mattermost service: init

nixos/modules/misc/ids.nix

···
       gocd-agent = 251;
       gocd-server = 252;
       terraria = 253;
+      mattermost = 254;
 
       # When adding a uid, make sure it doesn't match an existing gid. And don't use uids above 399!
 
···
       gocd-agent = 251;
       gocd-server = 252;
       terraria = 253;
+      mattermost = 254;
 
       # 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/ttys/agetty.nix
   ./services/ttys/gpm.nix
   ./services/ttys/kmscon.nix
+  ./services/web-apps/mattermost.nix
   ./services/web-apps/pump.io.nix
   ./services/web-apps/tt-rss.nix
   ./services/web-servers/apache-httpd/default.nix

nixos/modules/services/web-apps/mattermost.nix

···
+{ config, pkgs, lib, ... }:
+
+with lib;
+
+let
+
+  cfg = config.services.mattermost;
+
+  defaultConfig = builtins.fromJSON (readFile "${pkgs.mattermost}/config/config.json");
+
+  mattermostConf = foldl recursiveUpdate defaultConfig
+    [ { ServiceSettings.SiteURL = cfg.siteUrl;
+        ServiceSettings.ListenAddress = cfg.listenAddress;
+        TeamSettings.SiteName = cfg.siteName;
+        SqlSettings.DriverName = "postgres";
+        SqlSettings.DataSource = "postgres://${cfg.localDatabaseUser}:${cfg.localDatabasePassword}@localhost:5432/${cfg.localDatabaseName}?sslmode=disable&connect_timeout=10";
+      }
+      cfg.extraConfig
+    ];
+
+  mattermostConfJSON = pkgs.writeText "mattermost-config-raw.json" (builtins.toJSON mattermostConf);
+
+in
+
+{
+  options = {
+    services.mattermost = {
+      enable = mkEnableOption "Mattermost chat platform";
+
+      statePath = mkOption {
+        type = types.str;
+        default = "/var/lib/mattermost";
+        description = "Mattermost working directory";
+      };
+
+      siteUrl = mkOption {
+        type = types.str;
+        example = "https://chat.example.com";
+        description = ''
+          URL this Mattermost instance is reachable under, without trailing slash."
+        '';
+      };
+
+      siteName = mkOption {
+        type = types.str;
+        default = "Mattermost";
+        description = "Name of this Mattermost site.";
+      };
+
+      listenAddress = mkOption {
+        type = types.str;
+        default = ":8065";
+        example = "[::1]:8065";
+        description = ''
+          Address and port this Mattermost instance listens to.
+        '';
+      };
+
+      mutableConfig = mkOption {
+        type = types.bool;
+        default = false;
+        description = ''
+          Whether the Mattermost config.json is writeable by Mattermost.
+
+          Most of the settings can be edited in the system console of
+          Mattermost if this option is enabled. A template config using
+          the options specified in services.mattermost will be generated
+          but won't be overwritten on changes or rebuilds.
+
+          If this option is disabled, changes in the system console won't
+          be possible (default). If an config.json is present, it will be
+          overwritten!
+        '';
+      };
+
+      extraConfig = mkOption {
+        type = types.attrs;
+        default = { };
+        description = ''
+          Addtional configuration options as Nix attribute set in config.json schema.
+        '';
+      };
+
+      localDatabaseCreate = mkOption {
+        type = types.bool;
+        default = true;
+        description = ''
+          Create a local PostgreSQL database for Mattermost automatically.
+        '';
+      };
+
+      localDatabaseName = mkOption {
+        type = types.str;
+        default = "mattermost";
+        description = ''
+          Local Mattermost database name.
+        '';
+      };
+
+      localDatabaseUser = mkOption {
+        type = types.str;
+        default = "mattermost";
+        description = ''
+          Local Mattermost database username.
+        '';
+      };
+
+      localDatabasePassword = mkOption {
+        type = types.str;
+        default = "mmpgsecret";
+        description = ''
+          Password for local Mattermost database user.
