{ config, lib, pkgs, ... }: with lib; let cfg = config.services.logstash; ops = lib.optionalString; verbosityFlag = "--log.level " + cfg.logLevel; logstashConf = pkgs.writeText "logstash.conf" '' input { ${cfg.inputConfig} } filter { ${cfg.filterConfig} } output { ${cfg.outputConfig} } ''; logstashSettingsYml = pkgs.writeText "logstash.yml" cfg.extraSettings; logstashJvmOptionsFile = pkgs.writeText "jvm.options" cfg.extraJvmOptions; logstashSettingsDir = pkgs.runCommand "logstash-settings" { inherit logstashJvmOptionsFile; inherit logstashSettingsYml; preferLocalBuild = true; } '' mkdir -p $out ln -s $logstashSettingsYml $out/logstash.yml ln -s $logstashJvmOptionsFile $out/jvm.options ''; in { imports = [ (mkRenamedOptionModule [ "services" "logstash" "address" ] [ "services" "logstash" "listenAddress" ]) (mkRemovedOptionModule [ "services" "logstash" "enableWeb" ] "The web interface was removed from logstash") ]; ###### interface options = { services.logstash = { enable = mkOption { type = types.bool; default = false; description = lib.mdDoc "Enable logstash."; }; package = mkPackageOption pkgs "logstash" { }; plugins = mkOption { type = types.listOf types.path; default = [ ]; example = literalExpression "[ pkgs.logstash-contrib ]"; description = lib.mdDoc "The paths to find other logstash plugins in."; }; dataDir = mkOption { type = types.str; default = "/var/lib/logstash"; description = lib.mdDoc '' A path to directory writable by logstash that it uses to store data. Plugins will also have access to this path. ''; }; logLevel = mkOption { type = types.enum [ "debug" "info" "warn" "error" "fatal" ]; default = "warn"; description = lib.mdDoc "Logging verbosity level."; }; filterWorkers = mkOption { type = types.int; default = 1; description = lib.mdDoc "The quantity of filter workers to run."; }; listenAddress = mkOption { type = types.str; default = "127.0.0.1"; description = lib.mdDoc "Address on which to start webserver."; }; port = mkOption { type = types.str; default = "9292"; description = lib.mdDoc "Port on which to start webserver."; }; inputConfig = mkOption { type = types.lines; default = "generator { }"; description = lib.mdDoc "Logstash input configuration."; example = literalExpression '' ''' # Read from journal pipe { command => "''${config.systemd.package}/bin/journalctl -f -o json" type => "syslog" codec => json {} } ''' ''; }; filterConfig = mkOption { type = types.lines; default = ""; description = lib.mdDoc "logstash filter configuration."; example = '' if [type] == "syslog" { # Keep only relevant systemd fields # https://www.freedesktop.org/software/systemd/man/systemd.journal-fields.html prune { whitelist_names => [ "type", "@timestamp", "@version", "MESSAGE", "PRIORITY", "SYSLOG_FACILITY" ] } } ''; }; outputConfig = mkOption { type = types.lines; default = "stdout { codec => rubydebug }"; description = lib.mdDoc "Logstash output configuration."; example = '' redis { host => ["localhost"] data_type => "list" key => "logstash" codec => json } elasticsearch { } ''; }; extraSettings = mkOption { type = types.lines; default = ""; description = lib.mdDoc "Extra Logstash settings in YAML format."; example = '' pipeline: batch: size: 125 delay: 5 ''; }; extraJvmOptions = mkOption { type = types.lines; default = ""; description = lib.mdDoc "Extra JVM options, one per line (jvm.options format)."; example = '' -Xms2g -Xmx2g ''; }; }; }; ###### implementation config = mkIf cfg.enable { systemd.services.logstash = { description = "Logstash Daemon"; wantedBy = [ "multi-user.target" ]; path = [ pkgs.bash ]; serviceConfig = { ExecStartPre = ''${pkgs.coreutils}/bin/mkdir -p "${cfg.dataDir}" ; ${pkgs.coreutils}/bin/chmod 700 "${cfg.dataDir}"''; ExecStart = concatStringsSep " " (filter (s: stringLength s != 0) [ "${cfg.package}/bin/logstash" "-w ${toString cfg.filterWorkers}" (concatMapStringsSep " " (x: "--path.plugins ${x}") cfg.plugins) "${verbosityFlag}" "-f ${logstashConf}" "--path.settings ${logstashSettingsDir}" "--path.data ${cfg.dataDir}" ]); }; }; }; }