WIP

Signed-off-by: Alejandro Mery <amery@jpi.io>

cmd/jpictl/dns.go

@@ -0,0 +1,116 @@
+package main
+
+import (
+	"context"
+	"os"
+	"time"
+
+	"github.com/spf13/cobra"
+
+	"git.jpi.io/amery/jpictl/pkg/cluster"
+	"git.jpi.io/amery/jpictl/pkg/dns"
+)
+
+const (
+	DNSTimeout = 10 * time.Second
+)
+
+func newDNSManager(ctx context.Context, m *cluster.Cluster) (*dns.Manager, error) {
+	domain := m.Domain
+	if m.Name != "" {
+		domain = m.Name + "." + domain
+	}
+
+	mgr, err := dns.NewManager(dns.WithDomain(domain), dns.WithLogger(log))
+	if err != nil {
+		return nil, err
+	}
+
+	m.ForEachZone(func(z *cluster.Zone) bool {
+		z.ForEachMachine(func(p *cluster.Machine) bool {
+			err = mgr.AddHost(ctx, z.Name, p.ID, true, p.PublicAddresses...)
+			return err != nil
+		})
+
+		return err != nil
+	})
+
+	if err != nil {
+		return nil, err
+	}
+
+	return mgr, nil
+}
+
+// Command
+var dnsCmd = &cobra.Command{
+	Use: "dns",
+}
+
+var dnsSyncCmd = &cobra.Command{
+	Use:    "sync",
+	PreRun: setVerbosity,
+	RunE: func(_ *cobra.Command, _ []string) error {
+		m, err := cfg.LoadZones(true)
+		if err != nil {
+			return err
+		}
+
+		ctx, cancel := context.WithTimeout(context.Background(), DNSTimeout)
+		defer cancel()
+
+		_, err = newDNSManager(ctx, m)
+		if err != nil {
+			return err
+		}
+
+		return nil
+	},
+}
+
+var dnsWriteCmd = &cobra.Command{
+	Use:    "write",
+	PreRun: setVerbosity,
+	RunE: func(_ *cobra.Command, _ []string) error {
+		m, err := cfg.LoadZones(true)
+		if err != nil {
+			return err
+		}
+
+		ctx, cancel := context.WithTimeout(context.Background(), DNSTimeout)
+		defer cancel()
+
+		mgr, err := newDNSManager(ctx, m)
+		if err != nil {
+			return err
+		}
+
+		_, err = mgr.WriteTo(os.Stdout)
+		return err
+	},
+}
+
+var dnsAddCmd = &cobra.Command{
+	Use:    "add",
+	PreRun: setVerbosity,
+	RunE: func(_ *cobra.Command, _ []string) error {
+		return nil
+	},
+}
+
+var dnsRemoveCmd = &cobra.Command{
+	Use:    "remove",
+	PreRun: setVerbosity,
+	RunE: func(_ *cobra.Command, _ []string) error {
+		return nil
+	},
+}
+
+func init() {
+	rootCmd.AddCommand(dnsCmd)
+
+	dnsCmd.AddCommand(dnsSyncCmd)
+	dnsCmd.AddCommand(dnsWriteCmd)
+	dnsCmd.AddCommand(dnsAddCmd)
+	dnsCmd.AddCommand(dnsRemoveCmd)
+}

go.mod

@@ -13,9 +13,12 @@ require (
 	darvaza.org/slog/handlers/discard v0.4.5
 	github.com/gofrs/uuid/v5 v5.0.0
 	github.com/hack-pad/hackpadfs v0.2.1
+	github.com/libdns/cloudflare v0.1.0
+	github.com/libdns/libdns v0.2.1
 	github.com/mgechev/revive v1.3.3
 	github.com/spf13/cobra v1.7.0
 	golang.org/x/crypto v0.12.0
+	golang.org/x/net v0.14.0
 	gopkg.in/yaml.v3 v3.0.1
 )
 
@@ -40,7 +43,6 @@ require (
 	github.com/rs/zerolog v1.30.0 // indirect
 	github.com/spf13/pflag v1.0.5 // indirect
 	golang.org/x/mod v0.12.0 // indirect
-	golang.org/x/net v0.14.0 // indirect
 	golang.org/x/sys v0.12.0 // indirect
 	golang.org/x/text v0.13.0 // indirect
 	golang.org/x/tools v0.12.0 // indirect

