Add cache list support

cmd/minikube/cmd/cache_list.go

@@ -0,0 +1,75 @@
+/*
+Copyright 2017 The Kubernetes Authors All rights reserved.
+
+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 cmd
+
+import (
+	"fmt"
+	"os"
+	"text/template"
+
+	"github.com/golang/glog"
+	"github.com/spf13/cobra"
+	cmdConfig "k8s.io/minikube/cmd/minikube/cmd/config"
+	"k8s.io/minikube/pkg/minikube/constants"
+)
+
+const cacheListFormat = "- {{.CacheImageName}}\n"
+
+type CacheListTemplate struct {
+	CacheImageName   string
+}
+
+// listCacheCmd represents the cache list command
+var listCacheCmd = &cobra.Command{
+	Use:   "list",
+	Short: "List all available images from the local cache.",
+	Long:  "List all available images from the local cache.",
+	Run: func(cmd *cobra.Command, args []string) {
+		// list images from config file
+		images, err := cmdConfig.ListConfigMap(constants.Cache)
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "Error listing images: %s\n", err)
+			os.Exit(1)
+		}
+		if err := cacheList(images); err != nil {
+			fmt.Fprintf(os.Stderr, "Error listing images: %s\n", err)
+			os.Exit(1)
+		}
+	},
+}
+
+func init() {
+	cacheCmd.AddCommand(listCacheCmd)
+	RootCmd.AddCommand(cacheCmd)
+}
+
+func cacheList(images map[string]interface{}) error {
+	for imageName := range images {
+		tmpl, err := template.New("list").Parse(cacheListFormat)
+		if err != nil {
+			glog.Errorln("Error creating list template:", err)
+			os.Exit(1)
+		}
+		listTmplt := CacheListTemplate{imageName}
+		err = tmpl.Execute(os.Stdout, listTmplt)
+		if err != nil {
+			glog.Errorln("Error executing list template:", err)
+			os.Exit(1)
+		}
+	}
+	return nil
+}

cmd/minikube/cmd/config/config.go

@@ -219,6 +219,21 @@ func configurableFields() string {
 	return strings.Join(fields, "\n")
 }
 
+// ListConfigMap list entries from config file
+func ListConfigMap(name string) (map[string]interface{}, error) {
+	configFile, err := config.ReadConfig()
+	if err != nil {
+		return nil, err
+	}
+	newImages := make(map[string]interface{})
+	if values, ok := configFile[name].(map[string]interface{}); ok {
+		for key := range values {
+			newImages[key] = nil
+		}
+	}
+	return newImages, nil
+}
+
 // AddToConfigMap adds entries to a map in the config file
 func AddToConfigMap(name string, images []string) error {
 	s, err := findSetting(name)