Merge pull request 'dns: introduce jpictl dns sync to update public DNS records' (#25)

A and AAAA only

Reviewed-on: #25

cmd/jpictl/dns.go

@@ -3,6 +3,7 @@ package main
 import (
 	"context"
 	"os"
+	"time"
 
 	"github.com/spf13/cobra"
 
@@ -10,7 +11,13 @@ import (
 	"git.jpi.io/amery/jpictl/pkg/dns"
 )
 
-func newDNSManager(m *cluster.Cluster) (*dns.Manager, error) {
+const (
+	// DNSSyncTimeout specifies how long are we willing to wait for a DNS
+	// synchronization
+	DNSSyncTimeout = 10 * time.Second
+)
+
+func newDNSManager(m *cluster.Cluster, provider dns.Provider) (*dns.Manager, error) {
 	domain := m.Domain
 	if m.Name != "" {
 		domain = m.Name + "." + domain
@@ -21,27 +28,48 @@ func newDNSManager(m *cluster.Cluster) (*dns.Manager, error) {
 		return nil, err
 	}
 
+	if provider != nil {
+		// set provider only  if specified
+		err = dns.WithProvider(provider)(mgr)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	if err := populateDNSManager(mgr, m); err != nil {
+		return nil, err
+	}
+
+	return mgr, nil
+}
+
+func populateDNSManager(mgr *dns.Manager, m *cluster.Cluster) error {
+	var err error
+
+	ctx := context.TODO()
+
 	m.ForEachZone(func(z *cluster.Zone) bool {
 		z.ForEachMachine(func(p *cluster.Machine) bool {
-			err = mgr.AddHost(context.TODO(), z.Name, p.ID, true, p.PublicAddresses...)
+			err = mgr.AddHost(ctx, z.Name, p.ID, true, p.PublicAddresses...)
+			return err != nil
+		})
+
+		return err != nil
+	})
+	if err != nil {
+		return err
+	}
+
+	m.ForEachRegion(func(r *cluster.Region) bool {
+		r.ForEachZone(func(z *cluster.Zone) bool {
+			err = mgr.AddRegion(ctx, r.Name, z.Name)
 			return err != nil
 		})
 
 		return err != nil
 	})
 
-	if err != nil {
-		return nil, err
-	}
-
-	for _, r := range m.Regions {
-		err := mgr.AddRegion(context.TODO(), r.Name, r.Zones()...)
-		if err != nil {
-			return nil, err
-		}
-	}
-
-	return mgr, nil
+	return err
 }
 
 // Command
@@ -51,6 +79,7 @@ var dnsCmd = &cobra.Command{
 
 var dnsWriteCmd = &cobra.Command{
 	Use:    "write",
+	Short:  "dns write generates public DNS records",
 	PreRun: setVerbosity,
 	RunE: func(_ *cobra.Command, _ []string) error {
 		m, err := cfg.LoadZones(true)
@@ -58,7 +87,7 @@ var dnsWriteCmd = &cobra.Command{
 			return err
 		}
 
-		mgr, err := newDNSManager(m)
+		mgr, err := newDNSManager(m, nil)
 		if err != nil {
 			return err
 		}
@@ -68,8 +97,36 @@ var dnsWriteCmd = &cobra.Command{
 	},
 }
 
+var dnsSyncCmd = &cobra.Command{
+	Use:    "sync",
+	Short:  "dns sync updates public DNS records",
+	PreRun: setVerbosity,
+	RunE: func(_ *cobra.Command, _ []string) error {
+		cred, err := dns.DefaultDNSProvider()
+		if err != nil {
+			return err
+		}
+
+		m, err := cfg.LoadZones(true)
+		if err != nil {
+			return err
+		}
+
+		mgr, err := newDNSManager(m, cred)
+		if err != nil {
+			return err
+		}
+
+		ctx, cancel := context.WithTimeout(context.Background(), DNSSyncTimeout)
+		defer cancel()
+
+		return mgr.Sync(ctx)
+	},
+}
+
 func init() {
 	rootCmd.AddCommand(dnsCmd)
 
 	dnsCmd.AddCommand(dnsWriteCmd)
+	dnsCmd.AddCommand(dnsSyncCmd)
 }

go.mod

@@ -2,8 +2,6 @@ module git.jpi.io/amery/jpictl
 
 go 1.19
 
-replace asciigoat.org/ini => ../../../asciigoat.org/ini
-
 require (
 	asciigoat.org/ini v0.2.5
 	darvaza.org/core v0.9.8
@@ -19,6 +17,7 @@ require (
 	github.com/spf13/cobra v1.7.0
 	golang.org/x/crypto v0.12.0
 	golang.org/x/net v0.14.0
+	gopkg.in/gcfg.v1 v1.2.3
 	gopkg.in/yaml.v3 v3.0.1
 )
 
