nixos/druid: init module

nixos/modules/module-list.nix

@@ -389,6 +389,7 @@
   ./services/blockchain/ethereum/geth.nix
   ./services/blockchain/ethereum/lighthouse.nix
   ./services/cluster/corosync/default.nix
+  ./services/cluster/druid/default.nix
   ./services/cluster/hadoop/default.nix
   ./services/cluster/k3s/default.nix
   ./services/cluster/kubernetes/addon-manager.nix

nixos/modules/services/cluster/druid/default.nix

@@ -0,0 +1,296 @@
+{
+  config,
+  lib,
+  pkgs,
+  ...
+}:
+let
+  cfg = config.services.druid;
+  inherit (lib)
+    concatStrings
+    concatStringsSep
+    mapAttrsToList
+    concatMap
+    attrByPath
+    mkIf
+    mkMerge
+    mkEnableOption
+    mkOption
+    types
+    mkPackageOption
+    ;
+
+  druidServiceOption = serviceName: {
+    enable = mkEnableOption serviceName;
+
+    restartIfChanged = mkOption {
+      type = types.bool;
+      description = ''
+        Automatically restart the service on config change.
+        This can be set to false to defer restarts on clusters running critical applications.
+        Please consider the security implications of inadvertently running an older version,
+        and the possibility of unexpected behavior caused by inconsistent versions across a cluster when disabling this option.
+      '';
+      default = false;
+    };
+
+    config = mkOption {
+      default = { };
+      type = types.attrsOf types.anything;
+      description = ''
+        (key=value) Configuration to be written to runtime.properties of the druid ${serviceName}
+        <https://druid.apache.org/docs/latest/configuration/index.html>
+      '';
+      example = {
+        "druid.plainTextPort" = "8082";
+        "druid.service" = "servicename";
+      };
+    };
+
+    jdk = mkPackageOption pkgs "JDK" { default = [ "jdk17_headless" ]; };
+
+    jvmArgs = mkOption {
+      type = types.str;
+      default = "";
+      description = "Arguments to pass to the JVM";
+    };
+
+    openFirewall = mkOption {
+      type = types.bool;
+      default = false;
+      description = "Open firewall ports for ${serviceName}.";
+    };
+
+    internalConfig = mkOption {
+      default = { };
+      type = types.attrsOf types.anything;
+      internal = true;
+      description = "Internal Option to add to runtime.properties for ${serviceName}.";
+    };
+  };
+
+  druidServiceConfig =
+    {
+      name,
+      serviceOptions ? cfg."${name}",
+      allowedTCPPorts ? [ ],
+      tmpDirs ? [ ],
+      extraConfig ? { },
+    }:
+    (mkIf serviceOptions.enable (mkMerge [
+      {
+        systemd = {
+          services."druid-${name}" = {
+            after = [ "network.target" ];
+
+            description = "Druid ${name}";
+
+            wantedBy = [ "multi-user.target" ];
+
+            inherit (serviceOptions) restartIfChanged;
+
+            path = [
+              cfg.package
+              serviceOptions.jdk
+            ];
+
+            script =
+              let
+                cfgFile =
+                  fileName: properties:
+                  pkgs.writeTextDir fileName (
+                    concatStringsSep "\n" (mapAttrsToList (n: v: "${n}=${toString v}") properties)
+                  );
+
+                commonConfigFile = cfgFile "common.runtime.properties" cfg.commonConfig;
+
+                configFile = cfgFile "runtime.properties" (serviceOptions.config // serviceOptions.internalConfig);
+
+                extraClassPath = concatStrings (map (path: ":" + path) cfg.extraClassPaths);
+
+                extraConfDir = concatStrings (map (dir: ":" + dir + "/*") cfg.extraConfDirs);
+              in
+              ''
+                run-java -Dlog4j.configurationFile=file:${cfg.log4j} \
+                  -Ddruid.extensions.directory=${cfg.package}/extensions \
+                  -Ddruid.extensions.hadoopDependenciesDir=${cfg.package}/hadoop-dependencies \
+                  -classpath  ${commonConfigFile}:${configFile}:${cfg.package}/lib/\*${extraClassPath}${extraConfDir} \
+                  ${serviceOptions.jvmArgs} \
+                  org.apache.druid.cli.Main server ${name}
+              '';
+
+            serviceConfig = {
+              User = "druid";
+              SyslogIdentifier = "druid-${name}";
+              Restart = "always";
+            };
+          };
+
+          tmpfiles.rules = concatMap (x: [ "d ${x} 0755 druid druid" ]) (cfg.commonTmpDirs ++ tmpDirs);
+        };
+        networking.firewall.allowedTCPPorts = mkIf (attrByPath [
+          "openFirewall"
+        ] false serviceOptions) allowedTCPPorts;
+
+        users = {
+          users.druid = {
+            description = "Druid user";
+            group = "druid";
+            isNormalUser = true;
+          };
+          groups.druid = { };
+        };
+      }
+      extraConfig
