Merge pull request 'dns: introduce DNS Manager and BIND config writer' (#24)

Reviewed-on: #24

.vscode/settings.json

@@ -1,9 +1,15 @@
 {
     "cSpell.words": [
+        "asciigoat",
         "ceph",
+        "cyclomatic",
         "darvaza",
         "gofrs",
         "jpictl",
+        "libdns",
+        "Lookuper",
+        "publicsuffix",
+        "Wrapf",
         "zerolog"
     ]
 }

cmd/jpictl/config.go

@@ -1,22 +1,59 @@
 package main
 
-import "git.jpi.io/amery/jpictl/pkg/zones"
+import (
+	"os"
+
+	"darvaza.org/core"
+
+	"git.jpi.io/amery/jpictl/pkg/cluster"
+)
+
+const (
+	// DefaultConfigFile is read if -f/--config-file isn't specified.
+	// If it doesn't exist, m/ will be scanned
+	DefaultConfigFile = "cloud.yaml"
+)
 
 // Config describes the repository
 type Config struct {
 	Base   string
 	Domain string
+
+	ConfigFile string
 }
 
 var cfg = &Config{
-	Base:   "./m",
-	Domain: "m.jpi.cloud",
+	Base:   "m",
+	Domain: "jpi.cloud",
 }
 
 // LoadZones loads all zones and machines in the config directory
-func (cfg *Config) LoadZones(resolve bool) (*zones.Zones, error) {
-	return zones.New(cfg.Base, cfg.Domain,
-		zones.ResolvePublicAddresses(resolve),
-		zones.WithLogger(log),
+// or file
+func (cfg *Config) LoadZones(resolve bool) (*cluster.Cluster, error) {
+	// try config file first
+	zones, err := cluster.NewFromConfig(cfg.ConfigFile,
+		cluster.ResolvePublicAddresses(resolve),
+		cluster.WithLogger(log),
+	)
+
+	switch {
+	case err == nil:
+		// file was good
+		return zones, nil
+	case !os.IsNotExist(err) || cfg.ConfigFile != DefaultConfigFile:
+		// file was bad
+		return nil, core.Wrapf(err, "NewFromConfig(%q)", cfg.ConfigFile)
+	}
+
+	// default file doesn't exist. scan instead.
+	return cluster.NewFromDirectory(cfg.Base, cfg.Domain,
+		cluster.ResolvePublicAddresses(resolve),
+		cluster.WithLogger(log),
 	)
 }
+
+func init() {
+	rootCmd.PersistentFlags().
+		StringVarP(&cfg.ConfigFile, "config-file", "f",
+			DefaultConfigFile, "config file (JSON or YAML)")
+}

cmd/jpictl/dns.go

@@ -0,0 +1,82 @@
+package main
+
+import (
+	"context"
+	"os"
+
+	"github.com/spf13/cobra"
+
+	"git.jpi.io/amery/jpictl/pkg/cluster"
+	"git.jpi.io/amery/jpictl/pkg/dns"
+)
+
+func newDNSManager(m *cluster.Cluster) (*dns.Manager, error) {
+	ctx := context.TODO()
+
+	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
+	}
+
+	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
+	}
+
+	return mgr, nil
+}
+
+// Command
+var dnsCmd = &cobra.Command{
+	Use: "dns",
+}
+
+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)
+		if err != nil {
+			return err
+		}
+
+		mgr, err := newDNSManager(m)
+		if err != nil {
+			return err
+		}
+
+		_, err = mgr.WriteTo(os.Stdout)
+		return err
+	},
+}
+
+func init() {
+	rootCmd.AddCommand(dnsCmd)
+
+	dnsCmd.AddCommand(dnsWriteCmd)
+}

cmd/jpictl/dump.go

@@ -6,7 +6,6 @@ import (
 	"io"
 	"os"
 
-	"github.com/burntSushi/toml"
 	"github.com/spf13/cobra"
 	"gopkg.in/yaml.v3"
 )
@@ -20,8 +19,8 @@ type Encoder interface {
 type Encoding int
 
 const (
-	// TOMLEncoding represents TOML encoding
-	TOMLEncoding Encoding = iota
+	// UndefinedEncoding implies the default encoding
+	UndefinedEncoding Encoding = iota
 	// JSONEncoding represents JSON encoding
 	JSONEncoding
 	// YAMLEncoding represents YAML encoding
@@ -42,18 +41,13 @@ func NewYAMLEncoder(w io.Writer) Encoder {
 	return enc
 }
 
-// NewTOMLEncoder returns a TOML [Encoder] to work on the given [io.Writer]
-func NewTOMLEncoder(w io.Writer) Encoder {
-	enc := toml.NewEncoder(w)
-	return enc
-}
-
 const encoding = YAMLEncoding
 
 // Command
 var dumpCmd = &cobra.Command{
-	Use:   "dump",
-	Short: "generates a text representation of the config",
+	Use:    "dump",
+	Short:  "generates a text representation of the config",
+	PreRun: setVerbosity,
 	RunE: func(_ *cobra.Command, _ []string) error {
 		var buf bytes.Buffer
 		var enc Encoder
@@ -66,10 +60,8 @@ var dumpCmd = &cobra.Command{
 		switch encoding {
 		case JSONEncoding:
 			enc = NewJSONEncoder(&buf)
-		case YAMLEncoding:
-			enc = NewYAMLEncoder(&buf)
 		default:
-			enc = NewTOMLEncoder(&buf)
+			enc = NewYAMLEncoder(&buf)
 		}
 
 		if err = enc.Encode(m); err != nil {

cmd/jpictl/env.go

@@ -8,8 +8,9 @@ import (
 
 // Command
 var envCmd = &cobra.Command{
-	Use:   "env",
-	Short: "generates environment variables for shell scripts",
+	Use:    "env",
+	Short:  "generates environment variables for shell scripts",
+	PreRun: setVerbosity,
 	RunE: func(_ *cobra.Command, _ []string) error {
 		m, err := cfg.LoadZones(false)
 		if err != nil {

cmd/jpictl/gateway.go

@@ -7,8 +7,9 @@ import (
 	"strconv"
 	"strings"
 
