From 707c3ac43589c1b13c16aa834f67b8fb49b8557d Mon Sep 17 00:00:00 2001
From: Peter Hoeg <peter@hoeg.com>
Date: Sun, 26 Feb 2017 10:52:30 +0800
Subject: [PATCH] sensu: nixos module

---
 nixos/modules/module-list.nix                 |   1 +
 .../services/monitoring/sensu/checks.nix      |  76 ++
 .../services/monitoring/sensu/client.nix      |  49 ++
 .../services/monitoring/sensu/dashboard.nix   | 112 +++
 .../services/monitoring/sensu/default.nix     | 710 ++++++++++++++++++
 .../services/monitoring/sensu/handlers.nix    |  70 ++
 .../monitoring/sensu/host_port_pair.nix       |  17 +
 .../services/monitoring/sensu/mutators.nix    |  17 +
 .../services/monitoring/sensu/plugins.nix     |  83 ++
 .../services/monitoring/sensu/sites.nix       |  59 ++
 10 files changed, 1194 insertions(+)
 create mode 100644 nixos/modules/services/monitoring/sensu/checks.nix
 create mode 100644 nixos/modules/services/monitoring/sensu/client.nix
 create mode 100644 nixos/modules/services/monitoring/sensu/dashboard.nix
 create mode 100644 nixos/modules/services/monitoring/sensu/default.nix
 create mode 100644 nixos/modules/services/monitoring/sensu/handlers.nix
 create mode 100644 nixos/modules/services/monitoring/sensu/host_port_pair.nix
 create mode 100644 nixos/modules/services/monitoring/sensu/mutators.nix
 create mode 100644 nixos/modules/services/monitoring/sensu/plugins.nix
 create mode 100644 nixos/modules/services/monitoring/sensu/sites.nix

diff --git a/nixos/modules/module-list.nix b/nixos/modules/module-list.nix
index 9cc3d73d2956..5e6b42dea543 100644
--- a/nixos/modules/module-list.nix
+++ b/nixos/modules/module-list.nix
@@ -379,6 +379,7 @@
   ./services/monitoring/riemann-dash.nix
   ./services/monitoring/riemann-tools.nix
   ./services/monitoring/scollector.nix
+  ./services/monitoring/sensu/default.nix
   ./services/monitoring/smartd.nix
   ./services/monitoring/statsd.nix
   ./services/monitoring/sysstat.nix
diff --git a/nixos/modules/services/monitoring/sensu/checks.nix b/nixos/modules/services/monitoring/sensu/checks.nix
new file mode 100644
index 000000000000..4343286177c4
--- /dev/null
+++ b/nixos/modules/services/monitoring/sensu/checks.nix
@@ -0,0 +1,76 @@
+{ lib }:
+
+{
+  options = with lib; with types; {
+    type = mkOption {
+      type = enum [ "standard" "metric" ];
+      default = "standard";
+      description = "Type of check.";
+    };
+
+    standalone = mkOption {
+      type = bool;
+      default = false;
+      description = "Scheduled by the client instead of the server.";
+    };
+
+    command = mkOption {
+      type = str;
+      description = "Command to run.";
+    };
+
+    subscribers = mkOption {
+      type = listOf str;
+      default = [];
+      description = "Subscribers";
+    };
+
+    handlers = mkOption {
+      default = [];
+      description = "Handlers.";
+      type = listOf str;
+    };
+
+    interval = mkOption {
+      type = int;
+      default = 60;
+      description = "Check interval.";
+    };
+
+    timeout = mkOption {
+      type = int;
+      default = 30;
+      description = "Check timeout.";
+    };
+
+    ttl = mkOption {
+      type = int;
+      default = 120;
+      description = "Check TTL.";
+    };
+
+    source = mkOption {
+      type = str;
+      default = "";
+      description = "Custom source for JIT checks.";
+    };
+
+    occurrences = mkOption {
+      type = int;
+      default = 1;
+      description = "The number of occurrences before triggering an alert.";
+    };
+
+    subdue = mkOption {
+      type = attrs;
+      default = {};
+      description = "Subdue check during certain windows.";
+    };
+
+    vars = mkOption {
+      type = attrs;
+      default = {};
+      description = "Custom variables sent with the check.";
+    };
+  };
+}
diff --git a/nixos/modules/services/monitoring/sensu/client.nix b/nixos/modules/services/monitoring/sensu/client.nix
new file mode 100644
index 000000000000..dc4c9864c09a
--- /dev/null
+++ b/nixos/modules/services/monitoring/sensu/client.nix
@@ -0,0 +1,49 @@
+{ lib }:
+
+{
+  options = with lib; with types; {
+    name = mkOption {
+      type = str;
+      default = "";
+      description = "Name of the client.";
+    };
+
+    address = mkOption {
+      type = str;
+      default = "";
+      description = "IP address";
+    };
+
+    subscriptions = mkOption {
+      type = listOf str;
+      default = [ ];
+      description = "Subscriptions";
+    };
+
+    socket = mkOption {
+      description = "The socket configuration.";
+      default = {};
+      type = submodule {
+        options = {
+          bind = mkOption {
+            type = str;
+            default = "127.0.0.1";
+            description = "The IP address on which the client listens.";
+          };
+
+          port = mkOption {
+            type = int;
+            default = 3030;
+            description = "The port on which the client listens.";
+          };
+        };
+      };
+    };
+
+    vars = mkOption {
+      type = attrs;
+      default = {};
