azure: move the .vhd extension logic to the callers

It always felt wrong that the method uploaded the blob under a different name
than the one specified in the blob metadata.

This commit moves the responsibility of specifying the right extension to
the callers. azure.EnsureVHDExtension helper was added to simplify this.

Signed-off-by: Ondřej Budai <ondrej@budai.cz>

cmd/osbuild-upload-azure/main.go

@@ -43,10 +43,12 @@ func main() {
 		os.Exit(1)
 	}
 
+	blobName := azure.EnsureVHDExtension(path.Base(fileName))
+
 	err = c.UploadPageBlob(
 		azure.BlobMetadata{
 			StorageAccount: storageAccount,
-			BlobName:       path.Base(fileName),
+			BlobName:       blobName,
 			ContainerName:  containerName,
 		},
 		fileName,

cmd/osbuild-worker/jobimpl-osbuild.go

@@ -527,10 +527,12 @@ func (impl *OSBuildJobImpl) Run(job worker.Job) error {
 				return err
 			}
 
+			// Azure cannot create an image from a blob without .vhd extension
+			blobName := azure.EnsureVHDExtension(args.Targets[0].ImageName)
 			metadata := azure.BlobMetadata{
 				StorageAccount: options.StorageAccount,
 				ContainerName:  options.Container,
-				BlobName:       args.Targets[0].ImageName,
+				BlobName:       blobName,
 			}
 
 			const azureMaxUploadGoroutines = 4
@@ -677,10 +679,8 @@ func (impl *OSBuildJobImpl) Run(job worker.Job) error {
 				return nil
 			}
 
-			blobName := args.Targets[0].ImageName
-			if !strings.HasSuffix(blobName, ".vhd") {
-				blobName += ".vhd"
-			}
+			// Azure cannot create an image from a blob without .vhd extension
+			blobName := azure.EnsureVHDExtension(args.Targets[0].ImageName)
 
 			logWithId.Info("[Azure] ⬆ Uploading the image")
 			err = azureStorageClient.UploadPageBlob(

internal/upload/azure/azurestorage.go

@@ -56,12 +56,10 @@ const DefaultUploadThreads = 16
 // UploadPageBlob takes the metadata and credentials required to upload the image specified by `fileName`
 // It can speed up the upload by using goroutines. The number of parallel goroutines is bounded by
 // the `threads` argument.
+//
+// Note that if you want to create an image out of the page blob, make sure that metadata.BlobName
+// has a .vhd extension, see EnsureVHDExtension.
 func (c StorageClient) UploadPageBlob(metadata BlobMetadata, fileName string, threads int) error {
-	// Azure cannot create an image from a storage blob without .vhd extension
-	if !strings.HasSuffix(metadata.BlobName, ".vhd") {
-		metadata.BlobName = metadata.BlobName + ".vhd"
-	}
-
 	// get storage account blob service URL endpoint.
 	URL, _ := url.Parse(fmt.Sprintf("https://%s.blob.core.windows.net/%s", metadata.StorageAccount, metadata.ContainerName))
 
@@ -205,3 +203,13 @@ func RandomStorageAccountName(prefix string) string {
 
 	return (prefix + id)[:24]
 }
+
+// EnsureVHDExtension returns the given string with .vhd suffix if it already
+// doesn't have one.
+func EnsureVHDExtension(s string) string {
+	if strings.HasSuffix(s, ".vhd") {
+		return s
+	}
+
+	return s + ".vhd"
+}

internal/upload/azure/azurestorage_test.go

@@ -5,6 +5,7 @@ import (
 	"testing"
 
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 )
 
 func TestRandomStorageAccountName(t *testing.T) {
@@ -15,3 +16,18 @@ func TestRandomStorageAccountName(t *testing.T) {
 	r := regexp.MustCompile(`^[\d\w]{24}$`)
 	assert.True(t, r.MatchString(randomName), "the returned name should be 24 characters long and contain only alphanumerical characters")
 }
+
+func TestEnsureVHDExtension(t *testing.T) {
+	tests := []struct {
+		s    string
+		want string
+	}{
+		{s: "toucan.zip", want: "toucan.zip.vhd"},
+		{s: "kingfisher.vhd", want: "kingfisher.vhd"},
+	}
+	for _, tt := range tests {
+		t.Run(tt.s, func(t *testing.T) {
+			require.Equal(t, tt.want, EnsureVHDExtension(tt.s))
+		})
+	}
+}