-	"git.jpi.io/amery/jpictl/pkg/zones"
 	"github.com/spf13/cobra"
+
+	"git.jpi.io/amery/jpictl/pkg/cluster"
 )
 
 // Command
@@ -19,8 +20,9 @@ var gatewayCmd = &cobra.Command{
 
 // gateway set
 var gatewaySetCmd = &cobra.Command{
-	Use:   "set",
-	Short: "gateway set sets machines as gateways",
+	Use:    "set",
+	Short:  "gateway set sets machines as gateways",
+	PreRun: setVerbosity,
 	RunE: func(_ *cobra.Command, args []string) error {
 		m, err := cfg.LoadZones(false)
 		if err != nil {
@@ -37,9 +39,9 @@ var gatewaySetCmd = &cobra.Command{
 	},
 }
 
-func gatewaySet(zi zones.ZoneIterator, gw string) error {
+func gatewaySet(zi cluster.ZoneIterator, gw string) error {
 	var err error
-	zi.ForEachZone(func(z *zones.Zone) bool {
+	zi.ForEachZone(func(z *cluster.Zone) bool {
 		for _, m := range z.Machines {
 			if m.Name == gw {
 				z.SetGateway(m.ID, true)
@@ -73,9 +75,9 @@ var gatewayUnsetCmd = &cobra.Command{
 	},
 }
 
-func gatewayUnset(zi zones.ZoneIterator, ngw string) error {
+func gatewayUnset(zi cluster.ZoneIterator, ngw string) error {
 	var err error
-	zi.ForEachZone(func(z *zones.Zone) bool {
+	zi.ForEachZone(func(z *cluster.Zone) bool {
 		for _, m := range z.Machines {
 			if m.Name == ngw && m.IsGateway() {
 				z.SetGateway(m.ID, false)
@@ -114,10 +116,10 @@ var gatewayListCmd = &cobra.Command{
 	},
 }
 
-func gatewayListAll(zi zones.ZoneIterator) error {
+func gatewayListAll(zi cluster.ZoneIterator) error {
 	var b bytes.Buffer
 	var err error
-	zi.ForEachZone(func(z *zones.Zone) bool {
+	zi.ForEachZone(func(z *cluster.Zone) bool {
 		b.WriteString(z.Name + ":")
 		var sIDs []string
 		ids, num := z.GatewayIDs()
@@ -136,10 +138,10 @@ func gatewayListAll(zi zones.ZoneIterator) error {
 	return err
 }
 
-func gatewayList(zi zones.ZoneIterator, m string) error {
+func gatewayList(zi cluster.ZoneIterator, m string) error {
 	var b bytes.Buffer
 	var err error
-	zi.ForEachZone(func(z *zones.Zone) bool {
+	zi.ForEachZone(func(z *cluster.Zone) bool {
 		if z.Name == m {
 			b.WriteString(z.Name + ":")
 			ids, num := z.GatewayIDs()

cmd/jpictl/log.go

@@ -3,15 +3,9 @@ package main
 import (
 	"fmt"
 
-	"darvaza.org/sidecar/pkg/logger/zerolog"
 	"darvaza.org/slog"
 )
 
-// TODO: make log level configurable via flags
-var (
-	log = zerolog.New(nil, slog.Debug)
-)
-
 // fatal is a convenience wrapper for slog.Logger.Fatal().Print()
 func fatal(err error, msg string, args ...any) {
 	l := log.Fatal()

cmd/jpictl/main.go

@@ -2,6 +2,8 @@
 package main
 
 import (
+	"darvaza.org/sidecar/pkg/logger/zerolog"
+	"darvaza.org/slog"
 	"github.com/spf13/cobra"
 )
 
@@ -10,13 +12,30 @@ const (
 	CmdName = "jpictl"
 )
 
-var rootCmd = &cobra.Command{
-	Use:   CmdName,
-	Short: "control tool for jpi.cloud",
-}
+var (
+	log       = zerolog.New(nil, slog.Error)
+	verbosity int
+	rootCmd   = &cobra.Command{
+		Use:   CmdName,
+		Short: "control tool for jpi.cloud",
+	}
+)
 
 func main() {
 	if err := rootCmd.Execute(); err != nil {
 		fatal(err, "")
 	}
 }
+
+func init() {
+	rootCmd.PersistentFlags().CountVarP(&verbosity, "verbosity", "v",
+		"increase the verbosity level to Warn, Info or Debug")
+}
+
+func setVerbosity(_ *cobra.Command, _ []string) {
+	desired := int8(slog.Error) + int8(verbosity)
+	if desired > 6 {
+		desired = 6
+	}
+	log = zerolog.New(nil, slog.LogLevel(desired))
+}

cmd/jpictl/write.go

@@ -6,8 +6,9 @@ import (
 
 // Command
 var writeCmd = &cobra.Command{
-	Use:   "write",
-	Short: "rewrites all config files",
+	Use:    "write",
+	Short:  "rewrites all config files",
+	PreRun: setVerbosity,
 	RunE: func(_ *cobra.Command, _ []string) error {
 		m, err := cfg.LoadZones(false)
 		if err != nil {

go.mod

@@ -9,12 +9,14 @@ require (
 	darvaza.org/sidecar v0.0.2
 	darvaza.org/slog v0.5.3
 	darvaza.org/slog/handlers/discard v0.4.5
-	github.com/burntSushi/toml v0.3.1
 	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/gcfg.v1 v1.2.3
 	gopkg.in/yaml.v3 v3.0.1
 )
@@ -40,7 +42,6 @@ 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