+      description = "Custom attributes/variables.";
+    };
+  };
+}
diff --git a/nixos/modules/services/monitoring/sensu/dashboard.nix b/nixos/modules/services/monitoring/sensu/dashboard.nix
new file mode 100644
index 000000000000..dda38f2f8c43
--- /dev/null
+++ b/nixos/modules/services/monitoring/sensu/dashboard.nix
@@ -0,0 +1,112 @@
+{ config, lib, cfg }:
+
+{
+  options = with lib; with types; {
+    enable = mkOption {
+      type = bool;
+      default = (cfg.role == "server");
+      description = "Enable the dashboard";
+    };
+
+    host = mkOption {
+      type = str;
+      default = "127.0.0.1";
+      description = "The IP address on which Uchiwa will listen.";
+    };
+
+    port = mkOption {
+      type = int;
+      default = 3000;
+      description = "The port on which Uchiwa will listen.";
+    };
+
+    refresh = mkOption {
+      type = int;
+      default = 5;
+      description = "UI refresh interval.";
+    };
+
+    proxy = mkOption {
+      description = "Proxy traffic to/from the sensu dashboard.";
+      default = {};
+      type = submodule {
+        options = {
+          enable = mkOption {
+            type = bool;
+            default = false;
+            description = "Enable proxy.";
+          };
+
+          path = mkOption {
+            type = str;
+            default = "/";
+            description = "The path to the dashboard if behind a proxy.";
+          };
+
+          name = mkOption {
+            type = str;
+            default = config.networking.hostName;
+            description = "Hostname on which to repond.";
+          };
+
+          enableSSL = mkOption {
+            type = bool;
+            default = false;
+            description = "Force SSL.";
+          };
+        };
+      };
+    };
+
+    users = mkOption {
+      description = "Users";
+      default = {};
+      type = listOf(submodule {
+        options = {
+          username = mkOption {
+            description = "User name.";
+            type = str;
+          };
+
+          password = mkOption {
+            description = "Password.";
+            type = str;
+          };
+
+          accessToken = mkOption {
+            default = "";
+            description = "Access token.";
+            type = str;
+          };
+
+          readonly = mkOption {
+            default = false;
+            description = "Read only.";
+            type = bool;
+          };
+        };
+      });
+    };
+
+    usersOptions = mkOption {
+      description = "Options relevant to all users";
+      default = {};
+      type = submodule {
+        options = {
+
+          defaultTheme = mkOption {
+            type = enum [ "uchiwa-default" "uchiwa-dark" ];
+            default = "uchiwa-dark";
+            description = "The theme to use.";
+          };
+
+          logoUrl = mkOption {
+            type = str;
+            default = "";
+            description = "The logo to use.";
+          };
+        };
+      };
+    };
+  };
+}
diff --git a/nixos/modules/services/monitoring/sensu/default.nix b/nixos/modules/services/monitoring/sensu/default.nix
new file mode 100644
index 000000000000..463420b4c185
--- /dev/null
+++ b/nixos/modules/services/monitoring/sensu/default.nix
@@ -0,0 +1,710 @@
+{ config, pkgs, lib, ... }:
+
+let
+  cfg = config.services.sensu;
+  pgm = cfg.programs;
+
+  baseDir = "/etc/sensu";
+
+  transportIsRabbitMQ = (cfg.transport.name == "rabbitmq");
+  roleIsServer = (cfg.role == "server");
+
+  # Setting the LOG_LEVEL env var doesn't work, so we force the logLevel via -L
+  bin = binary: lib.concatStringsSep " " [
+    "${cfg.package}/bin/sensu-${binary}"
+    "-c ${baseDir}/config.json"
+    "-d ${baseDir}/conf.d"
+    "-e ${baseDir}/extensions"
+    "-L ${cfg.logLevel}"
+  ];
+
+  # Create a dedicated environment to allow for very long paths as systemd has a
+  # 2048 character limit
+  clientEnv = pkgs.buildEnv {
+    name = "sensu-env";
+    pathsToLink = [ "/bin" ];
+    paths = (with pkgs; [ gawk ]
+      ++ lib.optionals pgm.common  [ check-uptime monitoring-plugins ]
+      ++ lib.optionals pgm.esx     [ check-esxi-hardware ]
+      ++ lib.optionals pgm.http    [ curl ]
+      ++ lib.optionals pgm.ipmi    [ ipmitool which ]
+      ++ lib.optionals pgm.network [ check-nwc-health mtr ]
+      ++ lib.optionals pgm.openvpn [ sensu-check-openvpn ]
+      ++ lib.optionals pgm.snmp    [ net_snmp ]
+      ++ lib.optionals pgm.ups     [ check-ups-health ]
+      ++ cfg.dependencies
+  );};
+
+  sensuService = desc: bin:
+  let
+    pgm = lib.toLower desc;
+    isClient = lib.elem pgm [ "client" ];
+    isDash   = lib.elem pgm [ "dashboard" ];
+    isServer = lib.elem pgm [ "api" "server" ];
+  in {
+    description = "Sensu ${desc}";
+    wantedBy    = [ "sensu.target" ];
+    after       = []
+      ++ lib.optionals isServer [ "redis.service" "rabbmitmq.service" ];
+    # 1. Sensu is very shell-happy. I don't know if it actually requires bash
+    # per se, but it definitely needs a shell.
