{ config, lib, pkgs, ... }: with lib; let cfg = config.services.logstash; pluginPath = lib.concatStringsSep ":" cfg.plugins; havePluginPath = lib.length cfg.plugins > 0; ops = lib.optionalString; verbosityFlag = "--log.level " + cfg.logLevel; pluginsPath = "--path.plugins ${pluginPath}"; logstashConf = pkgs.writeText "logstash.conf" '' input { ${cfg.inputConfig} } filter { ${cfg.filterConfig} } output { ${cfg.outputConfig} } ''; logstashSettingsYml = pkgs.writeText "logstash.yml" cfg.extraSettings; logstashSettingsDir = pkgs.runCommand "logstash-settings" {inherit logstashSettingsYml;} '' mkdir -p $out ln -s $logstashSettingsYml $out/logstash.yml ''; in { ###### interface options = { services.logstash = { enable = mkOption { type = types.bool; default = false; description = "Enable logstash."; }; package = mkOption { type = types.package; default = pkgs.logstash; defaultText = "pkgs.logstash"; example = literalExample "pkgs.logstash5"; description = "Logstash package to use."; }; plugins = mkOption { type = types.listOf types.path; default = [ ]; example = literalExample "[ pkgs.logstash-contrib ]"; description = "The paths to find other logstash plugins in."; }; dataDir = mkOption { type = types.str; default = "/var/lib/logstash"; description = '' A path to directory writable by logstash that it uses to store data. Plugins will also have access to this path. ''; }; logLevel = mkOption { type = types.enum [ "debug" "info" "warn" "error" "fatal" ]; default = "warn"; description = "Logging verbosity level."; }; filterWorkers = mkOption { type = types.int; default = 1; description = "The quantity of filter workers to run."; }; listenAddress = mkOption { type = types.str; default = "127.0.0.1"; description = "Address on which to start webserver."; }; port = mkOption { type = types.str; default = "9292"; description = "Port on which to start webserver."; }; inputConfig = mkOption { type = types.lines; default = ''generator { }''; description = "Logstash input configuration."; example = '' # Read from journal pipe { command => "''${pkgs.systemd}/bin/journalctl -f -o json" type => "syslog" codec => json {} } ''; }; filterConfig = mkOption { type = types.lines; default = ""; description = "logstash filter configuration."; example = '' if [type] == "syslog" { # Keep only relevant systemd fields # http://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 = "Logstash output configuration."; example = '' redis { host => ["localhost"] data_type => "list" key => "logstash" codec => json } elasticsearch { } ''; }; extraSettings = mkOption { type = types.lines; default = ""; description = "Extra Logstash settings in YAML format."; example = '' pipeline: batch: size: 125 delay: 5 ''; }; }; }; ###### implementation config = mkIf cfg.enable { systemd.services.logstash = with pkgs; { description = "Logstash Daemon"; wantedBy = [ "multi-user.target" ]; environment = { JAVA_HOME = jre; }; 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 ${toString cfg.filterWorkers}" (ops havePluginPath pluginsPath) "${verbosityFlag}" "-f ${logstashConf}" "--path.settings ${logstashSettingsDir}" "--path.data ${cfg.dataDir}" ]); }; }; }; }