go.sum

@@ -34,6 +34,11 @@ github.com/hack-pad/hackpadfs v0.2.1 h1:FelFhIhv26gyjujoA/yeFO+6YGlqzmc9la/6iKMI
 github.com/hack-pad/hackpadfs v0.2.1/go.mod h1:khQBuCEwGXWakkmq8ZiFUvUZz84ZkJ2KNwKvChs4OrU=
 github.com/inconshreveable/mousetrap v1.1.0 h1:wN+x4NVGpMsO7ErUn/mUI3vEoE6Jt13X2s0bqwp9tc8=
 github.com/inconshreveable/mousetrap v1.1.0/go.mod h1:vpF70FUmC8bwa3OWnCshd2FqLfsEA9PFc4w1p2J65bw=
+github.com/libdns/cloudflare v0.1.0 h1:93WkJaGaiXCe353LHEP36kAWCUw0YjFqwhkBkU2/iic=
+github.com/libdns/cloudflare v0.1.0/go.mod h1:a44IP6J1YH6nvcNl1PverfJviADgXUnsozR3a7vBKN8=
+github.com/libdns/libdns v0.2.0/go.mod h1:yQCXzk1lEZmmCPa857bnk4TsOiqYasqpyOEeSObbb40=
+github.com/libdns/libdns v0.2.1 h1:Wu59T7wSHRgtA0cfxC+n1c/e+O3upJGWytknkmFEDis=
+github.com/libdns/libdns v0.2.1/go.mod h1:yQCXzk1lEZmmCPa857bnk4TsOiqYasqpyOEeSObbb40=
 github.com/mattn/go-colorable v0.1.12/go.mod h1:u5H1YNBxpqRaxsYJYSkiCWKzEfiAb1Gb520KVy5xxl4=
 github.com/mattn/go-colorable v0.1.13 h1:fFA4WZxdEF4tXPZVKMLwD8oUnCTTo08duU7wxecdEvA=
 github.com/mattn/go-colorable v0.1.13/go.mod h1:7S9/ev0klgBDR4GtXTXX8a3vIGJpMovkB8vQcUbaXHg=

pkg/dns/dns.go

@@ -0,0 +1,31 @@
+// Package dns manages DNS entries for the cluster
+package dns
+
+import "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
+}
+
+type Zone struct {
+	Name string
+
+	Machines map[int]*Machine
+}
+
+type Machine struct {
+	ID int
+
+	Active bool
+	Addrs  []netip.Addr
+}

pkg/dns/host.go

@@ -0,0 +1,31 @@
+package dns
+
+import (
+	"context"
+	"io/fs"
+	"net/netip"
+)
+
+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:  addrs,
+	}
+
+	return nil
+}

pkg/dns/manager.go

@@ -0,0 +1,127 @@
+package dns
+
+import (
+	"errors"
+	"strings"
+	"sync"
+
+	"darvaza.org/core"
+	"darvaza.org/slog"
+	"golang.org/x/net/publicsuffix"
+
+	"git.jpi.io/amery/jpictl/pkg/cluster"
+)
+
+// Manager is a DNS Manager instance
+type Manager struct {
+	mu sync.Mutex
+
+	domain string
+	suffix string
+	zones  map[string]*Zone
+
+	p Provider
+	l slog.Logger
+}
+
+// ManagerOption configures a Manager
+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
+	}
+}
+
+// WithProvider attaches a libdns Provider to the Manager
+func WithProvider(p Provider) ManagerOption {
+	var err error
+
+	if p == nil {
+		p, err = DefaultDNSProvider()
+	}
+
+	if err != nil {
+		return newErrorManagerOption(err, "WithProvider")
+	}
+
+	return func(mgr *Manager) error {
+		mgr.p = p
+		return nil
+	}
+}
+
+// WithLogger attaches a logger to the Manager
+func WithLogger(log slog.Logger) ManagerOption {
+	if log == nil {
+		log = cluster.DefaultLogger()
+	}
+
+	return func(mgr *Manager) error {
+		mgr.l = log
+		return nil
+	}
+}
+
+func (mgr *Manager) setDefaults() error {
+	var opts []ManagerOption
+
+	if mgr.p == nil {
+		opts = append(opts, WithProvider(nil))
+	}
+
+	if mgr.l == nil {
+		opts = append(opts, WithLogger(nil))
+	}
+
+	if mgr.domain == "" || mgr.suffix == "" {
+		return errors.New("domain not specified")
+	}
+
+	mgr.zones = make(map[string]*Zone)
+
+	for _, opt := range opts {
+		if err := opt(mgr); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// WithDomain specifies where the manager operates
+func WithDomain(domain string) ManagerOption {
+	base, err := publicsuffix.EffectiveTLDPlusOne(domain)
+	if err != nil {
+		return newErrorManagerOption(err, "publicsuffix")
+	}
+
+	suffix := strings.TrimSuffix(domain, base)
+	if suffix != "" {
+		suffix = "." + suffix[:len(suffix)-1]
+	}
+
+	return func(mgr *Manager) error {
+		mgr.domain = base
+		mgr.suffix = suffix
+		return nil
+	}
+}
+
+// NewManager creates a DNS manager with the
+func NewManager(opts ...ManagerOption) (*Manager, error) {
+	mgr := new(Manager)
+
+	for _, opt := range opts {
+		if err := opt(mgr); err != nil {
+			return nil, err
+		}
+	}
+
+	if err := mgr.setDefaults(); err != nil {
+		return nil, err
+	}
+	return mgr, nil
+}