@@ -18,8 +18,6 @@ darvaza.org/slog/handlers/zerolog v0.4.5 h1:W4cgGORx4wImr+RL96CWSQGTdkZzKX6YHXPS
 darvaza.org/slog/handlers/zerolog v0.4.5/go.mod h1:mCoh/mIl8Nsa6Yu1Um7d7cos6RuEJzgaTXaX5LDRUao=
 github.com/BurntSushi/toml v1.3.2 h1:o7IhLm0Msx3BaB+n3Ag7L8EVlByGnpq14C4YWiu/gL8=
 github.com/BurntSushi/toml v1.3.2/go.mod h1:CxXYINrC8qIiEnFrOxCa7Jy5BFHlXnUU2pbicEuybxQ=
-github.com/burntSushi/toml v0.3.1 h1:Hu1cOEC2qtKULZJCzym5tyA35bZr3HREuolgiAzMlhY=
-github.com/burntSushi/toml v0.3.1/go.mod h1:sGTquCpRYr9McuHdv0m6YKIhx8DJGJa4t04/Y9pfSio=
 github.com/chavacava/garif v0.1.0 h1:2JHa3hbYf5D9dsgseMKAmc/MZ109otzgNFk5s87H9Pc=
 github.com/chavacava/garif v0.1.0/go.mod h1:XMyYCkEL58DF0oyW4qDjjnPWONs2HBqYKI+UIPD+Gww=
 github.com/coreos/go-systemd/v22 v22.5.0/go.mod h1:Y58oyj3AT4RCenI/lSvhwexgC+NSVTIJ3seZv2GcEnc=
@@ -38,6 +36,11 @@ 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/cluster/ceph.go

@@ -1,4 +1,4 @@
-package zones
+package cluster
 
 import (
 	"bytes"
@@ -12,7 +12,7 @@ import (
 )
 
 // GetCephFSID returns our Ceph's FSID
-func (m *Zones) GetCephFSID() (uuid.UUID, error) {
+func (m *Cluster) GetCephFSID() (uuid.UUID, error) {
 	if core.IsZero(m.CephFSID) {
 		// generate one
 		v, err := uuid.NewV4()
@@ -25,7 +25,7 @@ func (m *Zones) GetCephFSID() (uuid.UUID, error) {
 }
 
 // GetCephConfig reads the ceph.conf file
-func (m *Zones) GetCephConfig() (*ceph.Config, error) {
+func (m *Cluster) GetCephConfig() (*ceph.Config, error) {
 	data, err := m.ReadFile("ceph.conf")
 	if err != nil {
 		return nil, err
@@ -36,7 +36,7 @@ func (m *Zones) GetCephConfig() (*ceph.Config, error) {
 }
 
 // WriteCephConfig writes the ceph.conf file
-func (m *Zones) WriteCephConfig(cfg *ceph.Config) error {
+func (m *Cluster) WriteCephConfig(cfg *ceph.Config) error {
 	f, err := m.CreateTruncFile("ceph.conf")
 	if err != nil {
 		return err
@@ -48,7 +48,7 @@ func (m *Zones) WriteCephConfig(cfg *ceph.Config) error {
 }
 
 // GenCephConfig prepares a ceph.Config using the cluster information
-func (m *Zones) GenCephConfig() (*ceph.Config, error) {
+func (m *Cluster) GenCephConfig() (*ceph.Config, error) {
 	fsid, err := m.GetCephFSID()
 	if err != nil {
 		return nil, err

pkg/cluster/ceph_scan.go

@@ -0,0 +1,107 @@
+package cluster
+
+import (
+	"os"
+
+	"darvaza.org/slog"
+	"git.jpi.io/amery/jpictl/pkg/ceph"
+)
+
+type cephScanTODO struct {
+	names map[string]bool
+	addrs map[string]bool
+}
+
+func (todo *cephScanTODO) checkMachine(p *Machine) bool {
+	// on ceph all addresses are ring1
+	ring1, _ := RingOneAddress(p.Zone(), p.ID)
+	addr := ring1.String()
+
+	if _, found := todo.names[p.Name]; found {
+		// found on the TODO by name
+		todo.names[p.Name] = true
+		todo.addrs[addr] = true
+		return true
+	}
+
+	if _, found := todo.addrs[addr]; found {
+		// found on the TODO by address
+		todo.names[p.Name] = true
+		todo.addrs[addr] = true
+		return true
+	}
+
+	return false
+}
+
+func (todo *cephScanTODO) LogMissing(log slog.Logger) {
+	for name, found := range todo.names {
+		if !found {
+			log.Warn().
+				WithField("subsystem", "ceph").
+				WithField("monitor", name).
+				Print("unknown monitor")
+		}
+	}
+
+	for addr, found := range todo.addrs {
+		if !found {
+			log.Warn().
+				WithField("subsystem", "ceph").
+				WithField("monitor", addr).
+				Print("unknown monitor")
+		}
+	}
+}
+
+func newCephScanTODO(cfg *ceph.Config) *cephScanTODO {
+	todo := &cephScanTODO{
+		names: make(map[string]bool),
+		addrs: make(map[string]bool),
+	}
+
+	for _, name := range cfg.Global.Monitors {
+		todo.names[name] = false
+	}
+
+	for _, addr := range cfg.Global.MonitorsAddr {
+		todo.addrs[addr.String()] = false
+	}
+
+	return todo
+}
+
+func (m *Cluster) scanCephMonitors(opts *ScanOptions) error {
+	cfg, err := m.GetCephConfig()
+	switch {
+	case os.IsNotExist(err):
+		err = nil
+	case err != nil:
+		return err
+	}
+
+	if cfg != nil {
+		// store FSID
+		m.CephFSID = cfg.Global.FSID
+
+		// flag monitors based on config
+		todo := newCephScanTODO(cfg)
+		m.ForEachMachine(func(p *Machine) bool {
+			p.CephMonitor = todo.checkMachine(p)
+			return false
+		})
+
+		todo.LogMissing(m.log)
+	}
+
+	return m.initCephMonitors(opts)
+}
+
+func (m *Cluster) initCephMonitors(_ *ScanOptions) error {
+	// make sure every zone has one
+	m.ForEachZone(func(z *Zone) bool {
+		_ = z.GetCephMonitors()
+		return false
+	})
+	return nil
+}

