Merge branch 'allow-more-modules' into 'main'

modules: allow for more modules to be added

See merge request coffeetables/nix-matrix-appservices!5

3 files changed, 484 insertions, 0 deletions

diff --git a/modules/matrix-appservices/as-formats.nix b/modules/matrix-appservices/as-formats.nix
new file mode 100644
index 0000000..fa7a4cf
--- /dev/null
+++ b/modules/matrix-appservices/as-formats.nix
@@ -0,0 +1,160 @@
+{ name, systemConfig, asConfig, lib, pkgs, ... }:
+
+with lib;
+let
+  inherit (systemConfig.services.matrix-appservices)
+    homeserverURL
+    homeserverDomain;
+  package = asConfig.package;
+  pname = getName package;
+  command = "${package}/bin/${pname}";
+
+  mautrix = {
+    startupScript = ''
+      ${command} --config=$SETTINGS_FILE \
+        --registration=$REGISTRATION_FILE
+    '';
+
+    settings = {
+      homeserver = {
+        address = homeserverURL;
+        domain = homeserverDomain;
+      };
+
+      appservice = with asConfig; {
+        address = "http://${host}:${toString port}";
+
+        hostname = host;
+        inherit port;
+
+        state_store_path = "$DIR/mx-state.json";
+        # mautrix stores the registration tokens in the config file
+        as_token = "$AS_TOKEN";
+        hs_token = "$HS_TOKEN";
+      };
+
+      bridge = {
+        username_template = "${name}_{userid}";
+        permissions = {
+          ${homeserverDomain} = "user";
+        };
+      };
+    };
+  };
+
+in
+{
+  other = {
+    description = ''
+      No defaults will be set.
+    '';
+  };
+
+  matrix-appservice = {
+    startupScript = ''
+      ${command} \
+        --config=$SETTINGS_FILE \
+        --port=$(echo ${asConfig.listenAddress} | sed 's/.*://') \
+        --file=$REGISTRATION_FILE
+    '';
+
+    description = ''
+      For bridges based on the matrix-appservice-bridge library. The settings for these
+      bridges are NOT configured automatically, because of the various differences
+      between them.
+    '';
+  };
+
+  mx-puppet = {
+    startupScript = ''
+      ${command} \
+        --config=$SETTINGS_FILE \
+        --registration-file=$REGISTRATION_FILE
+    '';
+
+    registrationData =
+      let
+        # mx-puppet virtual users are always created based on the package name
+        botName = removePrefix "mx-puppet-" pname;
+      in
+      {
+        id = "${botName}-puppet";
+        sender_localpart = "_${botName}puppet_bot";
+        protocols = [ ];
+        namespaces = {
+          rooms = [ ];
+          users = [
+            {
+              regex = "@_${botName}puppet_.*:${homeserverDomain}";
+              exclusive = true;
+            }
+          ];
+          aliases = [
+            {
+              regex = "#_${botName}puppet_.*:${homeserverDomain}";
+              exclusive = true;
+            }
+          ];
+        };
+      };
+
+    settings = {
+      bridge = {
+        inherit (asConfig) port;
+        bindAddress = asConfig.host;
+        domain = homeserverDomain;
+        homeserverUrl = homeserverURL;
+      };
+      database.filename = "$DIR/database.db";
+      provisioning.whitelist = [ "@.*:${homeserverDomain}" ];
+      relay.whitelist = [ "@.*:${homeserverDomain}" ];
+      selfService.whitelist = [ "@.*:${homeserverDomain}" ];
+      logging = {
+        lineDateFormat = "";
+        files = [ ];
+      };
+    };
+
+    serviceConfig.WorkingDirectory =
+      "${package}/lib/node_modules/${pname}";
+
+    description = ''
+      For bridges based on the mx-puppet-bridge library. The settings will be
+      configured to use a sqlite database. Make sure to override database.filename,
+      if you plan to use another database.
