Add some unit tests

go/inst/instance_topology_dao.go

@@ -676,10 +676,10 @@ func classifyAndPrioritizeReplicas(replicas []*Instance, includeNonReplicatingIn
 		}
 	}
 
-	// Sort replicas by priority, promotion rule and name
+	// Sort replicas by priority (higher number means higher priority), promotion rule and name
 	sort.Slice(possibleSemiSyncReplicas, func(i, j int) bool {
 		if possibleSemiSyncReplicas[i].SemiSyncPriority != possibleSemiSyncReplicas[j].SemiSyncPriority {
-			return possibleSemiSyncReplicas[i].SemiSyncPriority < possibleSemiSyncReplicas[j].SemiSyncPriority
+			return possibleSemiSyncReplicas[i].SemiSyncPriority > possibleSemiSyncReplicas[j].SemiSyncPriority
 		}
 		if possibleSemiSyncReplicas[i].PromotionRule != possibleSemiSyncReplicas[j].PromotionRule {
 			return possibleSemiSyncReplicas[i].PromotionRule.BetterThan(possibleSemiSyncReplicas[j].PromotionRule)

go/inst/instance_topology_dao_test.go

+package inst
+
+import (
+	"github.com/openark/golib/log"
+	"github.com/openark/orchestrator/go/config"
+	"testing"
+)
+
+func init() {
+	config.Config.HostnameResolveMethod = "none"
+	config.MarkConfigurationLoaded()
+	log.SetLevel(log.ERROR)
+}
+
+func newTestReplica(key string, masterKey string, lastCheckValid bool, downtimed bool, semiSyncPriority uint, promotionRule CandidatePromotionRule, replicationState ReplicationThreadState) *Instance {
+	return &Instance{
+		Key:                       InstanceKey{Hostname: key, Port: 3306},
+		MasterKey:                 InstanceKey{Hostname: masterKey, Port: 3306},
+		ReadBinlogCoordinates:     BinlogCoordinates{LogFile: "mysql.000001", LogPos: 10},
+		ReplicationSQLThreadState: replicationState,
+		ReplicationIOThreadState:  replicationState,
+		IsLastCheckValid:          lastCheckValid,
+		IsDowntimed:               downtimed,
+		SemiSyncPriority:          semiSyncPriority,
+		PromotionRule:             promotionRule,
+	}
+}
+
+func expectInstancesMatch(t *testing.T, actual []*Instance, expected []*Instance) {
+	if len(expected) != len(actual) {
+		t.Fatalf("Actual instance list %+v does not match expected list %+v", actual, expected)
+	}
+	for i := range actual {
+		if actual[i] != expected[i] {
+			t.Fatalf("Actual instance %+v does not match expected %+v", actual[i], expected[i])
+		}
+	}
+}
+
+func TestClassifyAndPrioritizeReplicas_NoPrioritiesSamePromotionRule_NameTiebreaker(t *testing.T) {
+	replica1 := newTestReplica("replica1", "master1", true, false, 1, NeutralPromoteRule, ReplicationThreadStateRunning)
+	replica2 := newTestReplica("replica2", "master1", true, false, 1, NeutralPromoteRule, ReplicationThreadStateRunning)
+	replica3 := newTestReplica("replica3", "master1", true, false, 1, NeutralPromoteRule, ReplicationThreadStateRunning)
+	replicas := []*Instance{replica3, replica2, replica1} // inverse order!
+
+	possibleSemiSyncReplicas, asyncReplicas, excludedReplicas := classifyAndPrioritizeReplicas(replicas, nil)
+	expectInstancesMatch(t, possibleSemiSyncReplicas, []*Instance{replica1, replica2, replica3})
+	expectInstancesMatch(t, asyncReplicas, []*Instance{})
+	expectInstancesMatch(t, excludedReplicas, []*Instance{})
+}
+
+func TestClassifyAndPrioritizeReplicas_WithPriorities(t *testing.T) {
+	replica1 := newTestReplica("replica1", "master1", true, false, 1, NeutralPromoteRule, ReplicationThreadStateRunning)
+	replica2 := newTestReplica("replica2", "master1", true, false, 3, NeutralPromoteRule, ReplicationThreadStateRunning)
+	replica3 := newTestReplica("replica3", "master1", true, false, 2, NeutralPromoteRule, ReplicationThreadStateRunning)
+	replicas := []*Instance{replica1, replica2, replica3}
+
+	possibleSemiSyncReplicas, asyncReplicas, excludedReplicas := classifyAndPrioritizeReplicas(replicas, nil)
