WIP: Clsuter support (cross node delivery, leader election)

util/bloom_test.go

@@ -0,0 +1,61 @@
+package util_test
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+	"heckel.io/ntfy/v2/util"
+)
+
+func TestBloomFilter_NoFalseNegatives(t *testing.T) {
+	// The property routing correctness relies on: an added element is ALWAYS reported present
+	b := util.NewBloomFilter(1000, 0.01)
+	for i := 0; i < 1000; i++ {
+		b.Add(fmt.Sprintf("topic-%d", i))
+	}
+	for i := 0; i < 1000; i++ {
+		require.True(t, b.Contains(fmt.Sprintf("topic-%d", i)))
+	}
+}
+
+func TestBloomFilter_FalsePositiveRate(t *testing.T) {
+	b := util.NewBloomFilter(10000, 0.01)
+	for i := 0; i < 10000; i++ {
+		b.Add(fmt.Sprintf("added-%d", i))
+	}
+	falsePositives := 0
+	for i := 0; i < 10000; i++ {
+		if b.Contains(fmt.Sprintf("absent-%d", i)) {
+			falsePositives++
+		}
+	}
+	require.Less(t, falsePositives, 300, "expected ~1%% false positives, got %d/10000", falsePositives)
+}
+
+func TestBloomFilter_EmptyContainsNothing(t *testing.T) {
+	b := util.NewBloomFilter(100, 0.01)
+	require.False(t, b.Contains("anything"))
+}
+
+func TestBloomFilter_MarshalRoundTrip(t *testing.T) {
+	b := util.NewBloomFilter(500, 0.01)
+	for i := 0; i < 500; i++ {
+		b.Add(fmt.Sprintf("topic-%d", i))
+	}
+	data, err := b.MarshalBinary()
+	require.Nil(t, err)
+	b2, err := util.UnmarshalBloomFilter(data)
+	require.Nil(t, err)
+	for i := 0; i < 500; i++ {
+		require.True(t, b2.Contains(fmt.Sprintf("topic-%d", i)))
+	}
+	require.False(t, b2.Contains("never-added-topic"))
+}
+
+func TestBloomFilter_UnmarshalGarbage(t *testing.T) {
+	_, err := util.UnmarshalBloomFilter([]byte{})
+	require.Error(t, err)
+	_, err = util.UnmarshalBloomFilter([]byte{1, 2, 3})
+	require.Error(t, err)
+}