Plugins: Fix loading of dist folders (#80015)

* end to end

* tidy

* fix whitespace

* remove unused code

* fix linter

* fix gosec + add sort

* fix test

* apply cr feedback

pkg/plugins/manager/sources/sources.go

@@ -2,34 +2,77 @@ package sources
 
 import (
 	"context"
+	"os"
 	"path/filepath"
+	"slices"
 
 	"github.com/grafana/grafana/pkg/plugins"
-	"github.com/grafana/grafana/pkg/plugins/config"
 	"github.com/grafana/grafana/pkg/plugins/log"
 	"github.com/grafana/grafana/pkg/setting"
 )
 
 type Service struct {
-	gCfg *setting.Cfg
-	cfg  *config.Cfg
-	log  log.Logger
+	cfg *setting.Cfg
+	log log.Logger
 }
 
-func ProvideService(gCfg *setting.Cfg, cfg *config.Cfg) *Service {
+func ProvideService(cfg *setting.Cfg) *Service {
 	return &Service{
-		gCfg: gCfg,
-		cfg:  cfg,
-		log:  log.New("plugin.sources"),
+		cfg: cfg,
+		log: log.New("plugin.sources"),
 	}
 }
 
 func (s *Service) List(_ context.Context) []plugins.PluginSource {
-	return []plugins.PluginSource{
-		NewLocalSource(plugins.ClassCore, corePluginPaths(s.gCfg.StaticRootPath)),
-		NewLocalSource(plugins.ClassBundled, []string{s.gCfg.BundledPluginsPath}),
-		NewLocalSource(plugins.ClassExternal, append([]string{s.cfg.PluginsPath}, pluginFSPaths(s.cfg.PluginSettings)...)),
+	r := []plugins.PluginSource{
+		NewLocalSource(plugins.ClassCore, corePluginPaths(s.cfg.StaticRootPath)),
+		NewLocalSource(plugins.ClassBundled, []string{s.cfg.BundledPluginsPath}),
 	}
+	r = append(r, s.externalPluginSources()...)
+	r = append(r, s.pluginSettingSources()...)
+	return r
+}
+
+func (s *Service) externalPluginSources() []plugins.PluginSource {
+	var sources []plugins.PluginSource
+	if s.cfg.PluginsPath == "" {
+		return sources
+	}
+
+	pluginsPath := s.cfg.PluginsPath
+	// It's safe to ignore gosec warning G304 since the variable part of the file path comes from a configuration
+	// variable.
+	// nolint:gosec
+	d, err := os.ReadDir(pluginsPath)
+	if err != nil {
+		s.log.Error("Failed to open plugins path", "path", pluginsPath, "error", err)
+		return sources
+	}
+
+	var pluginDirs []string
+	for _, dir := range d {
+		if dir.IsDir() {
+			pluginDirs = append(pluginDirs, filepath.Join(pluginsPath, dir.Name()))
+		}
+	}
+	slices.Sort(pluginDirs)
+
+	for _, dir := range pluginDirs {
+		sources = append(sources, NewLocalSource(plugins.ClassExternal, []string{dir}))
+	}
+	return sources
+}
+
+func (s *Service) pluginSettingSources() []plugins.PluginSource {
+	var sources []plugins.PluginSource
+	for _, ps := range s.cfg.PluginSettings {
+		path, exists := ps["path"]
+		if !exists || path == "" {
+			continue
+		}
+		sources = append(sources, NewLocalSource(plugins.ClassExternal, []string{path}))
+	}
+	return sources
 }
 
 // corePluginPaths provides a list of the Core plugin file system paths
@@ -38,16 +81,3 @@ func corePluginPaths(staticRootPath string) []string {
 	panelsPath := filepath.Join(staticRootPath, "app/plugins/panel")
 	return []string{datasourcePaths, panelsPath}
 }
-
-// pluginSettingPaths provides plugin file system paths defined in cfg.PluginSettings
-func pluginFSPaths(ps map[string]map[string]string) []string {
-	var pluginSettingDirs []string
-	for _, s := range ps {
-		path, exists := s["path"]
-		if !exists || path == "" {
-			continue
-		}
-		pluginSettingDirs = append(pluginSettingDirs, path)
-	}
-	return pluginSettingDirs
-}