improve(search): progress & retries

search/progress.go

@@ -0,0 +1,22 @@
+package search
+
+type writeCounter struct {
+	Total            int64
+	Current          int64
+	ProgressFunction func(float32)
+}
+
+func (wc *writeCounter) Write(p []byte) (int, error) {
+	n := len(p)
+	wc.Current += int64(n)
+	wc.flushProgress()
+	return n, nil
+}
+
+func (wc *writeCounter) flushProgress() {
+	if wc.ProgressFunction == nil || wc.Total < 100000 {
+		return
+	}
+	percentage := float32(wc.Current) * 100 / float32(wc.Total)
+	wc.ProgressFunction(percentage)
+}