+    '';
+
+  };
+
+  mautrix-go = {
+    inherit (mautrix) startupScript;
+
+    settings = recursiveUpdate mautrix.settings {
+      bridge.username_template = "${name}_{{.}}";
+      appservice.database = {
+        type = "sqlite3";
+        uri = "$DIR/database.db";
+      };
+    };
+
+    description = ''
+      The settings are configured to use a sqlite database. The startupScript will
+      create a new config file on every run to set the tokens, because mautrix
+      requires them to be in the config file.
+    '';
+  };
+
+  mautrix-python = {
+    settings = recursiveUpdate mautrix.settings {
+      appservice.database = "sqlite:///$DIR/database.db";
+    };
+
+    startupScript = optionalString (package ? alembic)
+      "${package.alembic}/bin/alembic -x config=$SETTINGS_FILE upgrade head\n"
+    + mautrix.startupScript;
+    description = ''
+      Same properties as mautrix-go. This will also upgrade the database on every run
+    '';
+  };
+
+}
diff --git a/modules/matrix-appservices/as-options.nix b/modules/matrix-appservices/as-options.nix
new file mode 100644
index 0000000..2afbbbf
--- /dev/null
+++ b/modules/matrix-appservices/as-options.nix
@@ -0,0 +1,144 @@
+{ systemConfig, lib, pkgs, ... }:
+with lib;
+types.submodule ({ config, name, ... }:
+  let
+    inherit (systemConfig.services.matrix-appservices)
+      homeserverDomain;
+
+    asFormats = (import ./as-formats.nix) {
+      inherit name lib pkgs systemConfig;
+      asConfig = config;
+    };
+    asFormat = asFormats.${config.format};
+    settingsFormat = pkgs.formats.json { };
+  in
+  {
+    options = rec {
+
+      format = mkOption {
+        type = types.enum (mapAttrsToList (n: _: n) asFormats);
+        default = "other";
+        description = ''
+          Format of the appservice, used to set option defaults for appservice.
+          This is usually determined by the library the appservice is based on.
+
+          Below are descriptions for each format
+
+        '' + (concatStringsSep "\n" (mapAttrsToList
+          (n: v: "${n}: ${v.description}")
+          asFormats));
+      };
+
+      package = mkOption {
+        type = types.nullOr types.package;
+        default = null;
+        example = "pkgs.mautrix-whatsapp";
+        description = ''
+          The package for the appservice. Used by formats except 'other'.
+          This is unecessary if startupScript is set.
+        '';
+      };
+
+      settings = mkOption rec {
+        type = settingsFormat.type;
+        apply = recursiveUpdate default;
+        default = asFormat.settings or { };
+        defaultText = "Format will attempt to configure database and allow homeserver users";
+        example = literalExpression ''
+          {
+            bridge = {
+              domain = "public-domain.tld";
+              homeserverUrl = "http://public-domain.tld:8008";
+            };
+          }
+        '';
+        description = ''
+          Appservice configuration as a Nix attribute set.
+          All environment variables will be substituted.
+          Including:
+            - $DIR which refers to the appservice's data directory.
+            - $AS_TOKEN, $HS_TOKEN which refers to the Appservice and
+                Homeserver registration tokens.
+
+          Secret tokens, should be specified in serviceConfig.EnvironmentFile
+          instead of this world-readable attribute set.
+
+          Configuration options should match those described as per your appservice's settings
+          Check out the confg sample for this.
+
+        '';
+      };
+
+      registrationData = mkOption {
+        type = settingsFormat.type;
+        default = asFormat.registrationData or {
+          namespaces = {
+            users = [
+              {
+                regex = "@${name}_.*:${homeserverDomain}";
+                exclusive = true;
+              }
+              {
+                regex = "@${name}bot:${homeserverDomain}";
+                exclusive = true;
+              }
+            ];
+          };
+        };
+        defaultText = ''
+          Reserve usernames under the homeserver that start with
+          this appservice's name followed by an _ or "bot"
+        '';
+        description = ''
+          Data to set in the registration file for the appservice. The default
+          set or the format should usually deal with this.
