Fix binary data handling, type safety, and Sentry flood protection

- Pass []byte directly in bytesArgsToInterfaces instead of converting to string
- Handle []byte type assertion in argsToBytes for correct Sentry reporting
- Fix responseEqual panic when comparing mismatched interface types
- Return false in ShouldReport when at capacity to prevent Sentry flooding

Author: bootjp

proxy/compare.go

@@ -133,17 +133,18 @@ func isConsistent(primaryResp, secondaryResp interface{}, primaryErr, secondaryE
 
 // responseEqual compares two go-redis response values for equality.
 func responseEqual(a, b interface{}) bool {
-	if a == nil && b == nil {
-		return true
-	}
 	if a == nil || b == nil {
-		return false
-	}
-	switch a := a.(type) {
-	case string, int64:
-		return a == b
+		return a == nil && b == nil
+	}
+	switch av := a.(type) {
+	case string:
+		bv, ok := b.(string)
+		return ok && av == bv
+	case int64:
+		bv, ok := b.(int64)
+		return ok && av == bv
 	case []interface{}:
-		return interfaceSliceEqual(a, b)
+		return interfaceSliceEqual(av, b)
 	default:
 		return reflect.DeepEqual(a, b)
 	}
@@ -208,7 +209,7 @@ func extractKey(args [][]byte) string {
 func bytesArgsToInterfaces(args [][]byte) []interface{} {
 	out := make([]interface{}, len(args))
 	for i, a := range args {
-		out[i] = string(a)
+		out[i] = a
 	}
 	return out
 }

proxy/dualwrite.go

@@ -262,7 +262,11 @@ func (d *DualWriter) Secondary() Backend {
 func argsToBytes(iArgs []interface{}) [][]byte {
 	out := make([][]byte, len(iArgs))
 	for i, a := range iArgs {
-		out[i] = []byte(fmt.Sprintf("%v", a))
+		if b, ok := a.([]byte); ok {
+			out[i] = b
+		} else {
+			out[i] = []byte(fmt.Sprintf("%v", a))
+		}
 	}
 	return out
 }

proxy/proxy_test.go

@@ -196,9 +196,9 @@ func TestBytesArgsToInterfaces(t *testing.T) {
 	args := [][]byte{[]byte("SET"), []byte("key"), []byte("val")}
 	result := bytesArgsToInterfaces(args)
 	assert.Len(t, result, 3)
-	assert.Equal(t, "SET", result[0])
-	assert.Equal(t, "key", result[1])
-	assert.Equal(t, "val", result[2])
+	assert.Equal(t, []byte("SET"), result[0])
+	assert.Equal(t, []byte("key"), result[1])
+	assert.Equal(t, []byte("val"), result[2])
 }
 
 func TestResponseEqual(t *testing.T) {

proxy/sentry.go

@@ -103,9 +103,9 @@ func (r *SentryReporter) ShouldReport(fingerprint string) bool {
 				delete(r.lastReport, k)
 			}
 		}
-		// If still at capacity after eviction, skip tracking to prevent unbounded growth.
+		// If still at capacity after eviction, drop report to prevent unbounded growth and Sentry flooding.
 		if len(r.lastReport) >= maxReportEntries {
-			return true
+			return false
 		}
 	}