@@ -46,4 +45,5 @@ require (
 	golang.org/x/sys v0.12.0 // indirect
 	golang.org/x/text v0.13.0 // indirect
 	golang.org/x/tools v0.12.0 // indirect
+	gopkg.in/warnings.v0 v0.1.2 // indirect
 )

go.sum

@@ -1,5 +1,7 @@
 asciigoat.org/core v0.3.9 h1:hgDDz4ecm3ZvehX++m8A/IzAt+B5oDPiRtxatzfUHPQ=
 asciigoat.org/core v0.3.9/go.mod h1:CAaHwyw8MpAq4a1MYtN2dxJrsK+hmIdW50OndaQZYPI=
+asciigoat.org/ini v0.2.5 h1:4gRIp9rU+XQt8+HMqZO5R7GavMv9Yl2+N+je6djDIAE=
+asciigoat.org/ini v0.2.5/go.mod h1:gmXzJ9XFqf1NLk5nQkj04USQ4tMtdRJHNQX6vp3DzjU=
 darvaza.org/core v0.9.8 h1:luLxgfUc2pzuusYPo/Z/dC/qr9XZPKpSQw8/kS7zNUM=
 darvaza.org/core v0.9.8/go.mod h1:Dbme64naxeshQfxcVJX9ZT7AiGyIY8kldfuELVtf8mw=
 darvaza.org/resolver v0.5.4 h1:dlSBNV14yYsp7Kg7ipwYOMNsLbrpeXa8Z0HBTa0Ryxs=
@@ -101,6 +103,10 @@ golang.org/x/tools v0.12.0 h1:YW6HUoUmYBpwSgyaGaZq1fHjrBjX1rlpZ54T6mu2kss=
 golang.org/x/tools v0.12.0/go.mod h1:Sc0INKfu04TlqNoRA1hgpFZbhYXHPr4V5DzpSBTPqQM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/gcfg.v1 v1.2.3 h1:m8OOJ4ccYHnx2f4gQwpno8nAX5OGOh7RLaaz0pj3Ogs=
+gopkg.in/gcfg.v1 v1.2.3/go.mod h1:yesOnuUOFQAhST5vPY4nbZsb/huCgGGXlipJsBn0b3o=
+gopkg.in/warnings.v0 v0.1.2 h1:wFXVbFY8DY5/xOe1ECiWdKCzZlxgshcYVNkBHstARME=
+gopkg.in/warnings.v0 v0.1.2/go.mod h1:jksf8JmL6Qr/oQM2OXTHunEvvTAsrWBLb6OOjuVWRNI=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
 gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
 gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

pkg/cluster/regions.go

@@ -1,5 +1,10 @@
 package cluster
 
+var (
+	_ MachineIterator = (*Region)(nil)
+	_ ZoneIterator    = (*Region)(nil)
+)
+
 // Region represents a group of zones geographically related
 type Region struct {
 	m     *Cluster
@@ -9,13 +14,41 @@ type Region struct {
 	Regions []string `json:",omitempty" yaml:",omitempty"`
 }
 
-// Zones ...
-func (r *Region) Zones() []string {
-	out := make([]string, len(r.zones))
-	for i := range r.zones {
-		out[i] = r.zones[i].Name
+// ForEachRegion calls a function for each Region of the cluster
+// until instructed to terminate the loop
+func (m *Cluster) ForEachRegion(fn func(r *Region) bool) {
+	for i := range m.Regions {
+		r := &m.Regions[i]
+		if fn(r) {
+			return
+		}
+	}
+}
+
+// ForEachMachine calls a function for each Machine in the region
+// until instructed to terminate the loop
+func (r *Region) ForEachMachine(fn func(*Machine) bool) {
+	r.ForEachZone(func(z *Zone) bool {
+		var term bool
+
+		z.ForEachMachine(func(p *Machine) bool {
+			term = fn(p)
+			return term
+		})
+
+		return term
+	})
+}
+
+// ForEachZone calls a function for each Zone in the region
+// until instructed to terminate the loop
+func (r *Region) ForEachZone(fn func(*Zone) bool) {
+	for _, p := range r.zones {
+		if fn(p) {
+			// terminate
+			return
+		}
 	}
-	return out
 }
 
 func (m *Cluster) initRegions(_ *ScanOptions) error {

pkg/dns/dns.go

@@ -1,34 +1,38 @@
 // Package dns manages DNS entries for the cluster
 package dns
 
-import "net/netip"
+import (
+	"fmt"
+	"net/netip"
+)
 
-// // A Config defines a Region
-//
-//	type Config struct {
-//		// Name is the identifier of this Region
-//		Name string
-//		// Regions are a list of (sub)regions that belong to this Region
-//		Regions []string
-//		// Zones are a list of Zones that directly belong to this Region
-//		Zones []string
-//	}
-//
-//	type Region struct {
-//		Name string
-//	}
-
-// Zone represents a set of machines with high affinity
+// Zone represents a set of hosts with high affinity
 type Zone struct {
 	Name string
 
-	Machines map[int]*Machine
+	Hosts map[int]*Host
 }
 
-// Machine represents a member of the cluster
-type Machine struct {
-	ID int
+func (z *Zone) String() string {
+	if z == nil {
+		return "undetermined"
+	}
+	return z.Name
+}
 
+// Host represents a member of the cluster
+type Host struct {
+	zone *Zone
+
+	ID     int
 	Active bool
 	Addrs  []netip.Addr
 }
+
+func (p *Host) String() string {
+	if p == nil {
+		return "undetermined"
+	}
+
+	return fmt.Sprintf("%s-%v", p.zone, p.ID)
+}