+        '';
+      };
+
+      host = mkOption {
+        type = types.str;
+        default = "localhost";
+        description = ''
+          The host the appservice will listen on.
+          Will need to specified in config, but most formats will do it for you using
+          this option.
+        '';
+      };
+
+      port = mkOption {
+        type = types.port;
+        description = ''
+          The port the appservice will listen on.
+          Will need to specified in config, but most formats will do it for you using
+          this option.
+        '';
+      };
+
+      startupScript = mkOption {
+        type = types.str;
+        default = asFormat.startupScript or "";
+        description = ''
+          Script that starts the appservice.
+          The settings file will be available as $SETTINGS_FILE
+          and the registration file as $REGISTRATION_FILE
+        '';
+      };
+
+      serviceConfig = mkOption rec {
+        type = types.attrs;
+        apply = x: default // x;
+        default = asFormat.serviceConfig or { };
+        description = ''
+          Overrides for settings in the service's serviceConfig
+        '';
+      };
+
+      serviceDependencies = mkOption {
+        type = types.listOf types.str;
+        default = [ ];
+        description = ''
+          Services started before this appservice
+        '';
+      };
+    };
+  })
diff --git a/modules/matrix-appservices/default.nix b/modules/matrix-appservices/default.nix
new file mode 100644
index 0000000..f57284d
--- /dev/null
+++ b/modules/matrix-appservices/default.nix
@@ -0,0 +1,180 @@
+{ config, lib, pkgs, ... }:
+
+with lib;
+let
+  cfg = config.services.matrix-appservices;
+  asOpts = import ./as-options.nix {
+    inherit lib pkgs;
+    systemConfig = config;
+  };
+  mkService = name: opts:
+    with opts;
+    let
+      settingsFormat = pkgs.formats.json { };
+      dataDir = "/var/lib/matrix-as-${name}";
+      registrationFile = "${dataDir}/${name}-registration.yaml";
+      # Replace all references to $DIR to the dat directory
+      settingsData = settingsFormat.generate "config.json" settings;
+      settingsFile = "${dataDir}/config.json";
+      serviceDeps = [ "network-online.target" ] ++ serviceDependencies;
+
+      registrationContent = {
+        id = name;
+        url = "http://${host}:${toString port}";
+        as_token = "$AS_TOKEN";
+        hs_token = "$HS_TOKEN";
+        sender_localpart = "$SENDER_LOCALPART";
+        rate_limited = false;
+      } // registrationData;
+    in
+    {
+      description = "A matrix appservice for ${name}.";
+
+      wantedBy = [ "multi-user.target" ];
+      wants = serviceDeps;
+      after = serviceDeps;
+      # Appservices don't need synapse up, but synapse exists if registration files are missing
+      before = mkIf (cfg.homeserver != null) [ "${cfg.homeserver}.service" ];
+
+      path = [ pkgs.yq ];
+      environment = {
+        DIR = dataDir;
+        SETTINGS_FILE = settingsFile;
+        REGISTRATION_FILE = registrationFile;
+      };
+
+      preStart = ''
+        if [ ! -f ${registrationFile} ]; then
+          AS_TOKEN=$(cat /proc/sys/kernel/random/uuid) \
+          HS_TOKEN=$(cat /proc/sys/kernel/random/uuid) \
+          SENDER_LOCALPART=$(cat /proc/sys/kernel/random/uuid) \
+          ${pkgs.envsubst}/bin/envsubst \
+            -i ${settingsFormat.generate "config.json" registrationContent} \
+            -o ${registrationFile}
+
+          chmod 640 ${registrationFile}
+        fi
+
+        AS_TOKEN=$(cat ${registrationFile} | yq .as_token | tr -d '"') \
+        HS_TOKEN=$(cat ${registrationFile} | yq .hs_token | tr -d '"') \
+        ${pkgs.envsubst}/bin/envsubst -i ${settingsData} -o ${settingsFile}
+        chmod 640 ${settingsFile}
+      '';
+
+      script = startupScript;
+
+      serviceConfig = {
+        Type = "simple";
+        Restart = "always";
+
+        ProtectSystem = "strict";
+        PrivateTmp = true;
+        ProtectHome = true;
+        ProtectKernelTunables = true;
+        ProtectKernelModules = true;
+        ProtectControlGroups = true;
+
+        User = "matrix-as-${name}";
+        Group = "matrix-as-${name}";
+        WorkingDirectory = dataDir;
+        StateDirectory = baseNameOf dataDir;
+        StateDirectoryMode = "0750";
+        UMask = 0027;
+      } // opts.serviceConfig;
+    };
+
+in
+{
+  options = {
+    services.matrix-appservices = {
+      services = mkOption {
+        type = types.attrsOf asOpts;
+        default = { };
+        example = literalExpression ''
+          whatsapp = {
+            format = "mautrix-go";
+            package = pkgs.mautrix-whatsapp;
+          };
+        '';
+        description = ''
+          Appservices to setup.
