Add gurobi client module

Not yet tested, no license yet

Signed-off-by: Shea Levy <shea@shealevy.com>

nixos/modules/module-list.nix

@@ -47,6 +47,7 @@
   ./programs/bash/command-not-found.nix
   ./programs/blcr.nix
   ./programs/environment.nix
+  ./programs/gurobi.nix
   ./programs/info.nix
   ./programs/shadow.nix
   ./programs/shell.nix

nixos/modules/programs/gurobi.nix

@@ -0,0 +1,41 @@
+{ config, pkgs, ... }:
+
+with pkgs.lib;
+
+let
+  cfg = config.programs.gurobi;
+in {
+  options = {
+    programs.gurobi = {
+      license = mkOption {
+        default = null;
+
+        description = "Path to the Gurobi license file if not using a token server";
+
+        type = types.nullOr types.path;
+      };
+
+      tokenServerAddress = mkOption {
+        default = null;
+
+        description = "Address of the token server";
+
+        type = types.nullOr types.string;
+      };
+    };
+
+    config = mkIf (cfg.license != null || cfg.tokenServerAddress != null) {
+      assertions = [ {
+        assertion = cfg.license == null || cfg.tokenServerAddress == null;
+        message = "Please only set one of a gurobi license file and a gurobi token server address";
+      } ];
+
+      environment.variables.GRB_LICENSE_FILE = if cfg.license != null
+        then cfg.license
+        else pkgs.writeTextFile {
+          name = "gurobi-generated-license";
+          text = "TOKENSERVER=${cfg.tokenServerAddress}";
+        };
+    };
+  };
+}