+    ]));
+in
+{
+  options.services.druid = {
+    package = mkPackageOption pkgs "apache-druid" { default = [ "druid" ]; };
+
+    commonConfig = mkOption {
+      default = { };
+
+      type = types.attrsOf types.anything;
+
+      description = "(key=value) Configuration to be written to common.runtime.properties";
+
+      example = {
+        "druid.zk.service.host" = "localhost:2181";
+        "druid.metadata.storage.type" = "mysql";
+        "druid.metadata.storage.connector.connectURI" = "jdbc:mysql://localhost:3306/druid";
+        "druid.extensions.loadList" = ''[ "mysql-metadata-storage" ]'';
+      };
+    };
+
+    commonTmpDirs = mkOption {
+      default = [ "/var/log/druid/requests" ];
+      type = types.listOf types.str;
+      description = "Common List of directories used by druid processes";
+    };
+
+    log4j = mkOption {
+      type = types.path;
+      description = "Log4j Configuration for the druid process";
+    };
+
+    extraClassPaths = mkOption {
+      default = [ ];
+      type = types.listOf types.str;
+      description = "Extra classpath to include in the jvm";
+    };
+
+    extraConfDirs = mkOption {
+      default = [ ];
+      type = types.listOf types.path;
+      description = "Extra Conf Dirs to include in the jvm";
+    };
+
+    overlord = druidServiceOption "Druid Overlord";
+
+    coordinator = druidServiceOption "Druid Coordinator";
+
+    broker = druidServiceOption "Druid Broker";
+
+    historical = (druidServiceOption "Druid Historical") // {
+      segmentLocations = mkOption {
+
+        default = null;
+
+        description = "Locations where the historical will store its data.";
+
+        type =
+          with types;
+          nullOr (
+            listOf (submodule {
+              options = {
+                path = mkOption {
+                  type = path;
+                  description = "the path to store the segments";
+                };
+
+                maxSize = mkOption {
+                  type = str;
+                  description = "Max size the druid historical can occupy";
+                };
+
+                freeSpacePercent = mkOption {
+                  type = float;
+                  default = 1.0;
+                  description = "Druid Historical will fail to write if it exceeds this value";
+                };
+              };
+            })
+          );
+
+      };
+    };
+
+    middleManager = druidServiceOption "Druid middleManager";
+    router = druidServiceOption "Druid Router";
+  };
+  config = mkMerge [
+    (druidServiceConfig rec {
+      name = "overlord";
+      allowedTCPPorts = [ (attrByPath [ "druid.plaintextPort" ] 8090 cfg."${name}".config) ];
+    })
+
+    (druidServiceConfig rec {
+      name = "coordinator";
+      allowedTCPPorts = [ (attrByPath [ "druid.plaintextPort" ] 8081 cfg."${name}".config) ];
+    })
+
+    (druidServiceConfig rec {
+      name = "broker";
+
+      tmpDirs = [ (attrByPath [ "druid.lookup.snapshotWorkingDir" ] "" cfg."${name}".config) ];
+
+      allowedTCPPorts = [ (attrByPath [ "druid.plaintextPort" ] 8082 cfg."${name}".config) ];
+    })
+
+    (druidServiceConfig rec {
+      name = "historical";
+
+      tmpDirs = [
+        (attrByPath [ "druid.lookup.snapshotWorkingDir" ] "" cfg."${name}".config)
+      ] ++ (map (x: x.path) cfg."${name}".segmentLocations);
+
+      allowedTCPPorts = [ (attrByPath [ "druid.plaintextPort" ] 8083 cfg."${name}".config) ];
+
+      extraConfig.services.druid.historical.internalConfig."druid.segmentCache.locations" = builtins.toJSON cfg.historical.segmentLocations;
+    })
+
+    (druidServiceConfig rec {
+      name = "middleManager";
+
+      tmpDirs = [
+        "/var/log/druid/indexer"
+      ] ++ [ (attrByPath [ "druid.indexer.task.baseTaskDir" ] "" cfg."${name}".config) ];
+
+      allowedTCPPorts = [ (attrByPath [ "druid.plaintextPort" ] 8091 cfg."${name}".config) ];
+
+      extraConfig = {
+        services.druid.middleManager.internalConfig = {
+          "druid.indexer.runner.javaCommand" = "${cfg.middleManager.jdk}/bin/java";
+          "druid.indexer.runner.javaOpts" =
+            (attrByPath [ "druid.indexer.runner.javaOpts" ] "" cfg.middleManager.config)
+            + " -Dlog4j.configurationFile=file:${cfg.log4j}";
+        };
+
+        networking.firewall.allowedTCPPortRanges = mkIf cfg.middleManager.openFirewall [
+          {
+            from = attrByPath [ "druid.indexer.runner.startPort" ] 8100 cfg.middleManager.config;
+            to = attrByPath [ "druid.indexer.runner.endPort" ] 65535 cfg.middleManager.config;
+          }
+        ];
+      };
+    })
+
+    (druidServiceConfig rec {
+      name = "router";
+
+      allowedTCPPorts = [ (attrByPath [ "druid.plaintextPort" ] 8888 cfg."${name}".config) ];
+    })
+  ];
+
+}