+          Each appservice will be started as a systemd service with the prefix matrix-as.
+          And its data will be stored in /var/lib/matrix-as-name.
+        '';
+      };
+
+      homeserver = mkOption {
+        type = types.enum [ "matrix-synapse" "dendrite" null ];
+        default = "matrix-synapse";
+        description = ''
+          The homeserver software the appservices connect to. This will ensure appservices
+          start after the homeserver and it will be used by the addRegistrationFiles option.
+        '';
+      };
+
+      homeserverURL = mkOption {
+        type = types.str;
+        default = "https://${cfg.homeserverDomain}";
+        description = ''
+          URL of the homeserver the apservices connect to
+        '';
+      };
+
+      homeserverDomain = mkOption {
+        type = types.str;
+        default = if config.networking.domain != null then config.networking.domain else "";
+        defaultText = "\${config.networking.domain}";
+        description = ''
+          Domain of the homeserver the appservices connect to
+        '';
+      };
+
+      addRegistrationFiles = mkOption {
+        type = types.bool;
+        default = false;
+        description = ''
+          Whether to add the application service registration files to the homeserver configuration.
+          It is recommended to verify appservice files, located in /var/lib/matrix-as-*, before adding them
+        '';
+      };
+    };
+  };
+
+  config = mkIf (cfg.services != { }) {
+
+    assertions = mapAttrsToList
+      (n: v: {
+        assertion = v.format == "other" || v.package != null;
+        message = "A package must be provided if a custom format is set";
+      })
+      cfg.services;
+
+    users.users = mapAttrs'
+      (n: v: nameValuePair "matrix-as-${n}" {
+        group = "matrix-as-${n}";
+        isSystemUser = true;
+      })
+      cfg.services;
+    users.groups = mapAttrs' (n: v: nameValuePair "matrix-as-${n}" { }) cfg.services;
+
+    # Create a service for each appservice
+    systemd.services = (mapAttrs' (n: v: nameValuePair "matrix-as-${n}" (mkService n v)) cfg.services) // {
+      # Add the matrix service to the groups of all appservices to give access to the registration file
+      matrix-synapse.serviceConfig.SupplementaryGroups = mapAttrsToList (n: v: "matrix-as-${n}") cfg.services;
+      dendrite.serviceConfig.SupplementaryGroups = mapAttrsToList (n: v: "matrix-as-${n}") cfg.services;
+    };
+
+    services =
+      let
+        registrationFiles = mapAttrsToList (n: _: "/var/lib/matrix-as-${n}/${n}-registration.yaml")
+          (filterAttrs (_: v: v.registrationData != { }) cfg.services);
+      in
+      mkIf cfg.addRegistrationFiles {
+        matrix-synapse.app_service_config_files = mkIf (cfg.homeserver == "matrix-synapse") registrationFiles;
+        dendrite.settings.app_service_api.config_files = mkIf (cfg.homeserver == "dendrite") registrationFiles;
+      };
+  };
+
+  meta.maintainers = with maintainers; [ pacman99 Flakebi ];
+
+}