+    # 2. We need /run/wrappers early so the wrapped binary is found first
+    path = [ "/run/wrappers" pkgs.bash cfg.package ]
+      ++ lib.optional isClient clientEnv;
+
+    # Needed for bundler
+    environment.HOME = "/run/sensu";
+
+    restartTriggers = [ ]
+      ++ lib.optionals isClient [ sensuCfg clientCfg ]
+      ++ lib.optionals isDash   [ dashCfg ]
+      ++ lib.optionals isServer [ sensuCfg checkCfg filterCfg handlerCfg ];
+    serviceConfig = {
+      ExecStart        = bin;
+      # If you backport this to 17.03, DynamicUser WILL cause certain checks to
+      # fail as they expect to be able to resolve uid -> user name and the
+      # required NSS module isn't loaded (it is in master).
+      DynamicUser      = true;
+      Slice            = "sensu.slice";
+      Restart          = "on-failure";
+      # Upstream recommends 1m which seems VERY long
+      RestartSec       = "10s";
+      ProtectSystem    = "full";
+      # ProtectControlGroups = true;
+      # ProtectKernelTunables = true;
+      # ProtectKernelModules = true;
+      # SystemCallArchitectures = "native";
+
+      # Sensu expects a common file in $HOME which must be shared with the other
+      # sensu units this can be enabled when our systemd module gets support for
+      # JoinsNamespaceOf.
+      PrivateTmp       = true;
+      TimeoutStopSec   = "5s";
+      RuntimeDirectory = lib.mkIf isClient "sensu";
+      # NoNewPrivileges = true;
+    };
+  };
+
+  # This function serves two purposes:
+  #
+  # 1) We do a lot of attrs -> json but nix will add a "_module" key when
+  #    dumping a submodule which is at best noise and in the worst case causes
+  #    an unexpected setting to be set
+  #
+  # 2) We do not want to set defaults for everything (as defaults change), so if
+  #    a value is an empty string|list|set, we simply remove the key from the
+  #    generated JSON to allow sensu to apply its own defaults
+
+  cleanAttrSet = set_or_list:
+    if builtins.isList set_or_list
+      then (map (s: cleanAttrSet s) set_or_list)
+      else lib.filterAttrsRecursive (k: v:
+            !(k == "_module" || v == "" || v == [] || v == {})) set_or_list;
+
+  checkCfg = pkgs.writeText "checks.json" (builtins.toJSON (cleanAttrSet {
+    inherit (cfg) checks;
+  }));
+
+  filterCfg = pkgs.writeText "filters.json" (builtins.toJSON (cleanAttrSet {
+    inherit (cfg) filters;
+  }));
+
+  handlerCfg = pkgs.writeText "handlers.json" (builtins.toJSON (cleanAttrSet {
+    inherit (cfg) handlers;
+  } // cfg.plugins));
+
+  mutatorCfg = pkgs.writeText "mutators.json" (builtins.toJSON (cleanAttrSet {
+    inherit (cfg) mutators;
+  }));
+
+  sensuCfg = let
+    rabbitmq = cleanAttrSet cfg.rabbitmq;
+  in pkgs.writeText "config.json" (builtins.toJSON ({
+    inherit rabbitmq;
+  } // (cleanAttrSet (if roleIsServer
+    then { inherit (cfg) api extensions influxdb mutators redis transport; } // cfg.extraServerConfig
+    else { inherit (cfg)     extensions                         transport; } // cfg.extraClientConfig))));
+
+  clientCfg = pkgs.writeText "client.json" (builtins.toJSON (cleanAttrSet {
+    inherit (cfg) client;
+  }));
+
+  dashCfg = pkgs.writeText "uchiwa.json" (builtins.toJSON (cleanAttrSet {
+    sensu = cleanAttrSet cfg.sites;
+    uchiwa = cfg.dashboard // {
+      loglevel = cfg.logLevel;
+    };
+  }));
+
+  # Currently not used
+  makePlugin = name: config: base:
+    let
+      fileName = "plugin-${name}.json";
+    in {
+      source = pkgs.writeText fileName (builtins.toJSON { "${name}" = config; });
+      target = "${base}/${fileName}";
+    };
+
+in {
+
+  options = {
+    services.sensu = with lib; with types; {
+      enable = mkOption {
+        type = bool;
+        default = false;
+        description = ''
+          Enable the Sensu network monitoring daemon.
