lang: funcs: core: os: Add an args function to read argv

examples/lang/args.mcl

@@ -0,0 +1,7 @@
+import "fmt"
+import "os"
+
+# show the argv of this process
+print "print" {
+	msg => fmt.printf("args(%d): %v", len(os.args()), os.args()),
+}

lang/funcs/core/os/args_func.go

@@ -0,0 +1,47 @@
+// Mgmt
+// Copyright (C) 2013-2024+ James Shubin and the project contributors
+// Written by James Shubin <james@shubin.ca> and the project contributors
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+package coreos
+
+import (
+	"os"
+
+	"github.com/purpleidea/mgmt/lang/funcs/simple"
+	"github.com/purpleidea/mgmt/lang/types"
+)
+
+func init() {
+	simple.ModuleRegister(ModuleName, "args", &types.FuncValue{
+		T: types.NewType("func() []str"),
+		V: Args,
+	})
+}
+
+// Args returns the `argv` of the current process. Keep in mind that this will
+// return different values depending on how this is deployed, so don't expect a
+// result on your deploy client to behave the same as a server receiving code.
+// FIXME: Sanitize any command-line secrets we might pass in by cli.
+func Args([]types.Value) (types.Value, error) {
+	values := []types.Value{}
+	for _, s := range os.Args {
+		values = append(values, &types.StrValue{V: s})
+	}
+	return &types.ListValue{
+		V: values,
+		T: types.NewType("[]str"),
+	}, nil
+}