pkg/dns/host.go

@@ -1,41 +0,0 @@
-package dns
-
-import (
-	"context"
-	"io/fs"
-	"net/netip"
-)
-
-// AddHost registers a machine
-func (mgr *Manager) AddHost(_ context.Context, zone string, id int,
-	active bool, addrs ...netip.Addr) error {
-	//
-	if zone == "" || id <= 0 {
-		return fs.ErrInvalid
-	}
-
-	z, ok := mgr.zones[zone]
-	if !ok {
-		z = &Zone{
-			Name:     zone,
-			Machines: make(map[int]*Machine),
-		}
-
-		mgr.zones[zone] = z
-	}
-
-	z.Machines[id] = &Machine{
-		ID:     id,
-		Active: active,
-		Addrs:  SortAddrSlice(addrs),
-	}
-
-	return nil
-}
-
-// AddRegion specifies a new region and the zones it contains
-func (mgr *Manager) AddRegion(_ context.Context, region string, zones ...string) error {
-	mgr.l.Debug().WithField("region", region).WithField("zones", zones).Print()
-	mgr.regions[region] = append(mgr.regions[region], zones...)
-	return nil
-}

pkg/dns/manager.go

@@ -1,9 +1,11 @@
 package dns
 
 import (
+	"context"
 	"errors"
+	"io/fs"
+	"net/netip"
 	"strings"
-	"sync"
 
 	"darvaza.org/core"
 	"darvaza.org/slog"
@@ -13,8 +15,6 @@ import (
 
 // Manager is a DNS Manager instance
 type Manager struct {
-	mu sync.Mutex
-
 	domain  string
 	suffix  string
 	zones   map[string]*Zone
@@ -29,10 +29,7 @@ type ManagerOption func(*Manager) error
 
 func newErrorManagerOption(err error, hint string) ManagerOption {
 	return func(*Manager) error {
-		if hint != "" {
-			err = core.Wrap(err, hint)
-		}
-		return err
+		return core.Wrap(err, hint)
 	}
 }
 
@@ -77,9 +74,6 @@ func (mgr *Manager) setDefaults() error {
 		return errors.New("domain not specified")
 	}
 
-	mgr.zones = make(map[string]*Zone)
-	mgr.regions = make(map[string][]string)
-
 	for _, opt := range opts {
 		if err := opt(mgr); err != nil {
 			return err
@@ -109,7 +103,10 @@ func WithDomain(domain string) ManagerOption {
 
 // NewManager creates a DNS manager with the
 func NewManager(opts ...ManagerOption) (*Manager, error) {
-	mgr := new(Manager)
+	mgr := &Manager{
+		zones:   make(map[string]*Zone),
+		regions: make(map[string][]string),
+	}
 
 	for _, opt := range opts {
 		if err := opt(mgr); err != nil {
@@ -122,3 +119,55 @@ func NewManager(opts ...ManagerOption) (*Manager, error) {
 	}
 	return mgr, nil
 }
+
+// AddHost registers a host
+func (mgr *Manager) AddHost(_ context.Context, zone string, id int,
+	active bool, addrs ...netip.Addr) error {
+	//
+	if zone == "" || id <= 0 {
+		return fs.ErrInvalid
+	}
+
+	z, ok := mgr.zones[zone]
+	if !ok {
+		z = &Zone{
+			Name:  zone,
+			Hosts: make(map[int]*Host),
+		}
+
+		mgr.zones[zone] = z
+	}
+
+	p := &Host{
+		zone:   z,
+		ID:     id,
+		Active: active,
+		Addrs:  SortAddrSlice(addrs),
+	}
+	z.Hosts[id] = p
+
+	if log, ok := mgr.l.Debug().WithEnabled(); ok {
+		log.WithField("subsystem", "dns").
+			WithField("zone", zone).
+			WithField("host", p.String()).
+			WithField("active", active).
+			Print()
+	}
+
+	return nil
+}
+
+// AddRegion specifies a new region and the zones it contains
+func (mgr *Manager) AddRegion(_ context.Context, region string, zones ...string) error {
+	mgr.regions[region] = append(mgr.regions[region], zones...)
+
+	if log, ok := mgr.l.Debug().WithEnabled(); ok {
+		for _, zoneName := range zones {
+			log.WithField("subsystem", "dns").
+				WithField("region", region).
+				WithField("zone", zoneName).Print()
+		}
+	}
+
+	return nil
+}

pkg/dns/provider.go

@@ -18,6 +18,8 @@ const (
 type Provider interface {
 	libdns.RecordGetter
 	libdns.RecordDeleter
+	libdns.RecordSetter
+	libdns.RecordAppender
 }
 
 // DefaultDNSProvider returns a cloudflare DNS provider

pkg/dns/record.go

@@ -1,7 +1,9 @@
 package dns
 
 import (
+	"bytes"
 	"fmt"
+	"io"
 	"net/netip"
 	"sort"
 	"time"
@@ -10,7 +12,11 @@ import (
 	"github.com/libdns/libdns"
 )
 
-// SortAddrSlice ...
+func (mgr *Manager) fqdn(name string) string {
+	return fmt.Sprintf("%s.%s.", name, mgr.domain)
+}
+
+// SortAddrSlice sorts a slice of [netip.Addr]
 func SortAddrSlice(s []netip.Addr) []netip.Addr {
 	sort.Slice(s, func(i, j int) bool {
 		return s[i].Less(s[j])
@@ -18,6 +24,46 @@ func SortAddrSlice(s []netip.Addr) []netip.Addr {
 	return s
 }
 