+        '';
+      };
+
+      # Add support for dashboard rabbitmq redis etc
+      role = mkOption {
+        # type = listOf enum [ "server" "client" "dashboard" "influxdb" "rabbmitmq" "redis" ];
+        type = enum [ "server" "client" ];
+        # default = [ "server" ];
+        default = "server";
+        description = "Operate as client only or server and client.";
+      };
+
+      transport = mkOption {
+        default = {};
+        description = "The transport.";
+        type = submodule {
+          options = {
+            name = mkOption {
+              type = enum [ "redis" "rabbitmq" ];
+              default = "redis";
+              description = "The transport to use.";
+            };
+
+            reconnect_on_error = mkOption {
+              type = bool;
+              default = true;
+              description = "Automatically reconnect on error.";
+            };
+          };
+        };
+      };
+
+      openDefaultPorts = mkOption {
+        type = bool;
+        default = false;
+        description = "Automatically open the firewall ports.";
+      };
+
+      defaultClientSubscriptions = mkOption {
+        type = listOf str;
+        default = [ "sensu-client" ];
+        description = "Default subscriptions for sensu clients.";
+      };
+
+      defaultServerSubscriptions = mkOption {
+        type = listOf str;
+        default = [ "sensu-server" ];
+        description = "Default subscriptions for sensu servers.";
+      };
+
+      defaultSubscriptions = {
+        enable = mkEnableOption "Default checks of the sensu environment.";
+
+        interval = mkOption {
+          description = "How frequently to run interval checks.";
+          default = 60;
+          type = int;
+        };
+
+        occurrences = mkOption {
+          description = "How many occurrences before we trigger an alert.";
+          default = 2;
+          type = int;
+        };
+      };
+
+      package = mkOption {
+        type = package;
+        default = pkgs.sensu;
+        description = "The package to use.";
+      };
+
+      dependencies = mkOption {
+        type = listOf package;
+        default = [];
+        description = "Additional packages to inject into the path.";
+      };
+
+      logLevel = mkOption {
+        type = enum [ "debug" "info" "warn" "error" "fatal" ];
+        default = "info";
+        description = ''The level of logging. The default info is VERY verbose
+          and you probably want to change this to 'warn' when things are working
+        '';
+      };
+
+      extraClientConfig = mkOption {
+        type = attrs;
+        default = {};
+        description = "Additional configuration data that will be added to the client config.";
+      };
+
+      extraServerConfig = mkOption {
+        type = attrs;
+        default = {};
+        description = "Additional configuration data that will be added to the server config.";
+      };
+
+      extensions = mkOption {
+        type = attrs;
+        default = {};
+        description = "Extensions to load.";
+      };
+
+      redis = mkOption {
+        description = "Redis configuration.";
+        default = {};
+        type = (submodule (import ./host_port_pair.nix {
+          inherit lib;
+          name = "redis";
+          defaultHost = "127.0.0.1";
+          defaultPort = 6379;
+        }));
+      };
+
+      influxdb = mkOption {
+        description = "InfluxDB configuration.";
+        default = {};
+        type = (submodule (import ./host_port_pair.nix {
+            inherit lib;
+            name = "influxdb";
+            defaultHost = "localhost";
+            defaultPort = 8086;
+            options = {
+              database = mkOption {
+                default = "sensu";
+                description = "InfluxDB database";
+                type = str;
+              };
+
+              user = mkOption {
+                default = null;
+                description = "InfluxDB user";
+                type = nullOr str;
+              };
+
+              password = mkOption {
+                default = null;
+                description = "InfluxDB password";
+                type = nullOr str;
+              };
+
+              templates = mkOption {
+                default = {};
+                description = "Templates";
+                type = attrs;
+              };
+            };
+        }));
+      };
+
+      rabbitmq = mkOption {
+        description = "RabbitMQ configuration.";
+        default = [];
+        type = listOf (submodule (import ./host_port_pair.nix {
+            inherit lib;
+            name = "rabbitmq";
+            defaultHost = "127.0.0.1";
+            defaultPort = config.services.rabbitmq.port;
+            options = {
+              vhost = mkOption {
+                default = "/sensu";