pkg/cluster/cluster.go

@@ -0,0 +1,78 @@
+// Package cluster contains information about the cluster
+package cluster
+
+import (
+	"io/fs"
+
+	"darvaza.org/resolver"
+	"darvaza.org/slog"
+	"github.com/gofrs/uuid/v5"
+)
+
+var (
+	_ MachineIterator = (*Cluster)(nil)
+	_ ZoneIterator    = (*Cluster)(nil)
+)
+
+// revive:disable:line-length-limit
+
+// Cluster represents all zones in a cluster
+type Cluster struct {
+	dir      fs.FS
+	log      slog.Logger
+	resolver resolver.Resolver
+
+	BaseDir string `json:"dir,omitempty"    yaml:"dir,omitempty"`
+	Name    string `json:"name,omitempty"   yaml:"name,omitempty"`
+	Domain  string `json:"domain,omitempty" yaml:"domain,omitempty"`
+
+	CephFSID uuid.UUID `json:"ceph_fsid,omitempty" yaml:"ceph_fsid,omitempty"`
+	Regions  []Region  `json:",omitempty"          yaml:",omitempty"`
+	Zones    []*Zone   `json:",omitempty"          yaml:",omitempty"`
+}
+
+// revive:enable:line-length-limit
+
+// ForEachMachine calls a function for each Machine in the cluster
+// until instructed to terminate the loop
+func (m *Cluster) ForEachMachine(fn func(*Machine) bool) {
+	m.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 cluster
+// until instructed to terminate the loop
+func (m *Cluster) ForEachZone(fn func(*Zone) bool) {
+	for _, p := range m.Zones {
+		if fn(p) {
+			// terminate
+			return
+		}
+	}
+}
+
+// GetMachineByName looks for a machine with the specified
+// name on any zone
+func (m *Cluster) GetMachineByName(name string) (*Machine, bool) {
+	var out *Machine
+
+	if name != "" {
+		m.ForEachMachine(func(p *Machine) bool {
+			if p.Name == name {
+				out = p
+			}
+
+			return out != nil
+		})
+	}
+
+	return out, out != nil
+}

pkg/cluster/cluster_file.go

@@ -1,4 +1,4 @@
-package zones
+package cluster
 
 import (
 	"fmt"
@@ -9,7 +9,7 @@ import (
 )
 
 // OpenFile opens a file on the cluster's config directory with the specified flags
-func (m *Zones) OpenFile(name string, flags int, args ...any) (fs.File, error) {
+func (m *Cluster) OpenFile(name string, flags int, args ...any) (fs.File, error) {
 	if len(args) > 0 {
 		name = fmt.Sprintf(name, args...)
 	}
@@ -18,16 +18,16 @@ func (m *Zones) OpenFile(name string, flags int, args ...any) (fs.File, error) {
 }
 
 // CreateTruncFile creates or truncates a file on the cluster's config directory
-func (m *Zones) CreateTruncFile(name string, args ...any) (io.WriteCloser, error) {
+func (m *Cluster) CreateTruncFile(name string, args ...any) (io.WriteCloser, error) {
 	return m.openWriter(name, os.O_CREATE|os.O_TRUNC, args...)
 }
 
 // CreateFile creates a file on the cluster's config directory
-func (m *Zones) CreateFile(name string, args ...any) (io.WriteCloser, error) {
+func (m *Cluster) CreateFile(name string, args ...any) (io.WriteCloser, error) {
 	return m.openWriter(name, os.O_CREATE, args...)
 }
 
-func (m *Zones) openWriter(name string, flags int, args ...any) (io.WriteCloser, error) {
+func (m *Cluster) openWriter(name string, flags int, args ...any) (io.WriteCloser, error) {
 	f, err := m.OpenFile(name, os.O_WRONLY|flags, args...)
 	if err != nil {
 		return nil, err
@@ -37,7 +37,7 @@ func (m *Zones) openWriter(name string, flags int, args ...any) (io.WriteCloser,
 }
 
 // ReadFile reads a file from the cluster's config directory
-func (m *Zones) ReadFile(name string, args ...any) ([]byte, error) {
+func (m *Cluster) ReadFile(name string, args ...any) ([]byte, error) {
 	if len(args) > 0 {
 		name = fmt.Sprintf(name, args...)
 	}

pkg/cluster/cluster_fs.go

@@ -0,0 +1,25 @@
+package cluster
+
+import (
+	"io/fs"
+	"path/filepath"
+
+	"github.com/hack-pad/hackpadfs/os"
+)
+
+// DirFS returns a file system (an [fs.FS]) for the tree
+// of files rooted at the directory dir.
+func DirFS(dir string) (fs.FS, error) {
+	dir = filepath.Clean(dir)
+	fullPath, err := filepath.Abs(dir)
+	if err != nil {
+		return nil, err
+	}
+
+	sub, err := os.NewFS().Sub(fullPath[1:])
+	if err != nil {
+		return nil, err
+	}
+
+	return sub, nil
+}

