From 2954726ca423469fd493882c9a2d8b727ba1f77d Mon Sep 17 00:00:00 2001
From: Adam Fisk <afisk@getlantern.org>
Date: Fri, 6 Dec 2024 13:24:33 -0700
Subject: [PATCH] Use a random range to avoid quick checks

---
 fronted.go      |  6 +++++-
 fronted_test.go | 22 ++++++++++++++++++++++
 2 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/fronted.go b/fronted.go
index 7cb6ed0..d717eeb 100644
--- a/fronted.go
+++ b/fronted.go
@@ -235,7 +235,7 @@ func (f *fronted) findWorkingFronts() {
 			case <-f.stopCh:
 				log.Debug("findWorkingFronts::Stopping parallel dialing")
 				return
-			case <-time.After(time.Duration(rand.IntN(12000)) * time.Millisecond):
+			case <-time.After(time.Duration(randRange(6, 12)) * time.Second):
 				// Run again after a random time between 0 and 12 seconds
 			}
 		}
@@ -623,3 +623,7 @@ func cloneRequestWith(req *http.Request, frontedHost string, body io.ReadCloser)
 	}
 	return r, nil
 }
+
+func randRange(min, max int) int {
+	return rand.IntN(max-min) + min
+}
diff --git a/fronted_test.go b/fronted_test.go
index e1a5b21..2ac5fb0 100644
--- a/fronted_test.go
+++ b/fronted_test.go
@@ -900,6 +900,28 @@ func TestLoadFronts(t *testing.T) {
 	}
 }
 
+func TestRandRange(t *testing.T) {
+	tests := []struct {
+		min, max int
+	}{
+		{1, 10},
+		{5, 15},
+		{0, 100},
+		{-10, 10},
+		{50, 60},
+	}
+
+	for _, tt := range tests {
+		t.Run(fmt.Sprintf("min=%d,max=%d", tt.min, tt.max), func(t *testing.T) {
+			for i := 0; i < 100; i++ {
+				result := randRange(tt.min, tt.max)
+				assert.GreaterOrEqual(t, result, tt.min)
+				assert.Less(t, result, tt.max)
+			}
+		})
+	}
+}
+
 // Generate a mock of a MasqueradeInterface with a Dial method that can optionally
 // return an error after a specified number of milliseconds.
 func newMockFront(domain string, ipAddress string, timeout time.Duration, passesCheck bool) *mockFront {