+        '';
+      };
+
+      user = mkOption {
+        type = types.str;
+        default = "mattermost";
+        description = ''
+          User which runs the Mattermost service.
+        '';
+      };
+
+      group = mkOption {
+        type = types.str;
+        default = "mattermost";
+        description = ''
+          Group which runs the Mattermost service.
+        '';
+      };
+
+      matterircd = {
+        enable = mkEnableOption "Mattermost IRC bridge";
+        parameters = mkOption {
+          type = types.listOf types.str;
+          default = [ ];
+          example = [ "-mmserver chat.example.com" "-bind [::]:6667" ];
+          description = ''
+            Set commandline parameters to pass to matterircd. See
+            https://github.com/42wim/matterircd#usage for more information.
+          '';
+        };
+      };
+    };
+  };
+
+  config = mkMerge [
+    (mkIf cfg.enable {
+      users.extraUsers = optionalAttrs (cfg.user == "mattermost") (singleton {
+        name = "mattermost";
+        group = cfg.group;
+        uid = config.ids.uids.mattermost;
+        home = cfg.statePath;
+      });
+
+      users.extraGroups = optionalAttrs (cfg.group == "mattermost") (singleton {
+        name = "mattermost";
+        gid = config.ids.gids.mattermost;
+      });
+
+      services.postgresql.enable = cfg.localDatabaseCreate;
+
+      # The systemd service will fail to execute the preStart hook
+      # if the WorkingDirectory does not exist
+      system.activationScripts.mattermost = ''
+        mkdir -p ${cfg.statePath}
+      '';
+
+      systemd.services.mattermost = {
+        description = "Mattermost chat platform service";
+        wantedBy = [ "multi-user.target" ];
+        after = [ "network.target" "postgresql.service" ];
+
+        preStart = ''
+          mkdir -p ${cfg.statePath}/{data,config,logs}
+          ln -sf ${pkgs.mattermost}/{bin,fonts,i18n,templates,webapp} ${cfg.statePath}
+        '' + lib.optionalString (!cfg.mutableConfig) ''
+          ln -sf ${mattermostConfJSON} ${cfg.statePath}/config/config.json
+        '' + lib.optionalString cfg.mutableConfig ''
+          if ! test -e "${cfg.statePath}/config/.initial-created"; then
+            rm -f ${cfg.statePath}/config/config.json
+            cp ${mattermostConfJSON} ${cfg.statePath}/config/config.json
+            touch ${cfg.statePath}/config/.initial-created
+          fi
+        '' + lib.optionalString cfg.localDatabaseCreate ''
+          if ! test -e "${cfg.statePath}/.db-created"; then
+            ${config.services.postgresql.package}/bin/psql postgres -c \
+              "CREATE ROLE ${cfg.localDatabaseUser} WITH LOGIN NOCREATEDB NOCREATEROLE NOCREATEUSER ENCRYPTED PASSWORD '${cfg.localDatabasePassword}'"
+            ${config.services.postgresql.package}/bin/createdb \
+              --owner ${cfg.localDatabaseUser} ${cfg.localDatabaseName}
+            touch ${cfg.statePath}/.db-created
+          fi
+        '' + ''
+          chown ${cfg.user}:${cfg.group} -R ${cfg.statePath}
+          chmod u+rw,g+r,o-rwx -R ${cfg.statePath}
+        '';
+
+        serviceConfig = {
+          PermissionsStartOnly = true;
+          User = cfg.user;
+          Group = cfg.group;
+          ExecStart = "${pkgs.mattermost}/bin/mattermost-platform";
+          WorkingDirectory = "${cfg.statePath}";
+          PrivateTmp = true;
+          Restart = "always";
+          RestartSec = "10";
+          LimitNOFILE = "49152";
+        };
+      };
+    })
+    (mkIf cfg.matterircd.enable {
+      systemd.services.matterircd = {
+        description = "Mattermost IRC bridge service";
+        wantedBy = [ "multi-user.target" ];
+        serviceConfig = {
+          User = "nobody";
+          Group = "nogroup";
+          ExecStart = "${pkgs.matterircd.bin}/bin/matterircd ${concatStringsSep " " cfg.matterircd.parameters}";
+          WorkingDirectory = "/tmp";
+          PrivateTmp = true;
+          Restart = "always";
+          RestartSec = "5";
+        };
+      };
+    })
+  ];
+}
+