pkg/cluster/cluster_import.go

@@ -0,0 +1,139 @@
+package cluster
+
+import (
+	"encoding/json"
+	"fmt"
+	"os"
+
+	"gopkg.in/yaml.v3"
+)
+
+func (m *Cluster) init(opts *ScanOptions) error {
+	for _, fn := range []func(*ScanOptions) error{
+		m.initZones,
+		m.scanZoneIDs,
+		m.scanSort,
+		m.scanGateways,
+		m.initCephMonitors,
+		m.initRegions,
+	} {
+		if err := fn(opts); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func (m *Cluster) initZones(opts *ScanOptions) error {
+	var err error
+
+	sub, err := DirFS(m.BaseDir)
+	if err != nil {
+		return err
+	}
+
+	m.dir = sub
+
+	m.ForEachZone(func(z *Zone) bool {
+		err = m.initZone(z, opts)
+		return err != nil
+	})
+
+	return err
+}
+
+func (m *Cluster) initZone(z *Zone, _ *ScanOptions) error {
+	var hasMissing bool
+	var lastMachineID int
+
+	z.zones = m
+	z.logger = m
+
+	z.ForEachMachine(func(p *Machine) bool {
+		p.zone = z
+		p.logger = z
+
+		switch {
+		case p.ID == 0:
+			hasMissing = true
+		case p.ID > lastMachineID:
+			lastMachineID = z.ID
+		}
+
+		return false
+	})
+
+	if hasMissing {
+		next := lastMachineID + 1
+
+		z.ForEachMachine(func(p *Machine) bool {
+			if p.ID == 0 {
+				p.ID, next = next, next+1
+			}
+
+			return false
+		})
+	}
+
+	z.ForEachMachine(func(p *Machine) bool {
+		p.Name = fmt.Sprintf("%s-%v", z.Name, p.ID)
+		return false
+	})
+
+	return nil
+}
+
+func decodeConfigData(data []byte) (out *Cluster, err error) {
+	// try JSON first
+	out = new(Cluster)
+	err = json.Unmarshal(data, out)
+	if err == nil {
+		// good json
+		return out, nil
+	} else if _, ok := err.(*json.SyntaxError); !ok {
+		// bad json
+		return nil, err
+	}
+
+	out = new(Cluster)
+	err = yaml.Unmarshal(data, out)
+	if err != nil {
+		// bad yaml too
+		return nil, err
+	}
+
+	// good yaml
+	return out, nil
+}
+
+// NewFromConfig loads the cluster data from the given file
+func NewFromConfig(filename string, opts ...ScanOption) (*Cluster, error) {
+	var scanOptions ScanOptions
+
+	data, err := os.ReadFile(filename)
+	if err != nil {
+		return nil, err
+	}
+
+	m, err := decodeConfigData(data)
+	if err != nil {
+		return nil, err
+	}
+
+	for _, opt := range opts {
+		if err = opt(m, &scanOptions); err != nil {
+			return nil, err
+		}
+	}
+
+	if err = m.setScanDefaults(&scanOptions); err != nil {
+		return nil, err
+	}
+
+	if err := m.init(&scanOptions); err != nil {
+		return nil, err
+	}
+
+	return m, nil
+}

pkg/cluster/cluster_scan.go

@@ -1,4 +1,4 @@
-package zones
+package cluster
 
 import (
 	"io/fs"
@@ -7,7 +7,7 @@ import (
 	"darvaza.org/core"
 )
 
-func (m *Zones) scan(opts *ScanOptions) error {
+func (m *Cluster) scan(opts *ScanOptions) error {
 	for _, fn := range []func(*ScanOptions) error{
 		m.scanDirectory,
 		m.scanMachines,
@@ -24,7 +24,7 @@ func (m *Zones) scan(opts *ScanOptions) error {
 	return nil
 }
 
-func (m *Zones) scanDirectory(_ *ScanOptions) error {
+func (m *Cluster) scanDirectory(_ *ScanOptions) error {
 	// each directory is a zone
 	entries, err := fs.ReadDir(m.dir, ".")
 	if err != nil {
@@ -37,7 +37,11 @@ func (m *Zones) scanDirectory(_ *ScanOptions) error {
 			switch {
 			case err != nil:
 				return core.Wrap(err, e.Name())
-			case z.Machines.Len() > 0:
+			case z.Machines.Len() == 0:
+				z.warn(nil).
+					WithField("zone", z.Name).
+					Print("empty")
+			default:
 				m.Zones = append(m.Zones, z)
 			}
 		}
@@ -46,20 +50,24 @@ func (m *Zones) scanDirectory(_ *ScanOptions) error {
 	return nil
 }
 
-func (m *Zones) newZone(name string) (*Zone, error) {
+func (m *Cluster) newZone(name string) (*Zone, error) {
 	z := &Zone{
 		zones:  m,
 		logger: m,
 		Name:   name,
 	}
 
+	z.debug().
+		WithField("zone", z.Name).
+		Print("found")
+
 	if err := z.scan(); err != nil {
 		return nil, err
 	}
 	return z, nil
 }
 
-func (m *Zones) scanMachines(opts *ScanOptions) error {
+func (m *Cluster) scanMachines(opts *ScanOptions) error {
 	var err error
 	m.ForEachMachine(func(p *Machine) bool {
 		err = p.scan(opts)
@@ -68,7 +76,7 @@ func (m *Zones) scanMachines(opts *ScanOptions) error {
 	return err
 }
 
-func (m *Zones) scanZoneIDs(_ *ScanOptions) error {
+func (m *Cluster) scanZoneIDs(_ *ScanOptions) error {
 	var hasMissing bool
 	var lastZoneID int
 
@@ -98,7 +106,7 @@ func (m *Zones) scanZoneIDs(_ *ScanOptions) error {
 	return nil
 }
 
-func (m *Zones) scanSort(_ *ScanOptions) error {
+func (m *Cluster) scanSort(_ *ScanOptions) error {
 	sort.SliceStable(m.Zones, func(i, j int) bool {
 		id1 := m.Zones[i].ID
 		id2 := m.Zones[j].ID
@@ -124,7 +132,7 @@ func (m *Zones) scanSort(_ *ScanOptions) error {
 	return nil
 }
 
