Add tar+gzip and tar+zstd compressed archive support.

src/extract.go

@@ -4,11 +4,13 @@ import (
 	"archive/tar"
 	"archive/zip"
 	"bytes"
+	"compress/gzip"
 	"errors"
 	"fmt"
 	"io"
 	"strings"
 
+	"github.com/klauspost/compress/zstd"
 	"google.golang.org/protobuf/proto"
 )
 
@@ -69,6 +71,26 @@ func ExtractTar(reader io.Reader) (*Manifest, error) {
 	return &manifest, nil
 }
 
+func ExtractTarGzip(reader io.Reader) (*Manifest, error) {
+	stream, err := gzip.NewReader(reader)
+	if err != nil {
+		return nil, err
+	}
+	defer stream.Close()
+
+	return ExtractTar(stream)
+}
+
+func ExtractTarZstd(reader io.Reader) (*Manifest, error) {
+	stream, err := zstd.NewReader(reader)
+	if err != nil {
+		return nil, err
+	}
+	defer stream.Close()
+
+	return ExtractTar(stream)
+}
+
 var errZipBomb = errors.New("zip file size limit exceeded")
 
 func ExtractZip(reader io.Reader) (*Manifest, error) {

src/update.go

@@ -114,7 +114,13 @@ func UpdateFromArchive(
 	switch contentType {
 	case "application/x-tar":
 		log.Printf("update %s: (tar)", webRoot)
-		manifest, err = ExtractTar(reader) // yellow? definitely yellow.
+		manifest, err = ExtractTar(reader) // yellow?
+	case "application/x-tar+gzip":
+		log.Printf("update %s: (tar.gz)", webRoot)
+		manifest, err = ExtractTarGzip(reader) // definitely yellow.
+	case "application/x-tar+zstd":
+		log.Printf("update %s: (tar.zst)", webRoot)
+		manifest, err = ExtractTarZstd(reader)
 	case "application/zip":
 		log.Printf("update %s: (zip)", webRoot)
 		manifest, err = ExtractZip(reader)