+                description = "RabbitMQ vhost";
+                type = str;
+              };
+
+              user = mkOption {
+                default = "sensu";
+                description = "RabbitMQ user";
+                type = str;
+              };
+
+              password = mkOption {
+                description = "RabbitMQ password";
+                type = str;
+              };
+
+              heartbeat = mkOption {
+                default = 30;
+                description = "RabbitMQ heartbeat";
+                type = int;
+              };
+
+              prefetch = mkOption {
+                default = 50;
+                description = "RabbitMQ prefetch";
+                type = int;
+              };
+
+              ssl = mkOption {
+                default = {};
+                description = "RabbitMQ SSL options.";
+                type = submodule {
+                  options = {
+                    cert_chain_file = mkOption {
+                      default = "";
+                      description = "Path to the cert chain file.";
+                      type = str;
+                    };
+
+                    private_key_file = mkOption {
+                      default = "";
+                      description = "Path to the private key file.";
+                      type = str;
+                    };
+                  };
+                };
+              };
+            };
+        }));
+      };
+
+      configureInfluxDb = mkOption {
+        default = false;
+        description = "Whether the database should be configured for Sensu on InfluxDB.";
+        type = bool;
+      };
+
+      configureRabbitMq = mkOption {
+        default = false;
+        description = "Whether the vhost/user/permissions should be configured for Sensu on RabbitMQ.";
+        type = bool;
+      };
+
+      api = mkOption {
+        description = "API server configuration.";
+        default = {};
+        type = (submodule (import ./host_port_pair.nix {
+          inherit lib;
+          name = "api";
+          defaultHost = "127.0.0.1";
+          defaultPort = 4567;
+          options = {
+            bind = mkOption {
+              type = str;
+              default = "0.0.0.0";
+              description = "The address that the API will bind to (listen on).";
+            };
+          };
+        }));
+      };
+
+      programs = let
+        programOption = name: default: mkOption {
+          type = bool;
+          description = "Enable support for ${name}.";
+          inherit default;
+        }; in mkOption {
+        description = "Programs to enable for checks";
+        default = {};
+        type = submodule {
+          options = {
+            # some of the built-in checks require the common package
+            common  = programOption "common"  true;
+            esx     = programOption "esx"     false;
+            http    = programOption "http"    false;
+            ipmi    = programOption "ipmi"    false;
+            network = programOption "network" false;
+            openvpn = programOption "openvpn" false;
+            snmp    = programOption "snmp"    false;
+            ups     = programOption "ups"     false;
+          };
+        };
+      };
+
+      checks = mkOption {
+        type = with types; attrsOf (submodule (import ./checks.nix { inherit lib; }));
+        default = {};
+        description = "The checks configured.";
+      };
+
+      client = mkOption {
+        description = "The client configuration.";
+        default = {};
+        type = submodule (import ./client.nix { inherit lib; });
+      };
+
+      dashboard = mkOption {
+        description = "The Sensu dashboard.";
+        default = {};
+        type = submodule (import ./dashboard.nix { inherit cfg config lib; });
+      };
+
+      filters = mkOption {
+        type = attrs;
+        default = {};
+        description = "The filters available to Sensu.";
+      };
+
+      handlers = mkOption {
+        type = with types; attrsOf (submodule (import ./handlers.nix { inherit lib; }));
+        default = {};
+        description = "The handlers available to Sensu.";
+      };
+
+      mutators = mkOption {
+        type = with types; attrsOf (submodule (import ./mutators.nix { inherit lib; }));
+        default = {};
+        description = "The mutators available to Sensu.";
+      };
+
+      sites = mkOption {
+        type = listOf (submodule (import ./sites.nix { inherit lib; }));
+        description = "The sites configured.";
+        default = [];
+      };
+
+      plugins = mkOption {
+        type = attrs;
+        description = "Plugin configuration.";
+        default = {};
+      };
+    };
+  };
+
+  config = lib.mkIf cfg.enable {
+
+    # Needed for being able to process UDP traffic
+    boot.kernel.sysctl = lib.mkDefault {