-func (m *Zones) scanGateways(_ *ScanOptions) error {
+func (m *Cluster) scanGateways(_ *ScanOptions) error {
 	var err error
 
 	m.ForEachZone(func(z *Zone) bool {
@@ -149,7 +157,17 @@ func (z *Zone) scan() error {
 				Name:   e.Name(),
 			}
 
+			m.debug().
+				WithField("node", m.Name).
+				WithField("zone", z.Name).
+				Print("found")
+
 			if err := m.init(); err != nil {
+				m.error(err).
+					WithField("node", m.Name).
+					WithField("zone", z.Name).
+					Print()
+
 				return err
 			}
 

pkg/cluster/cluster_scan_options.go

@@ -1,4 +1,4 @@
-package zones
+package cluster
 
 import (
 	"io/fs"
@@ -6,12 +6,10 @@ import (
 
 	"darvaza.org/resolver"
 	"darvaza.org/slog"
-	"darvaza.org/slog/handlers/discard"
-	"github.com/hack-pad/hackpadfs/os"
 )
 
 // A ScanOption pre-configures the Zones before scanning
-type ScanOption func(*Zones, *ScanOptions) error
+type ScanOption func(*Cluster, *ScanOptions) error
 
 // ScanOptions contains flags used by the initial scan
 type ScanOptions struct {
@@ -29,7 +27,7 @@ type ScanOptions struct {
 // the DNS resolver to get PublicAddresses of nodes.
 // Default is true
 func ResolvePublicAddresses(resolve bool) ScanOption {
-	return func(m *Zones, opt *ScanOptions) error {
+	return func(m *Cluster, opt *ScanOptions) error {
 		opt.DontResolvePublicAddresses = !resolve
 		return nil
 	}
@@ -38,7 +36,7 @@ func ResolvePublicAddresses(resolve bool) ScanOption {
 // WithLookuper specifies what resolver.Lookuper to use to
 // find public addresses
 func WithLookuper(h resolver.Lookuper) ScanOption {
-	return func(m *Zones, opt *ScanOptions) error {
+	return func(m *Cluster, opt *ScanOptions) error {
 		if h == nil {
 			return fs.ErrInvalid
 		}
@@ -51,7 +49,7 @@ func WithLookuper(h resolver.Lookuper) ScanOption {
 // public addresses. if nil is passed, the [net.Resolver] will be used.
 // The default is using Cloudflare's 1.1.1.1.
 func WithResolver(h resolver.Resolver) ScanOption {
-	return func(m *Zones, opt *ScanOptions) error {
+	return func(m *Cluster, opt *ScanOptions) error {
 		if h == nil {
 			h = resolver.SystemResolver(true)
 		}
@@ -63,9 +61,9 @@ func WithResolver(h resolver.Resolver) ScanOption {
 
 // WithLogger specifies what to use for logging
 func WithLogger(log slog.Logger) ScanOption {
-	return func(m *Zones, opt *ScanOptions) error {
+	return func(m *Cluster, opt *ScanOptions) error {
 		if log == nil {
-			log = discard.New()
+			log = DefaultLogger()
 		}
 
 		opt.Logger = log
@@ -74,9 +72,9 @@ func WithLogger(log slog.Logger) ScanOption {
 	}
 }
 
-func (m *Zones) setDefaults(opt *ScanOptions) error {
+func (m *Cluster) setScanDefaults(opt *ScanOptions) error {
 	if m.resolver == nil {
-		h := resolver.NewCloudflareLookuper()
+		h := DefaultLookuper()
 
 		if err := WithLookuper(h)(m, opt); err != nil {
 			return err
@@ -92,43 +90,41 @@ func (m *Zones) setDefaults(opt *ScanOptions) error {
 	return nil
 }
 
-// NewFS builds a [Zones] tree using the given directory
-func NewFS(dir fs.FS, domain string, opts ...ScanOption) (*Zones, error) {
+// NewFromDirectory builds a [Cluster] tree using the given directory
+func NewFromDirectory(dir, domain string, opts ...ScanOption) (*Cluster, error) {
 	var scanOptions ScanOptions
 
-	z := &Zones{
-		dir:    dir,
-		domain: domain,
+	dir = filepath.Clean(dir)
+	fullPath, err := filepath.Abs(dir)
+	if err != nil {
+		return nil, err
+	}
+
+	sub, err := DirFS(dir)
+	if err != nil {
+		return nil, err
+	}
+
+	m := &Cluster{
+		dir:     sub,
+		BaseDir: dir,
+		Name:    filepath.Base(fullPath),
+		Domain:  domain,
 	}
 
 	for _, opt := range opts {
-		if err := opt(z, &scanOptions); err != nil {
+		if err := opt(m, &scanOptions); err != nil {
 			return nil, err
 		}
 	}
 
-	if err := z.setDefaults(&scanOptions); err != nil {
+	if err := m.setScanDefaults(&scanOptions); err != nil {
 		return nil, err
 	}
 
-	if err := z.scan(&scanOptions); err != nil {
+	if err := m.scan(&scanOptions); err != nil {
 		return nil, err
 	}
 
