Figured out it was the filters for XZ that was causing problems

Added lzma and xz decompression.
Renamed Zlib to Gzip

internal/compression/lzma.go

@@ -0,0 +1,25 @@
+package compression
+
+import (
+	"bytes"
+	"io"
+
+	"github.com/ulikunitz/xz/lzma"
+)
+
+//Lzma is a lzma decompressor
+type Lzma struct{}
+
+//Decompress decompresses all the data in the given reader and returns the uncompressed bytes.
+func (l *Lzma) Decompress(rdr io.Reader) ([]byte, error) {
+	r, err := lzma.NewReader(rdr)
+	if err != nil {
+		return nil, err
+	}
+	var buf bytes.Buffer
+	_, err = io.Copy(&buf, r)
+	if err != nil {
+		return nil, err
+	}
+	return buf.Bytes(), nil
+}