initial commit

modules/nixos/mcpo/default.nix

@@ -0,0 +1,111 @@
+{
+  config,
+  lib,
+  pkgs,
+  ...
+}:
+
+let
+  cfg = config.services.mcpo;
+
+  configFile = pkgs.writeText "mcpo-config.json" (builtins.toJSON cfg.settings);
+
+  inherit (lib)
+    getExe
+    mkEnableOption
+    mkIf
+    mkOption
+    types
+    ;
+in
+{
+  options.services.mcpo = {
+    enable = mkEnableOption "mcpo, an MCP-to-OpenAPI proxy server.";
+
+    package = mkOption {
+      type = types.nullOr types.package;
+      description = "The package to use for mcpo. You have to specify this manually.";
+      default = null;
+    };
+
+    user = mkOption {
+      type = types.str;
+      description = "The user the mcpo service will run as.";
+      default = "mcpo";
+    };
+
+    group = mkOption {
+      type = types.str;
+      description = "The group the mcpo service will run as.";
+      default = "mcpo";
+    };
+
+    workDir = mkOption {
+      type = types.str;
+      description = "The working directory for the mcpo service.";
+      default = "/var/lib/mcpo";
+    };
+
+    settings = mkOption {
+      type = types.attrs;
+      description = "A set of attributes that will be translated into the JSON configuration file for mcpo. It follows the Claude Desktop format.";
+      default = { };
+      example = {
+        mcpServers = {
+          memory = {
+            command = "npx";
+            args = [
+              "-y"
+              "@modelcontextprotocol/server-memory"
+            ];
+          };
+          time = {
+            command = "uvx";
+            args = [
+              "mcp-server-time"
+              "--local-timezone=America/New_York"
+            ];
+          };
+          mcp_sse = {
+            type = "sse";
+            url = "http://127.0.0.1:8001/sse";
+            headers = {
+              Authorization = "Bearer token";
+              X-Custom-Header = "value";
+            };
+          };
+          mcp_streamable_http = {
+            type = "streamable_http";
+            url = "http://127.0.0.1:8002/mcp";
+          };
+        };
+      };
+    };
+  };
+
+  config = mkIf cfg.enable {
+    systemd.tmpfiles.rules = [
+      "d ${cfg.workDir} - ${cfg.user} ${cfg.group} - -"
+    ];
+
+    users.users."${cfg.user}" = {
+      isSystemUser = true;
+      group = cfg.group;
+    };
+
+    users.groups."${cfg.group}" = { };
+
+    systemd.services.mcpo = {
+      description = "Service for mcpo, an MCP-to-OpenAPI proxy server.";
+      after = [ "network.target" ];
+      wantedBy = [ "multi-user.target" ];
+      serviceConfig = {
+        ExecStart = "${getExe cfg.package} --config ${configFile}";
+        Restart = "on-failure";
+        User = cfg.user;
+        Group = cfg.group;
+        WorkingDirectory = cfg.workDir;
+      };
+    };
+  };
+}