subnet/*: Remove unused reservations code

The concept of a reservation was added a long time ago but never exposed
to users. This commit removes that code.

Reservations were part of the subnet manager interface but only
implemented by the etcd backend. The Kube backend had stub code to
implement the interface but threw errors when called.

subnet/etcdv2/local_manager.go

@@ -377,130 +377,6 @@ func isSubnetConfigCompat(config *Config, sn ip.IP4Net) bool {
 	return sn.PrefixLen == config.SubnetLen
 }
 
-func (m *LocalManager) tryAddReservation(ctx context.Context, r *Reservation) error {
-	attrs := &LeaseAttrs{
-		PublicIP: r.PublicIP,
-	}
-
-	_, err := m.registry.createSubnet(ctx, r.Subnet, attrs, 0)
-	switch {
-	case err == nil:
-		return nil
-
-	case !isErrEtcdNodeExist(err):
-		return err
-	}
-
-	// This subnet or its reservation already exists.
-	// Get what's there and
-	// - if PublicIP matches, remove the TTL make it a reservation
-	// - otherwise, error out
-	sub, asof, err := m.registry.getSubnet(ctx, r.Subnet)
-	switch {
-	case err == nil:
-	case isErrEtcdKeyNotFound(err):
-		// Subnet just got expired or was deleted
-		return errTryAgain
-	default:
-		return err
-	}
-
-	if sub.Attrs.PublicIP != r.PublicIP {
-		// Subnet already taken
-		return ErrLeaseTaken
-	}
-
-	// remove TTL
-	_, err = m.registry.updateSubnet(ctx, r.Subnet, &sub.Attrs, 0, asof)
-	if isErrEtcdTestFailed(err) {
-		return errTryAgain
-	}
-	return err
-}
-
-func (m *LocalManager) AddReservation(ctx context.Context, r *Reservation) error {
-	config, err := m.GetNetworkConfig(ctx)
-	if err != nil {
-		return err
-	}
-
-	if config.SubnetLen != r.Subnet.PrefixLen {
-		return fmt.Errorf("reservation subnet has mask incompatible with network config")
-	}
-
-	if !config.Network.Overlaps(r.Subnet) {
-		return fmt.Errorf("reservation subnet is outside of flannel network")
-	}
-
-	for i := 0; i < raceRetries; i++ {
-		err := m.tryAddReservation(ctx, r)
-		switch {
-		case err == nil:
-			return nil
-		case err == errTryAgain:
-			continue
-		default:
-			return err
-		}
-	}
-
-	return ErrNoMoreTries
-}
-
-func (m *LocalManager) tryRemoveReservation(ctx context.Context, subnet ip.IP4Net) error {
-	sub, asof, err := m.registry.getSubnet(ctx, subnet)
-	if err != nil {
-		return err
-	}
-
-	// add back the TTL
-	_, err = m.registry.updateSubnet(ctx, subnet, &sub.Attrs, subnetTTL, asof)
-	if isErrEtcdTestFailed(err) {
-		return errTryAgain
-	}
-	return err
-}
-
-//RemoveReservation removes the subnet by setting TTL back to subnetTTL (24hours)
-func (m *LocalManager) RemoveReservation(ctx context.Context, subnet ip.IP4Net) error {
-	for i := 0; i < raceRetries; i++ {
-		err := m.tryRemoveReservation(ctx, subnet)
-		switch {
-		case err == nil:
-			return nil
-		case err == errTryAgain:
-			continue
-		default:
-			return err
-		}
-	}
-
-	return ErrNoMoreTries
-}
-
-func (m *LocalManager) ListReservations(ctx context.Context) ([]Reservation, error) {
-	subnets, _, err := m.registry.getSubnets(ctx)
-	if err != nil {
-		return nil, err
-	}
-
-	rsvs := []Reservation{}
-	for _, sub := range subnets {
-		// Reservations don't have TTL and so no expiration
-		if !sub.Expiration.IsZero() {
-			continue
-		}
-
-		r := Reservation{
-			Subnet:   sub.Subnet,
-			PublicIP: sub.Attrs.PublicIP,
-		}
-		rsvs = append(rsvs, r)
-	}
-
-	return rsvs, nil
-}
-
 func (m *LocalManager) Name() string {
 	return fmt.Sprintf("Etcd Local Manager with Previous Subnet: %s", m.previousSubnet.String())
 }

subnet/etcdv2/subnet_test.go

@@ -322,120 +322,6 @@ func TestRenewLease(t *testing.T) {
 	t.Fatal("Failed to find acquired lease")
 }
 