+// SortAddrRecords sorts a slice of [AddrRecord]
+// by Name and Address
+func SortAddrRecords(s []AddrRecord) []AddrRecord {
+	sort.Slice(s, func(i, j int) bool {
+		return s[i].Name < s[j].Name
+	})
+
+	for _, p := range s {
+		SortAddrSlice(p.Addr)
+	}
+
+	return s
+}
+
+// SortRegions sorts regions. first by length those 3-character
+// or shorter, and then by length. It's mostly aimed at
+// supporting ISO-3166 order
+func SortRegions(regions []string) []string {
+	sort.Slice(regions, func(i, j int) bool {
+		r1, r2 := regions[i], regions[j]
+
+		switch {
+		case len(r1) < 4:
+			switch {
+			case len(r1) < len(r2):
+				return true
+			case len(r1) > len(r2):
+				return false
+			default:
+				return r1 < r2
+			}
+		case len(r2) < 4:
+			return false
+		default:
+			return r1 < r2
+		}
+	})
+	return regions
+}
+
 // AddrRecord represents an A or AAAA record
 type AddrRecord struct {
 	Name string
@@ -44,6 +90,43 @@ func (rr *AddrRecord) Export() []libdns.Record {
 	return out
 }
 
+// WriteTo writes the record in BIND notation
+func (rr *AddrRecord) WriteTo(w io.Writer) (int64, error) {
+	var total int
+	for _, addr := range rr.Addr {
+		n, err := fmt.Fprint(w,
+			rr.Name, "\t",
+			1, "\t",
+			core.IIf(addr.Is6(), "AAAA", "A"), "\t",
+			addr.String(), "\n")
+
+		switch {
+		case err != nil:
+			return 0, err
+		case n > 0:
+			total += n
+		}
+	}
+
+	return int64(total), nil
+}
+
+// String converts the record into BIND entries
+func (rr *AddrRecord) String() string {
+	var buf bytes.Buffer
+	_, _ = rr.WriteTo(&buf)
+	return buf.String()
+}
+
+func (mgr *Manager) genRegionsSorted() []string {
+	regions := make([]string, 0, len(mgr.regions))
+	for name := range mgr.regions {
+		regions = append(regions, name)
+	}
+
+	return SortRegions(regions)
+}
+
 func (mgr *Manager) genAllAddrRecords() []AddrRecord {
 	var out []AddrRecord
 
@@ -51,8 +134,8 @@ func (mgr *Manager) genAllAddrRecords() []AddrRecord {
 
 	// zones
 	for _, z := range mgr.zones {
-		// machines
-		s := mgr.genZoneMachineRecords(z)
+		// hosts
+		s := mgr.genZoneHostRecords(z)
 		out = append(out, s...)
 
 		// zone alias
@@ -68,11 +151,10 @@ func (mgr *Manager) genAllAddrRecords() []AddrRecord {
 		cache[name] = addrs
 	}
 
-	// regions
-	for name, zones := range mgr.regions {
+	for _, name := range mgr.genRegionsSorted() {
 		var addrs []netip.Addr
 
-		for _, z := range zones {
+		for _, z := range mgr.regions[name] {
 			addrs = append(addrs, cache[z]...)
 		}
 
@@ -85,18 +167,14 @@ func (mgr *Manager) genAllAddrRecords() []AddrRecord {
 		out = append(out, rec)
 	}
 
-	// sort
-	sort.Slice(out, func(i, j int) bool {
-		return out[i].Name < out[j].Name
-	})
-
+	SortAddrRecords(out)
 	return out
 }
 
 func (*Manager) genZoneAddresses(z *Zone) []netip.Addr {
 	var out []netip.Addr
 
-	for _, p := range z.Machines {
+	for _, p := range z.Hosts {
 		if p.Active {
 			out = append(out, p.Addrs...)
 		}
@@ -106,16 +184,30 @@ func (*Manager) genZoneAddresses(z *Zone) []netip.Addr {
 	return out
 }
 
-func (mgr *Manager) genZoneMachineRecords(z *Zone) []AddrRecord {
-	out := make([]AddrRecord, 0, len(z.Machines))
+func (mgr *Manager) genZoneHostRecords(z *Zone) []AddrRecord {
+	out := make([]AddrRecord, 0, len(z.Hosts))
 
-	for _, p := range z.Machines {
+	for _, p := range z.Hosts {
 		rec := AddrRecord{
-			Name: fmt.Sprintf("%s-%v%s", z.Name, p.ID, mgr.suffix),
+			Name: p.String() + mgr.suffix,
 			Addr: p.Addrs,
 		}
 		out = append(out, rec)
 	}
 
+	SortAddrRecords(out)
 	return out
 }
+
+func (mgr *Manager) genRegionAddressesCached(name string,
+	zones map[string][]netip.Addr) []netip.Addr {
+	//
+	var addrs []netip.Addr
+
+	for _, zoneName := range mgr.regions[name] {
+		addrs = append(addrs, zones[zoneName]...)
+	}
+
+	SortAddrSlice(addrs)
+	return addrs
+}

