lib, lang, engine: local: Add Value mechanisms to local API

This expands the Local API with the first (and in theory, only ever) API
for reading and writing simple values. This is a coordination point for
resources and functions to share things directly.

engine/local/local_test.go

@@ -0,0 +1,50 @@
+// Mgmt
+// Copyright (C) 2013-2023+ 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/>.
+
+//go:build !root
+
+package local
+
+import (
+	"context"
+	"fmt"
+	"reflect"
+	"testing"
+)
+
+func TestWrite(t *testing.T) {
+	tmpdir := fmt.Sprintf("%s/", t.TempDir()) // gets cleaned up at end, new dir for each call
+	key := "test1"
+	value := 42
+	if err := valueWrite(context.Background(), tmpdir, key, value); err != nil {
+		t.Errorf("error: %+v", err)
+		return
+	}
+
+	if val, err := valueRead(context.Background(), tmpdir, key); err != nil {
+		t.Errorf("error: %+v", err)
+		return
+	} else if !reflect.DeepEqual(value, val) {
+		t.Errorf("error: not equal: %+v != %+v", val, value)
+		//return
+	}
+
+	if err := valueRemove(context.Background(), tmpdir, key); err != nil {
+		t.Errorf("error: %+v", err)
+		//return
+	}
+}