+      "net.core.rmem_max"     = 26214400;
+      "net.core.rmem_default" = 26214400;
+    };
+
+    environment = let dir = "${lib.removePrefix "/etc/" baseDir}/conf.d"; in {
+      etc = {
+        checks = lib.mkIf roleIsServer {
+          source = checkCfg;
+          target = "${dir}/checks.json";
+        };
+        filters = lib.mkIf roleIsServer {
+          source = filterCfg;
+          target = "${dir}/filters.json";
+        };
+        handlers = lib.mkIf roleIsServer {
+          source = handlerCfg;
+          target = "${dir}/handlers.json";
+        };
+        # influxdb_line_protocol = {
+          # source = "${cfg.package}/bin/mutator-influxdb-line-protocol.rb";
+          # target = "sensu/extensions/mutator-influxdb-line-protocol.rb";
+        # };
+        uchiwa = lib.mkIf roleIsServer {
+          source = dashCfg;
+          target = "sensu/uchiwa.json";
+        };
+        client = {
+          source = clientCfg;
+          target = "${dir}/client.json";
+        };
+        config = {
+          source = sensuCfg;
+          target = "sensu/config.json";
+        };
+      };
+
+      systemPackages = with pkgs; [
+        jq
+        nmap
+        tree
+      ];
+    };
+
+    networking.firewall.allowedTCPPorts = lib.mkIf cfg.openDefaultPorts ([]
+      ++ lib.optional (cfg.client.socket != "127.0.0.1") cfg.client.socket.port
+      ++ lib.optional roleIsServer                       cfg.api.port
+      ++ lib.optional (cfg.dashboard.enable)             cfg.dashboard.port
+    );
+
+    services = let pcfg = cfg.dashboard.proxy; in {
+      nginx = lib.mkIf pcfg.enable {
+        enable = true;
+        virtualHosts = {
+          "${pcfg.name}" = rec {
+            addSSL     = pcfg.enableSSL;
+            enableACME = addSSL;
+            extraConfig = let
+              inherit (pcfg) enable path;
+            in ''
+              location ${path} {
+                proxy_pass http://localhost:${toString cfg.dashboard.port};
+                proxy_http_version 1.1;
+                proxy_set_header Upgrade $http_upgrade;
+                proxy_set_header Connection "upgrade";
+                proxy_set_header Host $host;
+
+                rewrite ${path}(.*) /$1 break;
+              }
+            '';
+          };
+        };
+      };
+
+      rabbitmq = lib.mkIf (roleIsServer && transportIsRabbitMQ) {
+        enable = true;
+      };
+
+      redis = lib.mkIf roleIsServer {
+        enable = true;
+        bind = "127.0.0.1";
+      };
+
+      sensu = {
+        checks = let disk = { warn = 20; crit = 10; }; in {
+          sensu-disk-root = {
+            command = lib.concatStringsSep " " [
+               "check_disk"
+               "--warning=${toString disk.warn}"
+               "--critical=${toString disk.crit}"
+               "--path=/"
+            ];
+            subscribers = cfg.defaultServerSubscriptions ++ cfg.defaultClientSubscriptions;
+            inherit (cfg.defaultSubscriptions) interval occurrences;
+          };
+
+          sensu-disk-var = {
+            command = lib.concatStringsSep " " [
+               "check_disk"
+               "--warning=${toString disk.warn}"
+               "--critical=${toString disk.crit}"
+               "--path=/var"
+            ];
+            subscribers = cfg.defaultServerSubscriptions ++ cfg.defaultClientSubscriptions;
+            inherit (cfg.defaultSubscriptions) interval occurrences;
+          };
+
+          sensu-load = {
+            command = lib.concatStringsSep " " [
+              "check_load"
+              "--warning=2.75,2.50,2.00"
+              "--critical=3.50,3.25,3.00"
+              "--percpu"
+            ];
+            subscribers = cfg.defaultServerSubscriptions ++ cfg.defaultClientSubscriptions;
+            inherit (cfg.defaultSubscriptions) interval occurrences;
+          };
+
+          sensu-swap = {
+            command = lib.concatStringsSep " " [
+              "check_swap"
+              "--warning=50%"
+              "--critical=20%"
+              "--no-swap=ok"
+            ];
+            subscribers = cfg.defaultServerSubscriptions ++ cfg.defaultClientSubscriptions;
+            inherit (cfg.defaultSubscriptions) interval occurrences;
+          };
+
+          sensu-time = {
+            command = lib.concatStringsSep " " [
+              "check_ntp_time"
+              "-H :::vars.ntp.host|0.nixos.pool.ntp.org:::"
+            ];
+            subscribers = cfg.defaultServerSubscriptions;
+            inherit (cfg.defaultSubscriptions) interval occurrences;
+          };
+
+          sensu-uptime = {
+            command = lib.concatStringsSep " " [
+              "check_uptime"
+              "--warning 3:"
+            ];
+            subscribers = cfg.defaultServerSubscriptions ++ cfg.defaultClientSubscriptions;