-	return z, nil
-}
-
-// New builds a [Zones] tree using the given directory
-func New(dir, domain string, opts ...ScanOption) (*Zones, error) {
-	dir, err := filepath.Abs(dir)
-	if err != nil {
-		return nil, err
-	}
-
-	base, err := os.NewFS().Sub(dir[1:])
-	if err != nil {
-		return nil, err
-	}
-
-	return NewFS(base, domain, opts...)
+	return m, nil
 }

pkg/cluster/defaults.go

@@ -0,0 +1,17 @@
+package cluster
+
+import (
+	"darvaza.org/resolver"
+	"darvaza.org/slog"
+	"darvaza.org/slog/handlers/discard"
+)
+
+// DefaultLogger returns a logger that doesn't log anything
+func DefaultLogger() slog.Logger {
+	return discard.New()
+}
+
+// DefaultLookuper returns a [resolver.Lookuper] using Cloudflare's 1.1.1.1
+func DefaultLookuper() resolver.Lookuper {
+	return resolver.NewCloudflareLookuper()
+}

pkg/cluster/env.go

@@ -1,4 +1,4 @@
-package zones
+package cluster
 
 import (
 	"bytes"
@@ -16,7 +16,7 @@ type Env struct {
 }
 
 // Env returns a shell environment factory
-func (m *Zones) Env(export bool) (*Env, error) {
+func (m *Cluster) Env(export bool) (*Env, error) {
 	fsid, err := m.GetCephFSID()
 	if err != nil {
 		return nil, err

pkg/cluster/errors.go

@@ -1,4 +1,4 @@
-package zones
+package cluster
 
 import "errors"
 

pkg/cluster/hosts.go

@@ -0,0 +1,128 @@
+package cluster
+
+import (
+	"bytes"
+	"fmt"
+	"strings"
+	"text/template"
+)
+
+type hostsFile struct {
+	Ring0 []hostsEntry
+	Ring1 []hostsEntry
+}
+
+type hostsEntry struct {
+	Addr  string
+	Names []string
+}
+
+var hostsTemplate = template.Must(template.New("hosts").Funcs(template.FuncMap{
+	"StringsJoin": strings.Join,
+}).Parse(`127.0.0.1 localhost
+
+# The following lines are desirable for IPv6 capable hosts
+::1     ip6-localhost ip6-loopback
+fe00::0 ip6-localnet
+ff00::0 ip6-mcastprefix
+ff02::1 ip6-allnodes
+ff02::2 ip6-allrouters
+ff02::3 ip6-allhosts
+
+{{range .Ring1 -}}
+{{.Addr}}  {{StringsJoin .Names " "}}
+{{end}}
+{{range .Ring0 -}}
+{{.Addr}}  {{StringsJoin .Names " "}}
+{{end -}}
+`))
+
+// WriteHosts rewrites all hosts files on the tree
+func (m *Cluster) WriteHosts() error {
+	var err error
+
+	m.ForEachZone(func(z *Zone) bool {
+		err = z.WriteHosts()
+		return err != nil
+	})
+
+	return err
+}
+
+// WriteHosts rewrites all hosts files in the zone
+func (z *Zone) WriteHosts() error {
+	var err error
+
+	s := z.Hosts()
+	z.ForEachMachine(func(p *Machine) bool {
+		err = p.WriteStringFile(s, "hosts")
+		return err != nil
+	})
+
+	return err
+}
+
+// WriteHosts rewrites the hosts file
+func (p *Machine) WriteHosts() error {
+	s := p.zone.Hosts()
+	return p.WriteStringFile(s, "hosts")
+}
+
+func (z *Zone) genHosts(out *hostsFile, p *Machine) {
+	var names []string
+
+	ip, _ := RingOneAddress(p.zone.ID, p.ID)
+	names = append(names, p.Name)
+
+	if p.CephMonitor {
+		names = append(names, fmt.Sprintf("%s-%s", p.zone.Name, "ceph"))
+		names = append(names, fmt.Sprintf("%s-%s", p.zone.Name, "k3s"))
+
+		if z.ID == p.zone.ID {
+			names = append(names, "ceph")
+			names = append(names, "k3s")
+		}
+	}
+
+	entry := hostsEntry{
+		Addr:  ip.String(),
+		Names: names,
+	}
+
+	out.Ring1 = append(out.Ring1, entry)
+
+	if p.IsGateway() {
+		var s string
+
+		ip, _ = RingZeroAddress(p.zone.ID, p.ID)
+		s = fmt.Sprintf("%s-%v", p.Name, 0)
+
+		entry = hostsEntry{
+			Addr:  ip.String(),
+			Names: []string{s},
+		}
+
+		out.Ring0 = append(out.Ring0, entry)
+	}
+}
+
+// Hosts renders the /etc/hosts to be used on this zone
+func (z *Zone) Hosts() string {
+	var buf bytes.Buffer
+	var out hostsFile
+
+	z.zones.ForEachZone(func(z2 *Zone) bool {
+		z2.ForEachMachine(func(p *Machine) bool {
+			z.genHosts(&out, p)
+
+			return false
+		})
+		return false
+	})
+
+	if err := hostsTemplate.Execute(&buf, &out); err != nil {
+		panic(err)
+	}
+
+	return buf.String()
+}

pkg/cluster/log.go

@@ -1,4 +1,4 @@
-package zones
+package cluster
 
 import "darvaza.org/slog"
 
@@ -13,26 +13,26 @@ type logger interface {
 }
 
 var (
-	_ logger = (*Zones)(nil)
+	_ logger = (*Cluster)(nil)
 )
 
-func (z *Zones) withDebug() (slog.Logger, bool) {
+func (z *Cluster) withDebug() (slog.Logger, bool) {
 	return z.debug().WithEnabled()
 }
 
-func (z *Zones) withInfo() (slog.Logger, bool) {
+func (z *Cluster) withInfo() (slog.Logger, bool) {
 	return z.debug().WithEnabled()
 }
 
-func (z *Zones) debug() slog.Logger {
+func (z *Cluster) debug() slog.Logger {
 	return z.log.Debug()
 }
 
-func (z *Zones) info() slog.Logger {
+func (z *Cluster) info() slog.Logger {
 	return z.log.Info()
 }
 
