \
+            --path.data $STATE_DIRECTORY \
+            --path.logs $LOGS_DIRECTORY \
+            ;
+        '';
+        Restart = "always";
+        DynamicUser = true;
+        ProtectSystem = "strict";
+        ProtectHome = "tmpfs";
+        StateDirectory = "metricbeat";
+        LogsDirectory = "metricbeat";
+      };
+    };
+  };
+}