cahnges for getting release from release official site

packer/plugin-getter/plugins_test.go

@@ -503,6 +503,42 @@ func (g *mockPluginGetter) Get(what string, options GetOptions) (io.ReadCloser,
 	return io.NopCloser(read), nil
 }
 
+func (g *mockPluginGetter) GetOfficialRelease(what string, options GetOptions) (io.ReadCloser, error) {
+
+	var toEncode interface{}
+	switch what {
+	case "releases":
+		toEncode = g.Releases
+	case "sha256":
+		enc, ok := g.ChecksumFileEntries[options.version.String()]
+		if !ok {
+			return nil, fmt.Errorf("No checksum available for version %q", options.version.String())
+		}
+		toEncode = enc
+	case "zip":
+		// Note: we'll act as if the plugin sources would always be github sources for now.
+		// This test will need to be updated if/when we move on to support other sources.
+		parts := options.PluginRequirement.Identifier.Parts()
+		acc := fmt.Sprintf("%s/%s/packer-plugin-%s/%s", parts[0], parts[1], parts[2], options.ExpectedZipFilename())
+
+		zip, found := g.Zips[acc]
+		if found == false {
+			panic(fmt.Sprintf("could not find zipfile %s. %v", acc, g.Zips))
+		}
+		return zip, nil
+	default:
+		panic("Don't know how to get " + what)
+	}
+
+	read, write := io.Pipe()
+	go func() {
+		if err := json.NewEncoder(write).Encode(toEncode); err != nil {
+			panic(err)
+		}
+	}()
+	return io.NopCloser(read), nil
+}
+
 func zipFile(content map[string]string) io.ReadCloser {
 	buff := bytes.NewBuffer(nil)
 	zipWriter := zip.NewWriter(buff)