Add logger command - also migrate from old config to newer config

config-version-main.go

@@ -0,0 +1,64 @@
+/*
+ * Minio Cloud Storage, (C) 2015 Minio, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package main
+
+import (
+	"encoding/json"
+
+	"github.com/minio/cli"
+	"github.com/minio/minio-xl/pkg/probe"
+)
+
+// Print config version.
+var configVersionCmd = cli.Command{
+	Name:   "version",
+	Usage:  "Print config version.",
+	Action: mainConfigVersion,
+	CustomHelpTemplate: `NAME:
+   minio config {{.Name}} - {{.Usage}}
+
+USAGE:
+   minio config {{.Name}}
+
+`,
+}
+
+func mainConfigVersion(ctx *cli.Context) {
+	if ctx.Args().First() == "help" {
+		cli.ShowCommandHelpAndExit(ctx, "version", 1) // last argument is exit code
+	}
+
+	config, err := loadConfigV2()
+	fatalIf(err.Trace(), "Unable to load config", nil)
+
+	// convert interface{} back to its original struct
+	newConf := config
+	type Version struct {
+		Value string `json:"value"`
+	}
+	if globalJSONFlag {
+		tB, e := json.Marshal(
+			struct {
+				Version Version `json:"version"`
+			}{Version: Version{newConf.Version}},
+		)
+		fatalIf(probe.NewError(e), "Unable to construct version string.", nil)
+		Println(string(tB))
+		return
+	}
+	Println(newConf.Version)
+}