pkg/dns/sync.go

@@ -0,0 +1,347 @@
+package dns
+
+import (
+	"context"
+	"errors"
+	"net/netip"
+	"sort"
+	"strings"
+	"time"
+
+	"darvaza.org/core"
+	"darvaza.org/slog"
+	"github.com/libdns/libdns"
+)
+
+// SyncAddrRecord is similar to AddrRecord but include libdns.Record details
+// fetched from the Provider
+type SyncAddrRecord struct {
+	Name  string
+	Addrs []SyncAddr
+}
+
+// SyncAddr extends netip.Addr with ID and TTL fetched from the Provider
+type SyncAddr struct {
+	ID   string
+	Addr netip.Addr
+	TTL  time.Duration
+}
+
+// Export assembles a libdns.Record
+func (rec *SyncAddr) Export(name string) libdns.Record {
+	return libdns.Record{
+		ID:    rec.ID,
+		Name:  name,
+		Type:  core.IIf(rec.Addr.Is6(), "AAAA", "A"),
+		TTL:   time.Second,
+		Value: rec.Addr.String(),
+	}
+}
+
+// SortSyncAddrSlice sorts a slice of [SyncAddr] by its address
+func SortSyncAddrSlice(s []SyncAddr) []SyncAddr {
+	sort.Slice(s, func(i, j int) bool {
+		a1 := s[i].Addr
+		a2 := s[j].Addr
+		return a1.Less(a2)
+	})
+	return s
+}
+
+// GetRecords pulls all the address records on DNS for our domain
+func (mgr *Manager) GetRecords(ctx context.Context) ([]SyncAddrRecord, error) {
+	if mgr.p == nil {
+		return nil, errors.New("dns provider not specified")
+	}
+
+	recs, err := mgr.p.GetRecords(ctx, mgr.domain)
+	if err != nil {
+		return nil, err
+	}
+
+	return mgr.filteredRecords(recs)
+}
+
+// AsSyncAddr converts a A or AAAA [libdns.Record] into a [SyncAddr]
+func (mgr *Manager) AsSyncAddr(rr libdns.Record) (SyncAddr, bool, error) {
+	var out SyncAddr
+	var addr netip.Addr
+
+	// skip non-address types
+	if rr.Type != "A" && rr.Type != "AAAA" {
+		return out, false, nil
+	}
+
+	// skip entries not containing our suffix
+	if mgr.suffix != "" {
+		if !strings.HasSuffix(rr.Name, mgr.suffix) {
+			return out, false, nil
+		}
+	}
+
+	err := addr.UnmarshalText([]byte(rr.Value))
+	if err != nil {
+		// invalid address on A or AAAA record
+		return out, false, err
+	}
+
+	out = SyncAddr{
+		ID:   rr.ID,
+		TTL:  rr.TTL,
+		Addr: addr,
+	}
+
+	return out, true, nil
+}
+
+func (mgr *Manager) filteredRecords(recs []libdns.Record) ([]SyncAddrRecord, error) {
+	// filter and convert
+	cache := make(map[string][]SyncAddr)
+	for _, rr := range recs {
+		addr, ok, err := mgr.AsSyncAddr(rr)
+		switch {
+		case err != nil:
+			// skip invalid addresses
+			mgr.l.Error().
+				WithField("subsystem", "dns").
+				WithField(slog.ErrorFieldName, err).
+				WithField("name", rr.Name).
+				WithField("type", rr.Type).
+				WithField("addr", rr.Value).
+				Print()
+		case ok:
+			// store
+			cache[rr.Name] = append(cache[rr.Name], addr)
+		}
+	}
+
+	// prepare records
+	out := make([]SyncAddrRecord, len(cache))
+	names := make([]string, 0, len(cache))
+	for name := range cache {
+		names = append(names, name)
+	}
+	sort.Strings(names)
+
+	for i, name := range names {
+		addrs := cache[name]
+
+		out[i] = SyncAddrRecord{
+			Name:  name,
+			Addrs: SortSyncAddrSlice(addrs),
+		}
+	}
+
+	return out, nil
+}
+
+// Sync updates all the address records on DNS for our domain
+func (mgr *Manager) Sync(ctx context.Context) error {
+	current, err := mgr.GetRecords(ctx)
+	if err != nil {
+		return core.Wrap(err, "GetRecords")
+	}
+
+	goal := mgr.genAllAddrRecords()
+	for _, p := range makeSyncMap(current, goal) {
+		err := mgr.doSync(ctx, p.Name, p.Before, p.After)
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func (mgr *Manager) doSync(ctx context.Context, name string,
+	before []SyncAddr, after []netip.Addr) error {
+	//
+	var err error
+
+	for _, a := range after {
+		before, err = mgr.doSyncUpdateOrInsert(ctx, name, a, before)
+		if err != nil {
+			return err
+		}
+	}
+
+	for _, b := range before {
+		err = mgr.doSyncRemove(ctx, name, b)
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func (mgr *Manager) doSyncUpdateOrInsert(ctx context.Context, name string,
+	addr netip.Addr, addrs []SyncAddr) ([]SyncAddr, error) {
+	//
+	var err error
+
+	i, ok := findSyncAddrSorted(addr, addrs)
+	if ok {
+		rec := addrs[i]
+
+		addrs = append(addrs[:i], addrs[i+1:]...)
+		err = mgr.doSyncUpdate(ctx, name, addr, rec)
+	} else {
+		err = mgr.doSyncInsert(ctx, name, addr)
+	}
+
+	return addrs, err
+}
+
+func (mgr *Manager) doSyncUpdate(ctx context.Context, name string,
+	addr netip.Addr, rec SyncAddr) error {
+	//
+	var log slog.Logger
+	var msg string
+	var err error
+
+	if rec.TTL != time.Second {
+		// amend TTL
+
+		// TODO: batch updates
+		_, err = mgr.p.SetRecords(ctx, mgr.domain, []libdns.Record{
+			rec.Export(name),
+		})
+
+		if err == nil {
+			log = mgr.l.Info()
+			msg = "Updated"
+		} else {
+			log = mgr.l.Error().
+				WithField(slog.ErrorFieldName, err)
+			msg = "Failed"
+		}
+	} else {
+		log = mgr.l.Info()
+		msg = "OK"
+	}
+
+	log.
+		WithField("subsystem", "dns").
+		WithField("name", name).
+		WithField("addr", addr).
+		Print(msg)
+
+	return err
+}
+
+func (mgr *Manager) doSyncInsert(ctx context.Context, name string,
+	addr netip.Addr) error {
+	//
+	var log slog.Logger
+	var msg string
+
+	rec := libdns.Record{
+		Name:  name,
+		Type:  core.IIf(addr.Is6(), "AAAA", "A"),
+		TTL:   time.Second,
+		Value: addr.String(),
+	}
+
+	_, err := mgr.p.AppendRecords(ctx, mgr.domain, []libdns.Record{
+		rec,
+	})
+
+	if err != nil {
+		log = mgr.l.Error().
+			WithField(slog.ErrorFieldName, err)
+		msg = "Failed to Add"
+	} else {
+		log = mgr.l.Info()
+		msg = "Added"
+	}
+
+	log.
+		WithField("subsystem", "dns").
+		WithField("name", name).
+		WithField("addr", addr).
+		Print(msg)
+	return err
+}
+
+func (mgr *Manager) doSyncRemove(ctx context.Context, name string,
+	rec SyncAddr) error {
+	//
+	var log slog.Logger
+	var msg string
+
+	// TODO: batch deletes
+	_, err := mgr.p.DeleteRecords(ctx, mgr.domain, []libdns.Record{
+		rec.Export(name),
+	})
+
+	if err != nil {
+		log = mgr.l.Error().
+			WithField(slog.ErrorFieldName, err)
+		msg = "Failed to Delete"
+	} else {
+		log = mgr.l.Warn()
+		msg = "Deleted"
+	}
+
+	log.
+		WithField("subsystem", "dns").
+		WithField("name", name).
+		WithField("addr", rec.Addr).
+		Print(msg)
+	return err
+}
+
+func findSyncAddrSorted(target netip.Addr, addrs []SyncAddr) (int, bool) {
+	for i, a := range addrs {
+		switch target.Compare(a.Addr) {
+		case 0:
+			// match
+			return i, true
+		case -1:
+			// miss
+			return -1, false
+		default:
+			// next
+		}
+	}
+
+	return -1, false
+}
+
+type syncMapEntry struct {
+	Name   string
+	Before []SyncAddr
+	After  []netip.Addr
+}
+
+func makeSyncMap(current []SyncAddrRecord,
+	goal []AddrRecord) map[string]syncMapEntry {
+	//
+	data := make(map[string]syncMapEntry)
+
+	for _, cur := range current {
+		me, ok := data[cur.Name]
+		if !ok {
+			me = syncMapEntry{
+				Name: cur.Name,
+			}
+		}
+
+		me.Before = append(me.Before, cur.Addrs...)
+		data[cur.Name] = me
+	}
+
+	for _, rr := range goal {
+		me, ok := data[rr.Name]
+		if !ok {
+			me = syncMapEntry{
+				Name: rr.Name,
+			}
+		}
+		me.After = append(me.After, rr.Addr...)
+		data[rr.Name] = me
+	}
+
+	return data
+}