+	expectInstancesMatch(t, possibleSemiSyncReplicas, []*Instance{replica2, replica3, replica1})
+	expectInstancesMatch(t, asyncReplicas, []*Instance{})
+	expectInstancesMatch(t, excludedReplicas, []*Instance{})
+}
+
+func TestClassifyAndPrioritizeReplicas_WithPrioritiesAndPromotionRules_PriorityTakesPrecedence(t *testing.T) {
+	replica1 := newTestReplica("replica1", "master1", true, false, 1, PreferPromoteRule, ReplicationThreadStateRunning)
+	replica2 := newTestReplica("replica2", "master1", true, false, 3, MustNotPromoteRule, ReplicationThreadStateRunning)
+	replica3 := newTestReplica("replica3", "master1", true, false, 2, NeutralPromoteRule, ReplicationThreadStateRunning)
+	replicas := []*Instance{replica1, replica2, replica3}
+
+	possibleSemiSyncReplicas, asyncReplicas, excludedReplicas := classifyAndPrioritizeReplicas(replicas, nil)
+	expectInstancesMatch(t, possibleSemiSyncReplicas, []*Instance{replica2, replica3, replica1})
+	expectInstancesMatch(t, asyncReplicas, []*Instance{})
+	expectInstancesMatch(t, excludedReplicas, []*Instance{})
+}
+
+func TestClassifyAndPrioritizeReplicas_LastCheckInvalidAndNotReplication(t *testing.T) {
+	replica1 := newTestReplica("replica1", "master1", true, false, 1, MustNotPromoteRule, ReplicationThreadStateRunning)
+	replica2 := newTestReplica("replica2", "master1", true, false, 1, NeutralPromoteRule, ReplicationThreadStateStopped)
+	replica3 := newTestReplica("replica3", "master1", false, false, 1, PreferPromoteRule, ReplicationThreadStateRunning)
+	replicas := []*Instance{replica1, replica2, replica3}
+
+	possibleSemiSyncReplicas, asyncReplicas, excludedReplicas := classifyAndPrioritizeReplicas(replicas, nil)
+	expectInstancesMatch(t, possibleSemiSyncReplicas, []*Instance{replica1})
+	expectInstancesMatch(t, asyncReplicas, []*Instance{})
+	expectInstancesMatch(t, excludedReplicas, []*Instance{replica2, replica3})
+}
+
+func TestClassifyAndPrioritizeReplicas_Downtimed(t *testing.T) {
+	replica1 := newTestReplica("replica1", "master1", true, false, 1, NeutralPromoteRule, ReplicationThreadStateRunning)
+	replica2 := newTestReplica("replica2", "master1", true, false, 1, NeutralPromoteRule, ReplicationThreadStateRunning)
+	replica3 := newTestReplica("replica3", "master1", true, true, 1, MustNotPromoteRule, ReplicationThreadStateRunning)
+	replica4 := newTestReplica("replica4", "master1", true, false, 0, MustNotPromoteRule, ReplicationThreadStateRunning)
+	replicas := []*Instance{replica1, replica2, replica3, replica4}
+
+	possibleSemiSyncReplicas, asyncReplicas, excludedReplicas := classifyAndPrioritizeReplicas(replicas, nil)
+	expectInstancesMatch(t, possibleSemiSyncReplicas, []*Instance{replica1, replica2})
+	expectInstancesMatch(t, asyncReplicas, []*Instance{replica3, replica4})
+	expectInstancesMatch(t, excludedReplicas, []*Instance{})
+}
+
+func TestClassifyAndPrioritizeReplicas_NonReplicatingReplica(t *testing.T) {
+	replica1 := newTestReplica("replica1", "master1", true, false, 1, NeutralPromoteRule, ReplicationThreadStateRunning)
+	replica2 := newTestReplica("replica2", "master1", true, false, 1, NeutralPromoteRule, ReplicationThreadStateRunning)
+	replica3 := newTestReplica("replica3", "master1", true, false, 1, MustNotPromoteRule, ReplicationThreadStateStopped)
+	replicas := []*Instance{replica1, replica2, replica3}
+
+	possibleSemiSyncReplicas, asyncReplicas, excludedReplicas := classifyAndPrioritizeReplicas(replicas, &replica3.Key) // Non-replicating instance
+	expectInstancesMatch(t, possibleSemiSyncReplicas, []*Instance{replica1, replica2, replica3})
+	expectInstancesMatch(t, asyncReplicas, []*Instance{})
+	expectInstancesMatch(t, excludedReplicas, []*Instance{})
+}