pkg/dns/provider.go

@@ -0,0 +1,36 @@
+package dns
+
+import (
+	"fmt"
+	"os"
+
+	"github.com/libdns/cloudflare"
+	"github.com/libdns/libdns"
+)
+
+const (
+	// CloudflareAPIToken is the environment variable
+	// containing the API Token
+	CloudflareAPIToken = "CLOUDFLARE_DNS_API_TOKEN"
+)
+
+// Provider manages DNS entries
+type Provider interface {
+	libdns.RecordGetter
+	libdns.RecordDeleter
+}
+
+// DefaultDNSProvider returns a cloudflare DNS provider
+// using an API Token from env [CloudflareAPIToken]
+func DefaultDNSProvider() (*cloudflare.Provider, error) {
+	s := os.Getenv(CloudflareAPIToken)
+	if s == "" {
+		return nil, fmt.Errorf("%q: %s", CloudflareAPIToken, "not found")
+	}
+
+	p := &cloudflare.Provider{
+		APIToken: s,
+	}
+
+	return p, nil
+}

pkg/dns/write.go

@@ -0,0 +1,134 @@
+package dns
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"net/netip"
+	"sort"
+	"time"
+
+	"darvaza.org/core"
+	"github.com/libdns/libdns"
+)
+
+func (mgr *Manager) WriteTo(w io.Writer) (int64, error) {
+	var buf bytes.Buffer
+
+	var zones sort.StringSlice
+
+	// sort zones
+	for name := range mgr.zones {
+		zones = append(zones, name)
+	}
+	sort.Sort(zones)
+
+	for _, name := range zones {
+		z := mgr.zones[name]
+
+		if buf.Len() > 0 {
+			_, _ = buf.WriteRune('\n')
+		}
+
+		// servers
+		err := mgr.writeZoneMachinesToBuffer(&buf, name, z)
+		if err != nil {
+			return 0, err
+		}
+	}
+
+	return buf.WriteTo(w)
+}
+
+func (mgr *Manager) writeRecordsToBuffer(buf *bytes.Buffer, records ...libdns.Record) {
+	for _, rr := range records {
+		fqdn := fmt.Sprintf("%s.%s", rr.Name, mgr.domain)
+
+		_, _ = fmt.Fprintf(buf, "%s\t%v\tIN\t%s\t%v\n",
+			fqdn, int(rr.TTL/time.Second), rr.Type, rr.Value)
+	}
+}
+
+func (mgr *Manager) writeZoneMachinesToBuffer(buf *bytes.Buffer, zone_name string, z *Zone) error {
+	// title
+	_, _ = fmt.Fprintf(buf, ";\n; %s\n;\n", zone_name)
+
+	records := mgr.genMachineRecords(z)
+	mgr.writeRecordsToBuffer(buf, records...)
+
+	// zone alias
+	_, _ = fmt.Fprintf(buf, "; %s\n", zone_name)
+	records = mgr.genAliasRecords(zone_name, true, z)
+	mgr.Sort(records)
+	mgr.writeRecordsToBuffer(buf, records...)
+
+	return nil
+}
+
+func (mgr *Manager) genMachineRecords(z *Zone) []libdns.Record {
+	var out []libdns.Record
+
+	for _, p := range z.Machines {
+		pqdn := fmt.Sprintf("%s-%v%s", z.Name, p.ID, mgr.suffix)
+
+		for _, addr := range p.Addrs {
+			out = append(out, libdns.Record{
+				Name:  pqdn,
+				Type:  core.IIf(addr.Is6(), "AAAA", "A"),
+				TTL:   time.Second,
+				Value: addr.String(),
+			})
+		}
+	}
+
+	mgr.Sort(out)
+	return out
+}
+
+func (mgr *Manager) genAliasRecords(name string, activeOnly bool, zones ...*Zone) []libdns.Record {
+	var out []libdns.Record
+
+	fqdn := fmt.Sprintf("%s%s", name, mgr.suffix)
+	for _, z := range zones {
+		for _, p := range z.Machines {
+			if p.Active || !activeOnly {
+				for _, addr := range p.Addrs {
+					out = append(out, libdns.Record{
+						Name:  fqdn,
+						Type:  core.IIf(addr.Is6(), "AAAA", "A"),
+						TTL:   time.Second,
+						Value: addr.String(),
+					})
+				}
+			}
+		}
+	}
+
+	return out
+}
+
+func (mgr *Manager) Sort(records []libdns.Record) {
+	sort.SliceStable(records, func(i, j int) bool {
+		a := &records[i]
+		b := &records[j]
+		switch {
+		case a.Name < b.Name:
+			return true
+		case a.Name > b.Name:
+			return false
+		case a.Type < b.Type:
+			return true
+		case a.Type > b.Type:
+			return false
+		case a.Type == "A" || a.Type == "AAAA":
+			var aAddr, bAddr netip.Addr
+			aAddr.UnmarshalText([]byte(a.Value))
+			bAddr.UnmarshalText([]byte(b.Value))
+			return aAddr.Less(bAddr)
+		case a.Value < b.Value:
+			return true
+		default:
+			return false
+		}
+	})
+}