pkg/dns/write.go

@@ -4,32 +4,59 @@ import (
 	"bytes"
 	"fmt"
 	"io"
-	"time"
-
-	"github.com/libdns/libdns"
+	"net/netip"
 )
 
 // WriteTo writes the DNS data for the cluster
 func (mgr *Manager) WriteTo(w io.Writer) (int64, error) {
 	var buf bytes.Buffer
 
-	records := mgr.genAllAddrRecords()
-	for i := range records {
-		r := &records[i]
-		r.Name = fmt.Sprintf("%s.%s.", r.Name, mgr.domain)
+	cache := make(map[string][]netip.Addr)
+
+	// zones
+	for _, z := range mgr.zones {
+		mgr.writeZoneHosts(&buf, z)
+
+		// zone alias
+		addrs := mgr.genZoneAddresses(z)
+		zoneName := z.Name
+
+		rr := AddrRecord{
+			Name: mgr.fqdn(zoneName + mgr.suffix),
+			Addr: addrs,
+		}
+		_, _ = rr.WriteTo(&buf)
+
+		// and cache for regions
+		cache[zoneName] = addrs
 	}
 
-	for _, rr1 := range records {
-		for _, rr2 := range rr1.Export() {
-			writeRecord(&buf, rr2)
-		}
+	// regions, sorted
+	for _, name := range mgr.genRegionsSorted() {
+		addrs := mgr.genRegionAddressesCached(name, cache)
+
+		mgr.writeRegionAddresses(&buf, name, addrs)
 	}
 
 	return buf.WriteTo(w)
 }
 
-func writeRecord(w io.Writer, rr libdns.Record) {
-	_, _ = fmt.Fprintf(w, "%s\t%v\tIN\t%s\t%s\n",
-		rr.Name, int(rr.TTL/time.Second),
-		rr.Type, rr.Value)
+func (mgr *Manager) writeZoneHosts(w io.Writer, z *Zone) {
+	_, _ = fmt.Fprintf(w, ";\n; %s\n;\n", z.Name)
+
+	for _, rr := range mgr.genZoneHostRecords(z) {
+		rr.Name = mgr.fqdn(rr.Name)
+		_, _ = rr.WriteTo(w)
+	}
+}
+
+func (mgr *Manager) writeRegionAddresses(w io.Writer, name string, addrs []netip.Addr) {
+	_, _ = fmt.Fprintf(w, "; %s\n", name)
+
+	rr := AddrRecord{
+		Name: mgr.fqdn(name + mgr.suffix),
+		Addr: addrs,
+	}
+
+	_, _ = rr.WriteTo(w)
 }

pkg/wireguard/config.go

@@ -2,6 +2,7 @@ package wireguard
 
 import (
 	"bytes"
+	"errors"
 	"fmt"
 	"io"
 	"net/netip"
@@ -9,8 +10,8 @@ import (
 	"strings"
 	"text/template"
 
