Added weight/priority balancer tests yyyar#204

test/weight_test.go

@@ -10,6 +10,124 @@ import (
 	"github.com/yyyar/gobetween/core"
 )
 
+func TestOnlyBestPriorityBackendsElected(t *testing.T) {
+	rand.Seed(time.Now().Unix())
+	balancer := &balance.WeightBalancer{}
+	var context core.Context
+
+	context = DummyContext{}
+
+	backends := []*core.Backend{
+		{
+			Priority: 0,
+			Weight:   0,
+		},
+		{
+			Priority: 0,
+			Weight:   1,
+		},
+		{
+			Priority: 0,
+			Weight:   2,
+		},
+		{
+			Priority: 1,
+			Weight:   0,
+		},
+		{
+			Priority: 1,
+			Weight:   1,
+		},
+		{
+			Priority: 1,
+			Weight:   2,
+		},
+		{
+			Priority: 2,
+			Weight:   0,
+		},
+		{
+			Priority: 2,
+			Weight:   1,
+		},
+		{
+			Priority: 2,
+			Weight:   2,
+		},
+	}
+
+	hits := make(map[int]bool)
+
+	for try := 0; try < 100; try++ {
+		backend, err := balancer.Elect(context, backends)
+		if err != nil {
+			t.Fatal(err)
+		}
+
+		hits[backend.Priority] = true
+		if len(hits) > 1 {
+			t.Error("Backends with different priority elected")
+		}
+
+		if backend.Priority != 0 {
+			t.Error("Backends with not optimal priority elected")
+		}
+
+	}
+
+}
+
+func TestAllWeightsEqualTo0Distribution(t *testing.T) {
+	rand.Seed(time.Now().Unix())
+	balancer := &balance.WeightBalancer{}
+	var context core.Context
+
+	context = DummyContext{}
+
+	backends := []*core.Backend{
+		{
+			Target: core.Target{
+				Host: "1",
+				Port: "1",
+			},
+			Weight: 0,
+		},
+		{
+			Target: core.Target{
+				Host: "2",
+				Port: "2",
+			},
+			Weight: 0,
+		},
+		{
+			Target: core.Target{
+				Host: "3",
+				Port: "3",
+			},
+			Weight: 0,
+		},
+	}
+
+	hits := make(map[string]bool)
+
+	for try := 0; try < 100; try++ {
+		backend, err := balancer.Elect(context, backends)
+		if err != nil {
+			t.Fatal(err)
+		}
+
+		hits[backend.Target.Host] = true
+		if len(hits) == 3 {
+			return
+		}
+
+	}
+
+	if len(hits) != 3 {
+		t.Error("Group of backends with weight = 0 has some backneds that are never elected")
+	}
+}
+
 func TestWeightDistribution(t *testing.T) {
 	rand.Seed(time.Now().Unix())
 	balancer := &balance.WeightBalancer{}
@@ -19,16 +137,25 @@ func TestWeightDistribution(t *testing.T) {
 
 	backends := []*core.Backend{
 		{
-			Weight: 20,
+			Priority: 1,
+			Weight:   20,
 		},
 		{
-			Weight: 15,
+			Priority: 1,
+			Weight:   15,
 		},
 		{
-			Weight: 25,
+			Priority: 1,
+			Weight:   25,
 		},
 		{
-			Weight: 40,
+			Priority: 1,
+			Weight:   40,
+		},
+		{
+			// this backend is ignored
+			Priority: 2,
+			Weight:   244,
 		},
 	}
 
@@ -45,6 +172,9 @@ func TestWeightDistribution(t *testing.T) {
 	quantity := make(map[int]int)
 
 	for _, backend := range backends {
+		if backend.Priority > 1 {
+			continue
+		}
 		quantity[backend.Weight] = 0
 	}