Fixed some error messages/warnings during index download (#2257)

* Added FAILED_INSTANCE_INIT_REASON_INDEX_DOWNLOAD_ERROR in gRPC Init errors

* Improved error reporting during Init and first-index-update

arduino/cores/packagemanager/package_manager.go

@@ -26,6 +26,7 @@ import (
 	"sync"
 	"time"
 
+	"github.com/arduino/arduino-cli/arduino"
 	"github.com/arduino/arduino-cli/arduino/cores"
 	"github.com/arduino/arduino-cli/arduino/cores/packageindex"
 	"github.com/arduino/arduino-cli/arduino/discovery/discoverymanager"
@@ -34,6 +35,7 @@ import (
 	paths "github.com/arduino/go-paths-helper"
 	properties "github.com/arduino/go-properties-orderedmap"
 	"github.com/arduino/go-timeutils"
+	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
 	semver "go.bug.st/relaxed-semver"
 )
@@ -438,6 +440,9 @@ func (pme *Explorer) determineReferencedPlatformRelease(boardBuildProperties *pr
 // LoadPackageIndex loads a package index by looking up the local cached file from the specified URL
 func (pmb *Builder) LoadPackageIndex(URL *url.URL) error {
 	indexFileName := path.Base(URL.Path)
+	if indexFileName == "." || indexFileName == "" {
+		return &arduino.InvalidURLError{Cause: errors.New(URL.String())}
+	}
 	if strings.HasSuffix(indexFileName, ".tar.bz2") {
 		indexFileName = strings.TrimSuffix(indexFileName, ".tar.bz2") + ".json"
 	}

arduino/resources/index.go

@@ -38,12 +38,15 @@ type IndexResource struct {
 }
 
 // IndexFileName returns the index file name as it is saved in data dir (package_xxx_index.json).
-func (res *IndexResource) IndexFileName() string {
+func (res *IndexResource) IndexFileName() (string, error) {
 	filename := path.Base(res.URL.Path) // == package_index.json[.gz] || packacge_index.tar.bz2
+	if filename == "." || filename == "" {
+		return "", &arduino.InvalidURLError{}
+	}
 	if i := strings.Index(filename, "."); i != -1 {
 		filename = filename[:i]
 	}
-	return filename + ".json"
+	return filename + ".json", nil
 }
 
 // Download will download the index and possibly check the signature using the Arduino's public key.
@@ -63,7 +66,10 @@ func (res *IndexResource) Download(destDir *paths.Path, downloadCB rpc.DownloadP
 
 	// Download index file
 	downloadFileName := path.Base(res.URL.Path) // == package_index.json[.gz] || package_index.tar.bz2
-	indexFileName := res.IndexFileName()        // == package_index.json
+	indexFileName, err := res.IndexFileName()   // == package_index.json
+	if err != nil {
+		return err
+	}
 	tmpIndexPath := tmp.Join(downloadFileName)
 	if err := httpclient.DownloadFile(tmpIndexPath, res.URL.String(), "", tr("Downloading index: %s", downloadFileName), downloadCB, nil, downloader.NoResume); err != nil {
 		return &arduino.FailedDownloadError{Message: tr("Error downloading index '%s'", res.URL), Cause: err}

commands/instances.go

@@ -280,7 +280,14 @@ func Init(req *rpc.InitRequest, responseCallback func(r *rpc.InitResponse)) erro
 			allPackageIndexUrls = append(allPackageIndexUrls, URL)
 		}
 	}
-	firstUpdate(context.Background(), req.GetInstance(), downloadCallback, allPackageIndexUrls)
+	if err := firstUpdate(context.Background(), req.GetInstance(), downloadCallback, allPackageIndexUrls); err != nil {
+		e := &arduino.InitFailedError{
+			Code:   codes.InvalidArgument,
+			Cause:  err,
+			Reason: rpc.FailedInstanceInitReason_FAILED_INSTANCE_INIT_REASON_INDEX_DOWNLOAD_ERROR,
+		}
+		responseError(e.ToRPCStatus())
+	}
 
 	{
 		// We need to rebuild the PackageManager currently in use by this instance
@@ -589,7 +596,12 @@ func firstUpdate(ctx context.Context, instance *rpc.Instance, downloadCb func(ms
 		if URL.Scheme == "file" {
 			continue
 		}
-		packageIndexFileName := (&resources.IndexResource{URL: URL}).IndexFileName()
+		packageIndexFileName, err := (&resources.IndexResource{URL: URL}).IndexFileName()
+		if err != nil {
+			return &arduino.FailedDownloadError{
+				Message: tr("Error downloading index '%s'", URL),
+				Cause:   &arduino.InvalidURLError{}}
+		}
 		packageIndexFile := dataDir.Join(packageIndexFileName)
 		if packageIndexFile.NotExist() {
 			// The index file doesn't exists, that means the CLI is run for the first time,

rpc/cc/arduino/cli/commands/v1/commands.proto

@@ -223,6 +223,9 @@ enum FailedInstanceInitReason {
   // FAILED_INSTANCE_INIT_REASON_TOOL_LOAD_ERROR failure encountered while
   // loading a tool
   FAILED_INSTANCE_INIT_REASON_TOOL_LOAD_ERROR = 3;
+  // FAILED_INSTANCE_INIT_REASON_INDEX_DOWNLOAD_ERROR failure encountered while
+  // downloading an index
+  FAILED_INSTANCE_INIT_REASON_INDEX_DOWNLOAD_ERROR = 4;
 }
 
 message FailedInstanceInitError {