-	"asciigoat.org/ini/basic"
 	"darvaza.org/core"
+	"gopkg.in/gcfg.v1"
 )
 
 var configTemplate = template.Must(template.New("config").Funcs(template.FuncMap{
@@ -106,11 +107,6 @@ func (ep EndpointAddress) String() string {
 	}
 }
 
-// UnmarshalText loads an endpoint address from text data
-func (ep *EndpointAddress) UnmarshalText(b []byte) error {
-	return ep.FromString(string(b))
-}
-
 // FromString sets the EndpointAddress from a given "[host]:port"
 func (ep *EndpointAddress) FromString(s string) error {
 	host, port, err := core.SplitHostPort(s)
@@ -131,6 +127,98 @@ func (ep *EndpointAddress) FromString(s string) error {
 	return nil
 }
 
+type intermediateConfig struct {
+	Interface interfaceConfig
+	Peer      peersConfig
+}
+
+func (v *intermediateConfig) Export() (*Config, error) {
+	var out Config
+	var err error
+
+	// Interface
+	out.Interface, err = v.Interface.Export()
+	if err != nil {
+		return nil, err
+	}
+
+	// Peers
+	peers, ok := v.PeersCount()
+	if !ok {
+		return nil, errors.New("inconsistent Peer data")
+	}
+
+	for i := 0; i < peers; i++ {
+		p, err := v.ExportPeer(i)
+		if err != nil {
+			err = core.Wrapf(err, "Peer[%v]:", i)
+			return nil, err
+		}
+
+		out.Peer = append(out.Peer, p)
+	}
+
+	return &out, nil
+}
+
+type interfaceConfig struct {
+	Address    netip.Addr
+	PrivateKey string
+	ListenPort uint16
+}
+
+func (p interfaceConfig) Export() (InterfaceConfig, error) {
+	var err error
+
+	out := InterfaceConfig{
+		Address:    p.Address,
+		ListenPort: p.ListenPort,
+	}
+
+	out.PrivateKey, err = PrivateKeyFromBase64(p.PrivateKey)
+	if err != nil {
+		err = core.Wrap(err, "PrivateKey")
+		return InterfaceConfig{}, err
+	}
+
+	return out, nil
+}
+
+type peersConfig struct {
+	PublicKey  []string
+	Endpoint   []string
+	AllowedIPs []string
+}
+
+func (v *intermediateConfig) ExportPeer(i int) (PeerConfig, error) {
+	var out PeerConfig
+
+	// Endpoint
+	s := v.Peer.Endpoint[i]
+	err := out.Endpoint.FromString(s)
+	if err != nil {
+		err = core.Wrap(err, "Endpoint")
+		return out, err
+	}
+
+	// PublicKey
+	out.PublicKey, err = PublicKeyFromBase64(v.Peer.PublicKey[i])
+	if err != nil {
+		err = core.Wrap(err, "PublicKey")
+		return out, err
+	}
+
+	// AllowedIPs
+	s = v.Peer.AllowedIPs[i]
+	out.AllowedIPs, err = parseAllowedIPs(s)
+	if err != nil {
+		err = core.Wrap(err, "AllowedIPs")
+		return out, err
+	}
+
+	return out, nil
+}
+
 func parseAllowedIPs(data string) ([]netip.Prefix, error) {
 	var out []netip.Prefix
 
@@ -147,17 +235,25 @@ func parseAllowedIPs(data string) ([]netip.Prefix, error) {
 	return out, nil
 }
 
+func (v *intermediateConfig) PeersCount() (int, bool) {
+	c0 := len(v.Peer.Endpoint)
+	c1 := len(v.Peer.PublicKey)
+	c2 := len(v.Peer.AllowedIPs)
+
+	if c0 != c1 || c1 != c2 {
+		return 0, false
+	}
+
+	return c0, true
+}
+
 // NewConfigFromReader parses a wgN.conf file
 func NewConfigFromReader(r io.Reader) (*Config, error) {
-	doc, err := basic.Decode(r)
-	if err != nil {
+	temp := &intermediateConfig{}
+
+	if err := gcfg.ReadInto(temp, r); err != nil {
 		return nil, err
 	}
 
-	cfg, err := newConfigFromDocument(doc)
-	if err != nil {
-		return nil, err
-	}
-
-	return cfg, nil
+	return temp.Export()
 }

