plugins: Create plugins files only if webui is enabled. Fixes #4592. May fix #4600.

fs/rc/rcserver/rcserver.go

@@ -387,9 +387,10 @@ func (s *Server) handleGet(w http.ResponseWriter, r *http.Request, path string)
 		s.serveRoot(w, r)
 		return
 	case s.files != nil:
+		if s.opt.WebUI {
 			pluginsMatchResult := webgui.PluginsMatch.FindStringSubmatch(path)
 
-		if s.opt.WebUI && pluginsMatchResult != nil && len(pluginsMatchResult) > 2 {
+			if pluginsMatchResult != nil && len(pluginsMatchResult) > 2 {
 				ok := webgui.ServePluginOK(w, r, pluginsMatchResult)
 				if !ok {
 					r.URL.Path = fmt.Sprintf("/%s/%s/app/build/%s", pluginsMatchResult[1], pluginsMatchResult[2], pluginsMatchResult[3])
@@ -397,9 +398,10 @@ func (s *Server) handleGet(w http.ResponseWriter, r *http.Request, path string)
 					return
 				}
 				return
-		} else if s.opt.WebUI && webgui.ServePluginWithReferrerOK(w, r, path) {
+			} else if webgui.ServePluginWithReferrerOK(w, r, path) {
 				return
 			}
+		}
 		// Serve the files
 		r.URL.Path = "/" + path
 		s.files.ServeHTTP(w, r)

fs/rc/webgui/plugins.go

@@ -15,6 +15,8 @@ import (
 
 	"github.com/rclone/rclone/fs"
 	"github.com/rclone/rclone/fs/config"
+	"github.com/rclone/rclone/fs/rc/rcflags"
+	"github.com/rclone/rclone/lib/errors"
 )
 
 // PackageJSON is the structure of package.json of a plugin
@@ -62,6 +64,8 @@ var (
 	PluginsPath              string
 	pluginsConfigPath        string
 	availablePluginsJSONPath = "availablePlugins.json"
+	initSuccess              = false
+	initMutex                = &sync.Mutex{}
 )
 
 func init() {
@@ -69,11 +73,6 @@ func init() {
 	PluginsPath = filepath.Join(cachePath, "plugins")
 	pluginsConfigPath = filepath.Join(PluginsPath, "config")
 
-	loadedPlugins = newPlugins(availablePluginsJSONPath)
-	err := loadedPlugins.readFromFile()
-	if err != nil {
-		fs.Errorf(nil, "error reading available plugins: %v", err)
-	}
 }
 
 // Plugins represents the structure how plugins are saved onto disk
@@ -90,9 +89,25 @@ func newPlugins(fileName string) *Plugins {
 	return &p
 }
 
+func initPluginsOrError() error {
+	if !rcflags.Opt.WebUI {
+		return errors.New("WebUI needs to be enabled for plugins to work")
+	}
+	initMutex.Lock()
+	defer initMutex.Unlock()
+	if !initSuccess {
+		loadedPlugins = newPlugins(availablePluginsJSONPath)
+		err := loadedPlugins.readFromFile()
+		if err != nil {
+			fs.Errorf(nil, "error reading available plugins: %v", err)
+		}
+		initSuccess = true
+	}
+
+	return nil
+}
+
 func (p *Plugins) readFromFile() (err error) {
-	//p.mutex.Lock()
-	//defer p.mutex.Unlock()
 	err = CreatePathIfNotExist(pluginsConfigPath)
 	if err != nil {
 		return err
@@ -169,8 +184,6 @@ func (p *Plugins) addTestPlugin(pluginName string, testURL string, handlesType [
 }
 
 func (p *Plugins) writeToFile() (err error) {
-	//p.mutex.Lock()
-	//defer p.mutex.Unlock()
 	availablePluginsJSON := filepath.Join(pluginsConfigPath, p.fileName)
 
 	file, err := json.MarshalIndent(p, "", " ")
@@ -290,6 +303,10 @@ var referrerPathReg = regexp.MustCompile("^(https?):\\/\\/(.+):([0-9]+)?\\/(.*)\
 // sends a redirect to actual url. This function is useful for plugins to refer to absolute paths when
 // the referrer in http.Request is set
 func ServePluginWithReferrerOK(w http.ResponseWriter, r *http.Request, path string) (ok bool) {
+	err := initPluginsOrError()
+	if err != nil {
+		return false
+	}
 	referrer := r.Referer()
 	referrerPathMatch := referrerPathReg.FindStringSubmatch(referrer)
 

fs/rc/webgui/rc.go

@@ -30,6 +30,10 @@ Eg
 }
 
 func rcListTestPlugins(_ context.Context, _ rc.Params) (out rc.Params, err error) {
+	err = initPluginsOrError()
+	if err != nil {
+		return nil, err
+	}
 	return rc.Params{
 		"loadedTestPlugins": filterPlugins(loadedPlugins, func(json *PackageJSON) bool { return json.isTesting() }),
 	}, nil
@@ -54,6 +58,10 @@ Eg
 	})
 }
 func rcRemoveTestPlugin(_ context.Context, in rc.Params) (out rc.Params, err error) {
+	err = initPluginsOrError()
+	if err != nil {
+		return nil, err
+	}
 	name, err := in.GetString("name")
 	if err != nil {
 		return nil, err
@@ -85,6 +93,10 @@ Eg
 }
 
 func rcAddPlugin(_ context.Context, in rc.Params) (out rc.Params, err error) {
+	err = initPluginsOrError()
+	if err != nil {
+		return nil, err
+	}
 	pluginURL, err := in.GetString("url")
 	if err != nil {
 		return nil, err
@@ -192,6 +204,10 @@ Eg
 }
 
 func rcGetPlugins(_ context.Context, _ rc.Params) (out rc.Params, err error) {
+	err = initPluginsOrError()
+	if err != nil {
+		return nil, err
+	}
 	err = loadedPlugins.readFromFile()
 	if err != nil {
 		return nil, err
@@ -222,6 +238,10 @@ Eg
 }
 
 func rcRemovePlugin(_ context.Context, in rc.Params) (out rc.Params, err error) {
+	err = initPluginsOrError()
+	if err != nil {
+		return nil, err
+	}
 	name, err := in.GetString("name")
 	if err != nil {
 		return nil, err
@@ -260,6 +280,10 @@ Eg
 }
 
 func rcGetPluginsForType(_ context.Context, in rc.Params) (out rc.Params, err error) {
+	err = initPluginsOrError()
+	if err != nil {
+		return nil, err
+	}
 	handlesType, err := in.GetString("type")
 	if err != nil {
 		handlesType = ""

fs/rc/webgui/rc_test.go

@@ -9,6 +9,7 @@ import (
 	"testing"
 
 	"github.com/rclone/rclone/fs/rc"
+	"github.com/rclone/rclone/fs/rc/rcflags"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 )
@@ -18,6 +19,10 @@ const testPluginAuthor = "rclone"
 const testPluginKey = testPluginAuthor + "/" + testPluginName
 const testPluginURL = "https://github.com/" + testPluginAuthor + "/" + testPluginName + "/"
 
+func init() {
+	rcflags.Opt.WebUI = true
+}
+
 func setCacheDir(t *testing.T) string {
 	cacheDir, err := ioutil.TempDir("", "rclone-cache-dir")
 	assert.Nil(t, err)