feat: add null:// update handler

internal/data/updater/null/updater_handler.go

@@ -0,0 +1,34 @@
+package null
+
+import (
+	"io"
+	"net/url"
+)
+
+const SchemeNull = "null"
+
+type UpdaterHandler struct{}
+
+func (h *UpdaterHandler) Match(url *url.URL) bool {
+	return url.Scheme == SchemeNull
+}
+
+func (u *UpdaterHandler) Update(url *url.URL) (io.WriteCloser, error) {
+	return &nullCloser{}, nil
+}
+
+func NewUpdaterHandler() *UpdaterHandler {
+	return &UpdaterHandler{}
+}
+
+type nullCloser struct {
+	io.WriteCloser
+}
+
+func (c *nullCloser) Write(p []byte) (n int, err error) {
+	return io.Discard.Write(p)
+}
+
+func (c *nullCloser) Close() error {
+	return nil
+}