+            inherit (cfg.defaultSubscriptions) interval occurrences;
+          };
+
+          sensu-influx-ping = {
+            command = lib.concatStringsSep " " [
+              "check-influxdb.rb"
+              "--host ${cfg.influxdb.host}"
+              "--port ${toString cfg.influxdb.port}"
+            ];
+            subscribers = cfg.defaultServerSubscriptions;
+            inherit (cfg.defaultSubscriptions) interval occurrences;
+          };
+
+          sensu-redis-mem = {
+            command = lib.concatStringsSep " " [
+              "check-redis-memory-percentage.rb"
+              "--host ${cfg.redis.host}"
+              "--port ${toString cfg.redis.port}"
+              "--critmem 90"
+              "--warnmem 70"
+            ];
+            subscribers = cfg.defaultServerSubscriptions;
+            inherit (cfg.defaultSubscriptions) interval occurrences;
+          };
+
+          sensu-error-log = {
+            command = lib.concatStringsSep " " [
+              "check-journal.rb"
+              "--journalctl_args='-p err --quiet' -q ''"
+            ];
+            subscribers = cfg.defaultServerSubscriptions ++ cfg.defaultClientSubscriptions;
+            inherit (cfg.defaultSubscriptions) interval occurrences;
+          };
+        };
+
+        client.subscriptions = lib.mkIf cfg.defaultSubscriptions.enable (
+           if roleIsServer then cfg.defaultServerSubscriptions
+                           else cfg.defaultClientSubscriptions
+        );
+
+        extensions = {
+          influxdb =  {
+            gem = "sensu-extensions-influxdb";
+          };
+        };
+      };
+    };
+
+    systemd = let
+      runRabbitMq = (roleIsServer && transportIsRabbitMQ && cfg.configureRabbitMq);
+    in {
+      services = {
+        sensu-api       = lib.mkIf roleIsServer         (sensuService "API"       (bin "api"));
+        sensu-client    =                               (sensuService "Client"    (bin "client"));
+        sensu-server    = lib.mkIf roleIsServer         (sensuService "Server"    (bin "server"));
+        sensu-dashboard = lib.mkIf cfg.dashboard.enable (sensuService "Dashboard"
+          "${pkgs.uchiwa}/bin/uchiwa -c ${baseDir}/uchiwa.json"
+        );
+
+        rabbitmq = lib.mkIf runRabbitMq {
+          wants = [ "rabbitmq-setup.service" ];
+        };
+
+        rabbitmq-setup = lib.mkIf runRabbitMq (
+        let
+          rmq = builtins.head config.services.sensu.rabbitmq;
+          service = [ "rabbitmq.service" ];
+        in lib.mkIf transportIsRabbitMQ {
+          description = "Configure RabbitMQ queue and user for Sensu";
+          wants = service;
+          after = service;
+          script = ''
+            export HOME=${config.services.rabbitmq.dataDir}
+            export PATH=${lib.makeBinPath (with pkgs; [ coreutils gnused rabbitmq_server ])}:$PATH
+
+            rabbitmqctl add_vhost ${rmq.vhost}
+            rabbitmqctl add_user  ${rmq.user} '${rmq.password}'
+            rabbitmqctl set_permissions -p ${rmq.vhost} ${rmq.user} ".*" ".*" ".*"
+
+            # get rid of guest
+            rabbitmqctl delete_user guest
+          '';
+        });
+      };
+
+      targets.sensu = {
+        description = "Sensu Monitoring";
+        wantedBy    = [ "multi-user.target" ];
+      };
+    };
+  };
+}
diff --git a/nixos/modules/services/monitoring/sensu/handlers.nix b/nixos/modules/services/monitoring/sensu/handlers.nix
new file mode 100644
index 000000000000..befe50fa8340
--- /dev/null
+++ b/nixos/modules/services/monitoring/sensu/handlers.nix
@@ -0,0 +1,70 @@
+{ lib }:
+
+{
+  options = with lib; with types; {
+    type = mkOption {
+      description = "Type of handler.";
+      type = enum [ "pipe" "tcp" "udp" "transport" "set" ];
+    };
+
+    filters = mkOption {
+      default = [];
+      description = "List of filters.";
+      type = listOf str;
+    };
+
+    severities = mkOption rec {
+      default = [ "critical" "warning" "unknown" ];
+      description = "Severities to handle.";
+      type = listOf (enum (default ++ [ "ok" ]));
+    };
+
+    subscribers = mkOption {
+      default = [];
+      description = "Subscribers";
+      type = listOf str;
+    };
+
+    timeout = mkOption {
+      default = 30;
+      description = "Timeout.";
+      type = int;
+    };
+
+    command = mkOption {
+      default = "";
+      description = "Command for type pipe.";
+      type = str;
+    };
+
+    socket = mkOption {
+      default = {};
+      description = "Socket for type tcp or udp.";
+      type = attrs;
+    };
+
+    pipe = mkOption {
+      default = {};
+      description = "Pipe for type pipe.";
+      type = attrs;
+    };
+
+    mutator = mkOption {
+      default = "";
+      description = "Mutator.";
+      type = str;
+    };
+
+    handlers = mkOption {
