Merge pull request #15620 from Cornu/mosquitto

mosquitto service: init

nixos/modules/misc/ids.nix

···
       graylog = 243;
       sniproxy = 244;
       nzbget = 245;
+      mosquitto = 246;
 
       # When adding a uid, make sure it doesn't match an existing gid. And don't use uids above 399!
 
···
       emby = 242;
       sniproxy = 244;
       nzbget = 245;
+      mosquitto = 246;
 
       # 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

···
   ./services/networking/mjpg-streamer.nix
   ./services/networking/minidlna.nix
   ./services/networking/miniupnpd.nix
+  ./services/networking/mosquitto.nix
   ./services/networking/mstpd.nix
   ./services/networking/murmur.nix
   ./services/networking/namecoind.nix

nixos/modules/services/networking/mosquitto.nix

···
+{ config, lib, pkgs, ...}:
+
+with lib;
+
+let
+  cfg = config.services.mosquitto;
+
+  listenerConf = optionalString cfg.ssl.enable ''
+    listener ${toString cfg.ssl.port} ${cfg.ssl.host}
+    cafile ${cfg.ssl.cafile}
+    certfile ${cfg.ssl.certfile}
+    keyfile ${cfg.ssl.keyfile}
+  '';
+
+  mosquittoConf = pkgs.writeText "mosquitto.conf" ''
+    pid_file /run/mosquitto/pid
+    acl_file ${aclFile}
+    persistence true
+    allow_anonymous ${if cfg.allowAnonymous then "true" else "false"}
+    bind_address ${cfg.host}
+    port ${toString cfg.port}
+    ${listenerConf}
+    ${cfg.extraConf}
+  '';
+
+  userAcl = (concatStringsSep "\n\n" (mapAttrsToList (n: c:
+    "user ${n}\n" + (concatStringsSep "\n" c.acl)) cfg.users
+  ));
+
+  aclFile = pkgs.writeText "mosquitto.acl" ''
+    ${cfg.aclExtraConf}
+    ${userAcl}
+  '';
+
+in
+
+{
+
+  ###### Interface
+
+  options = {
+    services.mosquitto = {
+      enable = mkEnableOption "Enable the MQTT Mosquitto broker.";
+
+      host = mkOption {
+        default = "127.0.0.1";
+        example = "0.0.0.0";
+        type = types.string;
+        description = ''
+          Host to listen on without SSL.
+        '';
+      };
+
+      port = mkOption {
+        default = 1883;
+        example = 1883;
+        type = types.int;
+        description = ''
+          Port on which to listen without SSL.
+        '';
+      };
+
+      ssl = {
+        enable = mkEnableOption "Enable SSL listener.";
+
+        cafile = mkOption {
+          type = types.nullOr types.path;
+          default = null;
+          description = "Path to PEM encoded CA certificates.";
+        };
+
+        certfile = mkOption {
+          type = types.nullOr types.path;
+          default = null;
+          description = "Path to PEM encoded server certificate.";
+        };
+
+        keyfile = mkOption {
+          type = types.nullOr types.path;
+          default = null;
+          description = "Path to PEM encoded server key.";
+        };
+
+        host = mkOption {
+          default = "0.0.0.0";
+          example = "localhost";
+          type = types.string;
+          description = ''
+            Host to listen on with SSL.
+          '';
+        };
+
+        port = mkOption {
+          default = 8883;
+          example = 8883;
+          type = types.int;
+          description = ''
+            Port on which to listen with SSL.
+          '';
+        };
+      };
+
+      dataDir = mkOption {
+        default = "/var/lib/mosquitto";
+        type = types.path;
+        description = ''
+          The data directory.
+        '';
+      };
+
+      users = mkOption {
+        type = types.attrsOf (types.submodule {
+          options = {
+            password = mkOption {
+              type = with types; uniq (nullOr str);
+              default = null;
+              description = ''
+                Specifies the (clear text) password for the MQTT User.
+              '';
+            };
+
+            hashedPassword = mkOption {
+              type = with types; uniq (nullOr str);
+              default = null;
+              description = ''
+                Specifies the hashed password for the MQTT User.
+                <option>hashedPassword</option> overrides <option>password</option>.
+                To generate hashed password install <literal>mkpasswd</literal>
+                package and run <literal>mkpasswd -m sha-512</literal>.
+              '';
+            };
+
+            acl = mkOption {
+              type = types.listOf types.string;
+              example = [ "topic read A/B" "topic A/#" ];
+              description = ''
+                Control client access to topics on the broker.
+              '';
+            };
+          };
+        });
+        example = { john = { password = "123456"; acl = [ "topic readwrite john/#" ]; }; };
+        description = ''
+          A set of users and their passwords and ACLs.
+        '';
+      };
+
+      allowAnonymous = mkOption {
+        default = false;
+        example = true;
+        type = types.bool;
+        description = ''
+          Allow clients to connect without authentication.
+        '';
+      };
+
+      extraConf = mkOption {
+        default = "";
+        type = types.lines;
+        description = ''
+          Extra config to append to `mosquitto.conf` file.
+        '';
+      };
+
+      aclExtraConf = mkOption {
+        default = "";
+        type = types.lines;
+        description = ''
+          Extra config to prepend to the ACL file.
+        '';
+      };
+
+    };
+  };
+
+
+  ###### Implementation
+
+  config = mkIf cfg.enable {
+
+    systemd.services.mosquitto = {
+      description = "Mosquitto MQTT Broker Daemon";
+      wantedBy = [ "multi-user.target" ];
+      after = [ "network.target" ];
+      serviceConfig = {
+        Type = "forking";
+        User = "mosquitto";
+        Group = "mosquitto";
+        RuntimeDirectory = "mosquitto";
+        WorkingDirectory = cfg.dataDir;
+        Restart = "on-failure";
+        ExecStart = "${pkgs.mosquitto}/bin/mosquitto -c ${mosquittoConf} -d";
+        ExecReload = "${pkgs.coreutils}/bin/kill -HUP $MAINPID";
+        PIDFile = "/run/mosquitto/pid";
+      };
+      preStart = ''
+        rm -f ${cfg.dataDir}/passwd
+        touch ${cfg.dataDir}/passwd
+      '' + concatStringsSep "\n" (
+        mapAttrsToList (n: c:
+          if c.hashedPassword != null then
+            "echo '${n}:${c.hashedPassword}' > ${cfg.dataDir}/passwd"
+          else optionalString (c.password != null)
+            "${pkgs.mosquitto}/bin/mosquitto_passwd -b ${cfg.dataDir}/passwd ${n} ${c.password}"
+        ) cfg.users);
+    };
+
+    users.extraUsers.mosquitto = {
+      description = "Mosquitto MQTT Broker Daemon owner";
+      group = "mosquitto";
+      uid = config.ids.uids.mosquitto;
+      home = cfg.dataDir;
+      createHome = true;
+    };
+
+    users.extraGroups.mosquitto.gid = config.ids.gids.mosquitto;
+
+  };
+}