File compression utils.

utils/compress.go

@@ -0,0 +1,33 @@
+package utils
+
+import (
+	"compress/gzip"
+	"io"
+	"os"
+	"os/exec"
+)
+
+// CompressFile compresses file specified by source to .gz & .bz2
+//
+// It uses internal gzip and external bzip2, see:
+// https://code.google.com/p/go/issues/detail?id=4828
+func CompressFile(source *os.File) error {
+	gzPath := source.Name() + ".gz"
+	gzFile, err := os.Create(gzPath)
+	if err != nil {
+		return err
+	}
+	defer gzFile.Close()
+
+	gzWriter := gzip.NewWriter(gzFile)
+	defer gzWriter.Close()
+
+	source.Seek(0, 0)
+	_, err = io.Copy(gzWriter, source)
+	if err != nil {
+		return err
+	}
+
+	cmd := exec.Command("bzip2", source.Name())
+	return cmd.Run()
+}