pkg/wireguard/config_parser.go

@@ -1,169 +0,0 @@
-package wireguard
-
-import (
-	"io/fs"
-	"strconv"
-
-	"asciigoat.org/ini/basic"
-	"darvaza.org/core"
-)
-
-type sectionHandler func(*Config, *basic.Section) error
-
-var sectionMap = map[string]func(*Config, *basic.Section) error{
-	"Interface": loadInterfaceConfSection,
-	"Peer":      loadPeerConfSection,
-}
-
-func loadConfSection(out *Config, src *basic.Section) error {
-	h, ok := sectionMap[src.Key]
-	if !ok {
-		return core.Wrapf(fs.ErrInvalid, "unknown section %q", src.Key)
-	}
-
-	return h(out, src)
-}
-
-func loadInterfaceConfSection(out *Config, src *basic.Section) error {
-	var cfg InterfaceConfig
-
-	for _, field := range src.Fields {
-		if err := loadInterfaceConfField(&cfg, field); err != nil {
-			return core.Wrap(err, "Interface")
-		}
-	}
-
-	out.Interface = cfg
-	return nil
-}
-
-func loadPeerConfSection(out *Config, src *basic.Section) error {
-	var cfg PeerConfig
-
-	for _, field := range src.Fields {
-		if err := loadPeerConfField(&cfg, field); err != nil {
-			return core.Wrapf(err, "Peer[%v]", len(out.Peer))
-		}
-	}
-
-	out.Peer = append(out.Peer, cfg)
-	return nil
-}
-
-// revive:disable:cyclomatic
-// revive:disable:cognitive-complexity
-
-func loadInterfaceConfField(cfg *InterfaceConfig, field basic.Field) error {
-	// revive:enable:cyclomatic
-	// revive:enable:cognitive-complexity
-
-	// TODO: refactor when asciigoat's ini parser learns to do reflection
-	switch field.Key {
-	case "Address":
-		if !core.IsZero(cfg.Address) {
-			return core.Wrapf(fs.ErrInvalid, "duplicate field %q", field.Key)
-		}
-
-		err := cfg.Address.UnmarshalText([]byte(field.Value))
-		switch {
-		case err != nil:
-			return core.Wrap(err, field.Key)
-		default:
-			return nil
-		}
-	case "PrivateKey":
-		if !core.IsZero(cfg.PrivateKey) {
-			return core.Wrapf(fs.ErrInvalid, "duplicate field %q", field.Key)
-		}
-
-		err := cfg.PrivateKey.UnmarshalText([]byte(field.Value))
-		switch {
-		case err != nil:
-			return core.Wrap(err, field.Key)
-		default:
-			return nil
-		}
-	case "ListenPort":
-		if cfg.ListenPort > 0 {
-			return core.Wrapf(fs.ErrInvalid, "duplicate field %q", field.Key)
-		}
-
-		u64, err := strconv.ParseUint(field.Value, 10, 16)
-		switch {
-		case err != nil:
-			return core.Wrap(err, field.Key)
-		case u64 == 0:
-			return core.Wrapf(fs.ErrInvalid, "invalid %q value", field.Key)
-		default:
-			cfg.ListenPort = uint16(u64)
-			return nil
-		}
-	default:
-		return core.Wrapf(fs.ErrInvalid, "unknown field %q", field.Key)
-	}
-}
-
-// revive:disable:cyclomatic
-// revive:disable:cognitive-complexity
-
-func loadPeerConfField(cfg *PeerConfig, field basic.Field) error {
-	// revive:enable:cyclomatic
-	// revive:enable:cognitive-complexity
-
-	switch field.Key {
-	case "PublicKey":
-		if !core.IsZero(cfg.PublicKey) {
-			return core.Wrapf(fs.ErrInvalid, "duplicate field %q", field.Key)
-		}
-
-		err := cfg.PublicKey.UnmarshalText([]byte(field.Value))
-		switch {
-		case err != nil:
-			return core.Wrap(err, field.Key)
-		default:
-			return nil
-		}
-	case "Endpoint":
-		if cfg.Endpoint.String() != "" {
-			return core.Wrapf(fs.ErrInvalid, "duplicate field %q", field.Key)
-		}
-
-		err := cfg.Endpoint.UnmarshalText([]byte(field.Value))
-		switch {
-		case err != nil:
-			return core.Wrap(err, field.Key)
-		default:
-			return nil
-		}
-	case "AllowedIPs":
-		s, err := parseAllowedIPs(field.Value)
-		switch {
-		case err != nil:
-			return core.Wrap(err, field.Key)
-		case len(s) > 0:
-			cfg.AllowedIPs = append(cfg.AllowedIPs, s...)
-			return nil
-		}
-	default:
-		return core.Wrapf(fs.ErrInvalid, "unknown field %q", field.Key)
-	}
-	return nil
-}
-
-func newConfigFromDocument(doc *basic.Document) (*Config, error) {
-	var out Config
-
-	if len(doc.Global) > 0 {
-		err := core.Wrap(fs.ErrInvalid, "fields before the first section")
-		return nil, err
-	}
-
-	for i := range doc.Sections {
-		src := &doc.Sections[i]
-		if err := loadConfSection(&out, src); err != nil {
-			return nil, err
-		}
-	}
-
-	return &out, nil
-}

pkg/wireguard/keys.go

@@ -51,30 +51,6 @@ func (pub PublicKey) String() string {
 	}
 }
 
-// UnmarshalText loads the value from base64
-func (key *PrivateKey) UnmarshalText(b []byte) error {
-	v, err := PrivateKeyFromBase64(string(b))
-	switch {
-	case err != nil:
-		return err
-	default:
-		*key = v
-		return nil
-	}
-}
-
-// UnmarshalText loads the value from base64
-func (pub *PublicKey) UnmarshalText(b []byte) error {
-	v, err := PublicKeyFromBase64(string(b))
-	switch {
-	case err != nil:
-		return err
-	default:
-		*pub = v
-		return nil
-	}
-}
-
 // MarshalJSON encodes the key for JSON, omitting empty.
 func (key PrivateKey) MarshalJSON() ([]byte, error) {
 	return encodeKeyJSON(key.String())