+      default = [];
+      description = "Handlers for type set.";
+      type = listOf str;
+    };
+
+    subdue = mkOption {
+      type = attrs;
+      default = {};
+      description = "Subdue handler during certain windows.";
+    };
+  };
+}
diff --git a/nixos/modules/services/monitoring/sensu/host_port_pair.nix b/nixos/modules/services/monitoring/sensu/host_port_pair.nix
new file mode 100644
index 000000000000..283a8f59acfd
--- /dev/null
+++ b/nixos/modules/services/monitoring/sensu/host_port_pair.nix
@@ -0,0 +1,17 @@
+{ lib, name, defaultHost ? null, defaultPort ? null, options ? {} }:
+
+{
+  options = with lib; with types; {
+    host = mkOption {
+      type = str;
+      default = defaultHost;
+      description = "The hostname of ${name}";
+    };
+
+    port = mkOption {
+      type = int;
+      default = defaultPort;
+      description = "The port of ${name}";
+    };
+  } // options;
+}
diff --git a/nixos/modules/services/monitoring/sensu/mutators.nix b/nixos/modules/services/monitoring/sensu/mutators.nix
new file mode 100644
index 000000000000..9325ec480e99
--- /dev/null
+++ b/nixos/modules/services/monitoring/sensu/mutators.nix
@@ -0,0 +1,17 @@
+{ lib }:
+
+{
+  options = with lib; with types; {
+    command = mkOption {
+      default = "";
+      description = "Command for mutator.";
+      type = str;
+    };
+
+    timeout = mkOption {
+      default = 30;
+      description = "Timeout.";
+      type = int;
+    };
+  };
+}
diff --git a/nixos/modules/services/monitoring/sensu/plugins.nix b/nixos/modules/services/monitoring/sensu/plugins.nix
new file mode 100644
index 000000000000..95d70f88391b
--- /dev/null
+++ b/nixos/modules/services/monitoring/sensu/plugins.nix
@@ -0,0 +1,83 @@
+{ lib }:
+
+{
+  options = with lib; with types; {
+
+    mailer = mkOption {
+      description = "sensu-plugins-mailer";
+      default = {};
+      type = submodule {
+        options = {
+          mail_from = mkOption {
+            type = str;
+            description = "Sender";
+          };
+
+          mail_to = mkOption {
+            type = str;
+            description = "Recipient";
+          };
+        };
+      };
+    };
+  };
+}
+
+
+
+
+
+#     type = mkOption {
+#       type = enum [ "pipe" "tcp" "udp" "transport" "set" ];
+#       description = "Type of handler.";
+#     };
+
+#     filters = mkOption {
+#       type = listOf str;
+#       default = [];
+#       description = "List of filters.";
+#     };
+
+#     severities = mkOption {
+#       type = listOf (enum [ "warning" "critical" "unknown" ]);
+#       default = [ "unknown" ];
+#       description = "Severities to handle.";
+#     };
+
+#     subscribers = mkOption {
+#       type = listOf str;
+#       default = [];
+#       description = "Subscribers";
+#     };
+
+#     timeout = mkOption {
+#       type = int;
+#       default = 30;
+#       description = "Timeout.";
+#     };
+
+#     command = mkOption {
+#       type = str;
+#       default = "";
+#       description = "Command for type pipe.";
+#     };
+
+#     socket = mkOption {
+#       type = attrs;
+#       default = {};
+#       description = "Socket for type tcp or udp.";
+#     };
+
+#     pipe = mkOption {
+#       type = attrs;
+#       default = {};
+#       description = "Pipe for type pipe.";
+#     };
+
+#     handlers = mkOption {
+#       type = listOf str;
+#       default = [];
+#       description = "Handlers for type set.";
+#     };
+#   };
+# }
diff --git a/nixos/modules/services/monitoring/sensu/sites.nix b/nixos/modules/services/monitoring/sensu/sites.nix
new file mode 100644
index 000000000000..f983305d825c
--- /dev/null
+++ b/nixos/modules/services/monitoring/sensu/sites.nix
@@ -0,0 +1,59 @@
+{ lib }:
+
+{
+  options = with lib; {
+    name = mkOption {
+      type = types.str;
+      default = "Site 1";
+      description = "Name of the site.";
+    };
+
+    host = mkOption {
+      type = types.str;
+      default = "localhost";
+      description = "Host name";
+    };
+
+    port = mkOption {
+      type = types.int;
+      default = 4567;
+      description = "Port";
+    };
+
+    ssl = mkOption {
+      type = types.bool;
+      default = true;
+      description = "Enable SSL";
+    };
+
+    insecure = mkOption {
+      type = types.bool;
+      default = true;
+      description = "Insecure";
+    };
+
+    user = mkOption {
+      type = types.str;
+      default = "";
+      description = "User name for authentication";
+    };
+
+    pass = mkOption {
+      type = types.str;
+      default = "";
+      description = "Password for authentication";
+    };
+
+    path = mkOption {
+      type = types.str;
+      default = "";
+      description = "Path?";
+    };
+
+    timeout = mkOption {
+      type = types.int;
+      default = 5;
+      description = "Timeout";
+    };
+  };
+}