nixos/alerta: create new module + add kapacitor integration

nixos/modules/misc/ids.nix

@@ -334,6 +334,7 @@
       slurm = 307;
       kapacitor = 308;
       solr = 309;
+      alerta = 310;
 
       # When adding a uid, make sure it doesn't match an existing gid. And don't use uids above 399!
 
@@ -628,6 +629,7 @@
       slurm = 307;
       kapacitor = 308;
       solr = 309;
+      alerta = 310;
 
       # When adding a gid, make sure it doesn't match an existing
       # uid. Users and groups with the same name should have equal

nixos/modules/module-list.nix

@@ -419,6 +419,7 @@
   ./services/misc/weechat.nix
   ./services/misc/xmr-stak.nix
   ./services/misc/zookeeper.nix
+  ./services/monitoring/alerta.nix
   ./services/monitoring/apcupsd.nix
   ./services/monitoring/arbtt.nix
   ./services/monitoring/bosun.nix

nixos/modules/services/monitoring/alerta.nix

@@ -0,0 +1,116 @@
+{ options, config, lib, pkgs, ... }:
+
+with lib;
+
+let
+  cfg = config.services.alerta;
+
+  alertaConf = pkgs.writeTextFile {
+    name = "alertad.conf";
+    text = ''
+      DATABASE_URL = '${cfg.databaseUrl}'
+      DATABASE_NAME = '${cfg.databaseName}'
+      LOG_FILE = '${cfg.logDir}/alertad.log'
+      LOG_FORMAT = '%(asctime)s - %(name)s - %(levelname)s - %(message)s'
+      CORS_ORIGINS = [ ${concatMapStringsSep ", " (s: "\"" + s + "\"") cfg.corsOrigins} ];
+      AUTH_REQUIRED = ${if cfg.authenticationRequired then "True" else "False"}
+      SIGNUP_ENABLED = ${if cfg.signupEnabled then "True" else "False"}
+      ${cfg.extraConfig}
+    '';
+  };
+in
+{
+  options.services.alerta = {
+    enable = mkEnableOption "alerta";
+
+    port = mkOption {
+      type = types.int;
+      default = 5000;
+      description = "Port of Alerta";
+    };
+
+    bind = mkOption {
+      type = types.str;
+      default = "0.0.0.0";
+      example = literalExample "0.0.0.0";
+      description = "Address to bind to. The default is to bind to all addresses";
+    };
+
+    logDir = mkOption {
+      type = types.path;
+      description = "Location where the logfiles are stored";
+      default = "/var/log/alerta";
+    };
+
+    databaseUrl = mkOption {
+      type = types.str;
+      description = "URL of the MongoDB or PostgreSQL database to connect to";
+      default = "mongodb://localhost";
+      example = "mongodb://localhost";
+    };
+
+    databaseName = mkOption {
+      type = types.str;
+      description = "Name of the database instance to connect to";
+      default = "monitoring";
+      example = "monitoring";
+    };
+
+    corsOrigins = mkOption {
+      type = types.listOf types.str;
+      description = "List of URLs that can access the API for Cross-Origin Resource Sharing (CORS)";
+      example = [ "http://localhost" "http://localhost:5000" ];
+      default = [ "http://localhost" "http://localhost:5000" ];
+    };
+
+    authenticationRequired = mkOption {
+      type = types.bool;
+      description = "Whether users must authenticate when using the web UI or command-line tool";
+      default = false;
+    };
+
+    signupEnabled = mkOption {
+      type = types.bool;
+      description = "Whether to prevent sign-up of new users via the web UI";
+      default = true;
+    };
+
+    extraConfig = mkOption {
+      description = "These lines go into alertad.conf verbatim.";
+      default = "";
+      type = types.lines;
+    };
+  };
+
+  config = mkIf cfg.enable {
+    systemd.services.alerta = {
+      description = "Alerta Monitoring System";
+      wantedBy = [ "multi-user.target" ];
+      after = [ "networking.target" ];
+      environment = {
+        ALERTA_SVR_CONF_FILE = alertaConf;
+      };
+      serviceConfig = {
+        ExecStart = "${pkgs.python36Packages.alerta-server}/bin/alertad run --port ${toString cfg.port} --host ${cfg.bind}";
+        User = "alerta";
+        Group = "alerta";
+        PermissionsStartOnly = true;
+      };
+      preStart = ''
+        mkdir -p ${cfg.logDir}
+        chown alerta:alerta ${cfg.logDir}
+      '';
+    };
+
+    environment.systemPackages = [ pkgs.python36Packages.alerta ];
+
+    users.users.alerta = {
+      uid = config.ids.uids.alerta;
+      description = "Alerta user";
+    };
+
+    users.groups.alerta = {
+      gid = config.ids.gids.alerta;
+    };
+  };
+}

nixos/modules/services/monitoring/kapacitor.nix

@@ -42,6 +42,15 @@ let
           password = "${cfg.defaultDatabase.password}"
       ''}
 
+      ${optionalString (cfg.alerta.enable) ''
+        [alerta]
+          enabled = true
+          url = "${cfg.alerta.url}"
+          token = "${cfg.alerta.token}"
+          environment = "${cfg.alerta.environment}"
+          origin = "${cfg.alerta.origin}"
+      ''}
+
       ${cfg.extraConfig}
     '';
   };
@@ -120,6 +129,35 @@ in
         type = types.string;
       };
     };
+
+    alerta = {
+      enable = mkEnableOption "kapacitor alerta integration";
+
+      url = mkOption {
+        description = "The URL to the Alerta REST API";
+        default = "http://localhost:5000";
+        example = "http://localhost:5000";
+        type = types.string;
+      };
+
+      token = mkOption {
+        description = "Default Alerta authentication token";
+        type = types.str;
+        default = "";
+      };
+
+      environment = mkOption {
+        description = "Default Alerta environment";
+        type = types.str;
+        default = "Production";
+      };
+
+      origin = mkOption {
+        description = "Default origin of alert";
+        type = types.str;
+        default = "kapacitor";
+      };
+    };
   };
 
   config = mkIf cfg.enable {