feat(plugin): Add option to update plugin (#1462)

* Add option to update plugin

- add plugin update [pluginName] to update
- add supporting test

* refactor: wrap errors

pkg/commands/app.go

@@ -686,6 +686,12 @@ func NewPluginCommand() *cli.Command {
 				ArgsUsage: "PLUGIN_NAME [PLUGIN_OPTIONS]",
 				Action:    plugin.Run,
 			},
+			{
+				Name:      "update",
+				Usage:     "update an existing plugin",
+				ArgsUsage: "PLUGIN_NAME",
+				Action:    plugin.Update,
+			},
 		},
 	}
 }

pkg/commands/plugin/plugin.go

@@ -90,6 +90,24 @@ func List(c *cli.Context) error {
 	return nil
 }
 
+// Update updates an existing plugin
+func Update(c *cli.Context) error {
+	if c.NArg() != 1 {
+		cli.ShowSubcommandHelpAndExit(c, 1)
+	}
+
+	if err := initLogger(c); err != nil {
+		return xerrors.Errorf("initialize error: %w", err)
+	}
+
+	pluginName := c.Args().First()
+	if err := plugin.Update(pluginName); err != nil {
+		return xerrors.Errorf("plugin update error: %w", err)
+	}
+
+	return nil
+}
+
 // Run runs the plugin
 func Run(c *cli.Context) error {
 	if c.NArg() < 1 {

pkg/plugin/plugin.go

@@ -10,7 +10,7 @@ import (
 	"strings"
 
 	"golang.org/x/xerrors"
-	yaml "gopkg.in/yaml.v3"
+	"gopkg.in/yaml.v3"
 
 	"github.com/aquasecurity/trivy/pkg/downloader"
 	"github.com/aquasecurity/trivy/pkg/log"
@@ -206,7 +206,6 @@ Plugin: %s
   Description: %s
   Version:     %s
   Usage:       %s
-
 `, plugin.Name, plugin.Description, plugin.Version, plugin.Usage), nil
 }
 
@@ -230,6 +229,35 @@ func List() (string, error) {
 	return strings.Join(pluginList, "\n"), nil
 }
 
+// Update updates an existing plugin
+func Update(name string) error {
+	pluginDir := filepath.Join(dir(), name)
+
+	if _, err := os.Stat(pluginDir); err != nil {
+		if os.IsNotExist(err) {
+			return xerrors.Errorf("could not find a plugin called '%s' to update: %w", name, err)
+		}
+		return err
+	}
+
+	plugin, err := loadMetadata(pluginDir)
+	if err != nil {
+		return err
+	}
+	log.Logger.Infof("Updating plugin '%s'", name)
+	updated, err := Install(nil, plugin.Repository, true)
+	if err != nil {
+		return xerrors.Errorf("unable to perform an update installation: %w", err)
+	}
+
+	if plugin.Version == updated.Version {
+		log.Logger.Infof("The %s plugin is the latest version. [%s]", name, plugin.Version)
+	} else {
+		log.Logger.Infof("Updated '%s' from %s to %s", name, plugin.Version, updated.Version)
+	}
+	return nil
+}
+
 // LoadAll loads all plugins
 func LoadAll() ([]Plugin, error) {
 	pluginsDir := dir()

pkg/plugin/plugin_test.go

@@ -316,7 +316,7 @@ description: A simple test plugin`
 	// Get Information for the plugin
 	info, err := plugin.Information(pluginName)
 	require.NoError(t, err)
-	assert.Equal(t, "\nPlugin: test_plugin\n  Description: A simple test plugin\n  Version:     0.1.0\n  Usage:       test\n\n", info)
+	assert.Equal(t, "\nPlugin: test_plugin\n  Description: A simple test plugin\n  Version:     0.1.0\n  Usage:       test\n", info)
 
 	// Get Information for unknown plugin
 	info, err = plugin.Information("unknown")
@@ -378,3 +378,46 @@ func TestLoadAll1(t *testing.T) {
 		})
 	}
 }
+
+func TestUpdate(t *testing.T) {
+	pluginName := "test_plugin"
+
+	tempDir := t.TempDir()
+	pluginDir := filepath.Join(tempDir, ".trivy", "plugins", pluginName)
+
+	t.Setenv("XDG_DATA_HOME", tempDir)
+
+	// Create the test plugin directory
+	err := os.MkdirAll(pluginDir, os.ModePerm)
+	require.NoError(t, err)
+
+	// write the plugin name
+	pluginMetadata := `name: "test_plugin"
+repository: testdata/test_plugin
+version: "0.0.5"
+usage: test
+description: A simple test plugin`
+
+	err = os.WriteFile(filepath.Join(pluginDir, "plugin.yaml"), []byte(pluginMetadata), os.ModePerm)
+	require.NoError(t, err)
+
+	// verify initial version
+	verifyVersion(t, pluginName, "0.0.5")
+
+	// Update the existing plugin
+	err = plugin.Update(pluginName)
+	require.NoError(t, err)
+
+	// verify plugin updated
+	verifyVersion(t, pluginName, "0.1.0")
+}
+
+func verifyVersion(t *testing.T, pluginName, expectedVersion string) {
+	plugins, err := plugin.LoadAll()
+	require.NoError(t, err)
+	for _, plugin := range plugins {
+		if plugin.Name == pluginName {
+			assert.Equal(t, expectedVersion, plugin.Version)
+		}
+	}
+}