-func TestAddReservation(t *testing.T) {
-	msr := newDummyRegistry()
-	sm := NewMockManager(msr)
-
-	ctx, cancel := context.WithCancel(context.Background())
-	defer cancel()
-
-	r := Reservation{
-		Subnet:   newIP4Net("10.4.3.0", 24),
-		PublicIP: ip.MustParseIP4("52.195.12.13"),
-	}
-	if err := sm.AddReservation(ctx, &r); err == nil {
-		t.Fatalf("unexpectedly added a reservation outside of configured network")
-	}
-
-	r.Subnet = newIP4Net("10.3.10.0", 24)
-	if err := sm.AddReservation(ctx, &r); err != nil {
-		t.Fatalf("failed to add reservation: %v", err)
-	}
-
-	// Add the same reservation -- should succeed
-	if err := sm.AddReservation(ctx, &r); err != nil {
-		t.Fatalf("failed to add reservation: %v", err)
-	}
-
-	// Add a reservation with a different public IP -- should fail
-	r2 := r
-	r2.PublicIP = ip.MustParseIP4("52.195.12.17")
-	if err := sm.AddReservation(ctx, &r2); err != ErrLeaseTaken {
-		t.Fatalf("taken add reservation returned: %v", err)
-	}
-
-	attrs := &LeaseAttrs{
-		PublicIP: r.PublicIP,
-	}
-	l, err := sm.AcquireLease(ctx, attrs)
-	if err != nil {
-		t.Fatalf("failed to acquire subnet: %v", err)
-	}
-	if !l.Subnet.Equal(r.Subnet) {
-		t.Fatalf("acquired subnet is not the reserved one: expected %v, got %v", r.Subnet, l.Subnet)
-	}
-	if !l.Expiration.IsZero() {
-		t.Fatalf("acquired lease (prev reserved) has expiration set")
-	}
-}
-
-func TestRemoveReservation(t *testing.T) {
-	msr := newDummyRegistry()
-	sm := NewMockManager(msr)
-
-	ctx, cancel := context.WithCancel(context.Background())
-	defer cancel()
-
-	r := Reservation{
-		Subnet:   newIP4Net("10.3.10.0", 24),
-		PublicIP: ip.MustParseIP4("52.195.12.13"),
-	}
-	if err := sm.AddReservation(ctx, &r); err != nil {
-		t.Fatalf("failed to add reservation: %v", err)
-	}
-
-	if err := sm.RemoveReservation(ctx, r.Subnet); err != nil {
-		t.Fatalf("failed to remove reservation: %v", err)
-	}
-
-	// The node should have a TTL
-	sub, _, err := msr.getSubnet(ctx, r.Subnet)
-	if err != nil {
-		t.Fatalf("getSubnet failed: %v", err)
-	}
-
-	if sub.Expiration.IsZero() {
-		t.Fatalf("removed reservation resulted in no TTL")
-	}
-}
-
-func TestListReservations(t *testing.T) {
-	msr := newDummyRegistry()
-	sm := NewMockManager(msr)
-
-	ctx, cancel := context.WithCancel(context.Background())
-	defer cancel()
-
-	r1 := Reservation{
-		Subnet:   newIP4Net("10.3.10.0", 24),
-		PublicIP: ip.MustParseIP4("52.195.12.13"),
-	}
-	if err := sm.AddReservation(ctx, &r1); err != nil {
-		t.Fatalf("failed to add reservation: %v", err)
-	}
-
-	r2 := Reservation{
-		Subnet:   newIP4Net("10.3.20.0", 24),
-		PublicIP: ip.MustParseIP4("52.195.12.14"),
-	}
-	if err := sm.AddReservation(ctx, &r2); err != nil {
-		t.Fatalf("failed to add reservation: %v", err)
-	}
-
-	rs, err := sm.ListReservations(ctx)
-	if err != nil {
-		if len(rs) != 2 {
-			t.Fatalf("unexpected number of reservations, expected 2, got %v", len(rs))
-		}
-		if !resvEqual(rs[0], r1) && !resvEqual(rs[1], r1) {
-			t.Fatalf("reservation not found")
-		}
-		if !resvEqual(rs[0], r2) && !resvEqual(rs[1], r2) {
-			t.Fatalf("reservation not found")
-		}
-	}
-}
-
 func inAllocatableRange(ctx context.Context, sm Manager, ipn ip.IP4Net) bool {
 	cfg, err := sm.GetNetworkConfig(ctx)
 	if err != nil {
@@ -444,7 +330,3 @@ func inAllocatableRange(ctx context.Context, sm Manager, ipn ip.IP4Net) bool {
 
 	return ipn.IP >= cfg.SubnetMin || ipn.IP <= cfg.SubnetMax
 }
-
-func resvEqual(r1, r2 Reservation) bool {
-	return r1.Subnet.Equal(r2.Subnet) && r1.PublicIP == r2.PublicIP
-}

subnet/kube/kube.go

@@ -311,18 +311,6 @@ func (ksm *kubeSubnetManager) WatchLease(ctx context.Context, sn ip.IP4Net, curs
 	return subnet.LeaseWatchResult{}, ErrUnimplemented
 }
 
-func (ksm *kubeSubnetManager) AddReservation(ctx context.Context, r *subnet.Reservation) error {
-	return ErrUnimplemented
-}
-
-func (ksm *kubeSubnetManager) RemoveReservation(ctx context.Context, subnet ip.IP4Net) error {
-	return ErrUnimplemented
-}
-
-func (ksm *kubeSubnetManager) ListReservations(ctx context.Context) ([]subnet.Reservation, error) {
-	return nil, ErrUnimplemented
-}
-
 func (ksm *kubeSubnetManager) Name() string {
 	return fmt.Sprintf("Kubernetes Subnet Manager - %s", ksm.nodeName)
 }

subnet/subnet.go

@@ -51,11 +51,6 @@ func (l *Lease) Key() string {
 	return MakeSubnetKey(l.Subnet)
 }
 
-type Reservation struct {
-	Subnet   ip.IP4Net
-	PublicIP ip.IP4
-}
-
 type (
 	EventType int
 
@@ -130,8 +125,5 @@ type Manager interface {
 	WatchLease(ctx context.Context, sn ip.IP4Net, cursor interface{}) (LeaseWatchResult, error)
 	WatchLeases(ctx context.Context, cursor interface{}) (LeaseWatchResult, error)
 
-	AddReservation(ctx context.Context, r *Reservation) error
-	RemoveReservation(ctx context.Context, subnet ip.IP4Net) error
-	ListReservations(ctx context.Context) ([]Reservation, error)
 	Name() string
 }