Plugins: Add file store abstraction for handling plugin files (#65432)

* add file store

* fix markdown fetch bug

* add markdown tests

* fix var name

pkg/services/plugindashboards/service/service.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 
 	"github.com/grafana/grafana/pkg/components/simplejson"
+
 	"github.com/grafana/grafana/pkg/infra/log"
 	pluginDashboardsManager "github.com/grafana/grafana/pkg/plugins/manager/dashboards"
 	"github.com/grafana/grafana/pkg/services/dashboards"
@@ -115,13 +116,7 @@ func (s Service) LoadPluginDashboard(ctx context.Context, req *plugindashboards.
 		return nil, err
 	}
 
-	defer func() {
-		if err = resp.Content.Close(); err != nil {
-			s.logger.Warn("Failed to close plugin dashboard file", "reference", req.Reference, "err", err)
-		}
-	}()
-
-	data, err := simplejson.NewFromReader(resp.Content)
+	data, err := simplejson.NewJson(resp.Content)
 	if err != nil {
 		return nil, err
 	}

pkg/services/plugindashboards/service/service_test.go

@@ -1,10 +1,8 @@
 package service
 
 import (
-	"bytes"
 	"context"
 	"fmt"
-	"io"
 	"sort"
 	"testing"
 
@@ -193,7 +191,7 @@ func (m pluginDashboardStoreMock) GetPluginDashboardFileContents(ctx context.Con
 	if dashboardFiles, exists := m.pluginDashboardFiles[args.PluginID]; exists {
 		if content, exists := dashboardFiles[args.FileReference]; exists {
 			return &dashboards.GetPluginDashboardFileContentsResult{
-				Content: io.NopCloser(bytes.NewReader(content)),
+				Content: content,
 			}, nil
 		}
 	} else if !exists {

pkg/services/pluginsintegration/pluginsintegration.go

@@ -10,6 +10,7 @@ import (
 	"github.com/grafana/grafana/pkg/plugins/config"
 	"github.com/grafana/grafana/pkg/plugins/manager"
 	"github.com/grafana/grafana/pkg/plugins/manager/client"
+	"github.com/grafana/grafana/pkg/plugins/manager/filestore"
 	"github.com/grafana/grafana/pkg/plugins/manager/loader"
 	"github.com/grafana/grafana/pkg/plugins/manager/loader/assetpath"
 	"github.com/grafana/grafana/pkg/plugins/manager/loader/finder"
@@ -60,6 +61,8 @@ var WireSet = wire.NewSet(
 	sources.ProvideService,
 	pluginSettings.ProvideService,
 	wire.Bind(new(pluginsettings.Service), new(*pluginSettings.Service)),
+	filestore.ProvideService,
+	wire.Bind(new(plugins.FileStore), new(*filestore.Service)),
 )
 
 // WireExtensionSet provides a wire.ProviderSet of plugin providers that can be