advanced scraping usage works

utils/sleep.go

@@ -0,0 +1,23 @@
+// File: utils/sleep.go
+package utils
+
+import (
+    "math/rand"
+    "time"
+)
+
+func init() {
+    // Seed the RNG once when the package is initialized
+    rand.Seed(time.Now().UnixNano())
+}
+
+// SleepWithJitter sleeps for the given base duration plus or minus 25% random jitter.
+// This helps to avoid perfectly uniform request intervals.
+func SleepWithJitter(base time.Duration) {
+    half := base / 2
+    // Random value in [0, half)
+    randOffset := time.Duration(rand.Int63n(int64(half)))
+    // Shift to center jitter around zero: [-half/2, +half/2)
+    delta := randOffset - half/2
+    time.Sleep(base + delta)
+}