more efficient client side gzip compression

weed/operation/compress.go

@@ -16,40 +16,9 @@ import (
  */
 func IsGzippable(ext, mtype string, data []byte) bool {
 
-	// text
-	if strings.HasPrefix(mtype, "text/") {
-		return true
-	}
-
-	// images
-	switch ext {
-	case ".svg", ".bmp":
-		return true
-	}
-	if strings.HasPrefix(mtype, "image/") {
-		return false
-	}
-
-	// by file name extension
-	switch ext {
-	case ".zip", ".rar", ".gz", ".bz2", ".xz":
-		return false
-	case ".pdf", ".txt", ".html", ".htm", ".css", ".js", ".json":
-		return true
-	case ".php", ".java", ".go", ".rb", ".c", ".cpp", ".h", ".hpp":
-		return true
-	case ".png", ".jpg", ".jpeg":
-		return false
-	}
-
-	// by mime type
-	if strings.HasPrefix(mtype, "application/") {
-		if strings.HasSuffix(mtype, "xml") {
-			return true
-		}
-		if strings.HasSuffix(mtype, "script") {
-			return true
-		}
+	shouldBeZipped, iAmSure := IsGzippableFileType(ext, mtype)
+	if iAmSure {
+		return shouldBeZipped
 	}
 
 	isMostlyText := util.IsText(data)
@@ -57,6 +26,50 @@ func IsGzippable(ext, mtype string, data []byte) bool {
 	return isMostlyText
 }
 
+/*
+* Default more not to gzip since gzip can be done on client side.
+ */
+func IsGzippableFileType(ext, mtype string) (shouldBeZipped, iAmSure bool) {
+
+	// text
+	if strings.HasPrefix(mtype, "text/") {
+		return true, true
+	}
+
+	// images
+	switch ext {
+	case ".svg", ".bmp":
+		return true, true
+	}
+	if strings.HasPrefix(mtype, "image/") {
+		return false, true
+	}
+
+	// by file name extension
+	switch ext {
+	case ".zip", ".rar", ".gz", ".bz2", ".xz":
+		return false, true
+	case ".pdf", ".txt", ".html", ".htm", ".css", ".js", ".json":
+		return true, true
+	case ".php", ".java", ".go", ".rb", ".c", ".cpp", ".h", ".hpp":
+		return true, true
+	case ".png", ".jpg", ".jpeg":
+		return false, true
+	}
+
+	// by mime type
+	if strings.HasPrefix(mtype, "application/") {
+		if strings.HasSuffix(mtype, "xml") {
+			return true, true
+		}
+		if strings.HasSuffix(mtype, "script") {
+			return true, true
+		}
+	}
+
+	return false, false
+}
+
 func GzipData(input []byte) ([]byte, error) {
 	buf := new(bytes.Buffer)
 	w, _ := gzip.NewWriterLevel(buf, flate.BestCompression)