1 files changed, 131 insertions, 0 deletions
diff --git a/nixos/modules/services/networking/aria2.nix b/nixos/modules/services/networking/aria2.nix
new file mode 100644
index 00000000000..156fef14479
--- /dev/null
+++ b/nixos/modules/services/networking/aria2.nix
@@ -0,0 +1,131 @@
+{ config, lib, pkgs, ... }:
+
+with lib;
+
+let
+  cfg = config.services.aria2;
+
+  homeDir = "/var/lib/aria2";
+
+  settingsDir = "${homeDir}";
+  sessionFile = "${homeDir}/aria2.session";
+  downloadDir = "${homeDir}/Downloads";
+
+  rangesToStringList = map (x: builtins.toString x.from +"-"+ builtins.toString x.to);
+
+  settingsFile = pkgs.writeText "aria2.conf"
+  ''
+    dir=${cfg.downloadDir}
+    listen-port=${concatStringsSep "," (rangesToStringList cfg.listenPortRange)}
+    rpc-listen-port=${toString cfg.rpcListenPort}
+    rpc-secret=${cfg.rpcSecret}
+  '';
+
+in
+{
+  options = {
+    services.aria2 = {
+      enable = mkOption {
+        type = types.bool;
+        default = false;
+        description = ''
+          Whether or not to enable the headless Aria2 daemon service.
+
+          Aria2 daemon can be controlled via the RPC interface using
+          one of many WebUI (http://localhost:6800/ by default).
+
+          Targets are downloaded to ${downloadDir} by default and are
+          accessible to users in the "aria2" group.
+        '';
+      };
+      openPorts = mkOption {
+        type = types.bool;
+        default = false;
+        description = ''
+          Open listen and RPC ports found in listenPortRange and rpcListenPort
+          options in the firewall.
+        '';
+      };
+      downloadDir = mkOption {
+        type = types.path;
+        default = downloadDir;
+        description = ''
+          Directory to store downloaded files.
+        '';
+      };
+      listenPortRange = mkOption {
+        type = types.listOf types.attrs;
+        default = [ { from = 6881; to = 6999; } ];
+        description = ''
+          Set UDP listening port range used by DHT(IPv4, IPv6) and UDP tracker.
+        '';
+      };
+      rpcListenPort = mkOption {
+        type = types.int;
+        default = 6800;
+        description = "Specify a port number for JSON-RPC/XML-RPC server to listen to. Possible Values: 1024-65535";
+      };
+      rpcSecret = mkOption {
+        type = types.str;
+        default = "aria2rpc";
+        description = ''
+          Set RPC secret authorization token.
+          Read https://aria2.github.io/manual/en/html/aria2c.html#rpc-auth to know how this option value is used.
+        '';
+      };
+      extraArguments = mkOption {
+        type = types.separatedString " ";
+        example = "--rpc-listen-all --remote-time=true";
+        default = "";
+        description = ''
+          Additional arguments to be passed to Aria2.
+        '';
+      };
+    };
+  };
+
+  config = mkIf cfg.enable {
+
+    # Need to open ports for proper functioning
+    networking.firewall = mkIf cfg.openPorts {
+      allowedUDPPortRanges = config.services.aria2.listenPortRange;
+      allowedTCPPorts = [ config.services.aria2.rpcListenPort ];
+    };
+
+    users.users.aria2 = {
+      group = "aria2";
+      uid = config.ids.uids.aria2;
+      description = "aria2 user";
+      home = homeDir;
+      createHome = false;
+    };
+
+    users.groups.aria2.gid = config.ids.gids.aria2;
+
+    systemd.tmpfiles.rules = [
+      "d '${homeDir}' 0770 aria2 aria2 - -"
+      "d '${config.services.aria2.downloadDir}' 0770 aria2 aria2 - -"
+    ];
+
+    systemd.services.aria2 = {
+      description = "aria2 Service";
+      after = [ "network.target" ];
+      wantedBy = [ "multi-user.target" ];
+      preStart = ''
+        if [[ ! -e "${sessionFile}" ]]
+        then
+          touch "${sessionFile}"
+        fi
+        cp -f "${settingsFile}" "${settingsDir}/aria2.conf"
+      '';
+
+      serviceConfig = {
+        Restart = "on-abort";
+        ExecStart = "${pkgs.aria2}/bin/aria2c --enable-rpc --conf-path=${settingsDir}/aria2.conf ${config.services.aria2.extraArguments} --save-session=${sessionFile}";
+        ExecReload = "${pkgs.coreutils}/bin/kill -HUP $MAINPID";
+        User = "aria2";
+        Group = "aria2";
+      };
+    };
+  };
+}