-func (z *Zones) warn(err error) slog.Logger {
+func (z *Cluster) warn(err error) slog.Logger {
 	l := z.log.Warn()
 	if err != nil {
 		l = l.WithField(slog.ErrorFieldName, err)
@@ -40,7 +40,7 @@ func (z *Zones) warn(err error) slog.Logger {
 	return l
 }
 
-func (z *Zones) error(err error) slog.Logger {
+func (z *Cluster) error(err error) slog.Logger {
 	l := z.log.Error()
 	if err != nil {
 		l = l.WithField(slog.ErrorFieldName, err)

pkg/cluster/machine.go

@@ -1,4 +1,4 @@
-package zones
+package cluster
 
 import (
 	"net/netip"
@@ -10,15 +10,14 @@ import (
 // A Machine is a machine on a Zone
 type Machine struct {
 	zone   *Zone
-	logger `toml:"-" json:"-" yaml:"-"`
+	logger `json:"-" yaml:"-"`
 
-	ID   int    `toml:"id"`
-	Name string `toml:"-" json:"-" yaml:"-"`
+	ID   int
+	Name string `json:"-" yaml:"-"`
 
-	PublicAddresses []netip.Addr `toml:"public,omitempty" json:"public,omitempty" yaml:"public,omitempty"`
-	Rings           []*RingInfo  `toml:"rings,omitempty"  json:"rings,omitempty"  yaml:"rings,omitempty"`
-
-	CephMonitor bool `toml:"ceph_monitor,omitempty" json:"ceph_monitor,omitempty" yaml:"ceph_monitor,omitempty"`
+	CephMonitor     bool         `json:"ceph_monitor,omitempty" yaml:"ceph_monitor,omitempty"`
+	PublicAddresses []netip.Addr `json:"public,omitempty"       yaml:"public,omitempty"`
+	Rings           []*RingInfo  `json:"rings,omitempty"        yaml:"rings,omitempty"`
 }
 
 // revive:enable:line-length-limit
@@ -29,16 +28,19 @@ func (m *Machine) String() string {
 
 // FullName returns the Name of the machine including domain name
 func (m *Machine) FullName() string {
-	if domain := m.zone.zones.domain; domain != "" {
-		var s = []string{
-			m.Name,
-			domain,
-		}
+	var name []string
 
-		return strings.Join(s, ".")
+	for _, s := range []string{
+		m.Name,
+		m.zone.zones.Name,
+		m.zone.zones.Domain,
+	} {
+		if s != "" {
+			name = append(name, s)
+		}
 	}
 
-	return m.Name
+	return strings.Join(name, ".")
 }
 
 // IsGateway tells if the Machine is a ring0 gateway

pkg/cluster/machine_file.go

@@ -1,4 +1,4 @@
-package zones
+package cluster
 
 import (
 	"bytes"

pkg/cluster/machine_rings.go

@@ -1,4 +1,4 @@
-package zones
+package cluster
 
 import (
 	"bytes"
@@ -122,17 +122,15 @@ func (m *Machine) applyWireguardConfig(ring int, wg *wireguard.Config) error {
 	addr := wg.GetAddress()
 	zoneID, nodeID, ok := Rings[ring].Decode(addr)
 	if !ok {
-		return fmt.Errorf("%s: invalid wg%v address: %s", m.Name, ring, addr)
+		return fmt.Errorf("%s: invalid address", addr)
 	}
 
 	if err := m.applyZoneNodeID(zoneID, nodeID); err != nil {
-		err = core.Wrapf(err, "%s: wg%v:%s", m.Name, ring, addr)
-		return err
+		return core.Wrapf(err, "%s: invalid address", addr)
 	}
 
 	if err := m.applyWireguardInterfaceConfig(ring, wg.Interface); err != nil {
-		err = core.Wrapf(err, "%s: wg%v:%s", m.Name, ring, addr)
-		return err
+		return core.Wrap(err, "interface")
 	}
 
 	for _, peer := range wg.Peer {
@@ -140,9 +138,14 @@ func (m *Machine) applyWireguardConfig(ring int, wg *wireguard.Config) error {
 		switch {
 		case errors.Is(err, ErrUnknownNode):
 			// ignore unknown peers
+			m.warn(nil).
+				WithField("subsystem", "wireguard").
+				WithField("node", m.Name).
+				WithField("peer", peer.Endpoint.Host).
+				WithField("ring", ring).
+				Print("ignoring unknown endpoint")
 		case err != nil:
-			err = core.Wrapf(err, "%s: wg%v:%s", m.Name, ring, addr)
-			return err
+			return core.Wrap(err, "peer")
 		}
 	}
 
@@ -163,6 +166,10 @@ func (m *Machine) applyRingInfo(ring int, new *RingInfo) error {
 	cur, _ := m.getRingInfo(ring)
 	if cur == nil {
 		// first, append
+		m.debug().
+			WithField("node", m.Name).
+			WithField("ring", ring).
+			Print("found")
 		m.Rings = append(m.Rings, new)
 		return nil
 	}

pkg/cluster/machine_scan.go

@@ -1,4 +1,4 @@
-package zones
+package cluster
 
 import (
 	"context"
@@ -71,6 +71,11 @@ func (m *Machine) setID() error {
 func (m *Machine) scan(opts *ScanOptions) error {
 	for i := 0; i < RingsCount; i++ {
 		if err := m.tryApplyWireguardConfig(i); err != nil {
+			m.error(err).
+				WithField("subsystem", "wireguard").
+				WithField("node", m.Name).
+				WithField("ring", i).
+				Print()
 			return err
 		}
 	}

pkg/cluster/machines.go

@@ -0,0 +1,69 @@
+package cluster
+
+import "sort"
+
+var (
+	_ MachineIterator = Machines(nil)
+	_ sort.Interface  = Machines(nil)
+)
+
+// A MachineIterator is a set of Machines we can iterate on
+type MachineIterator interface {
+	ForEachMachine(func(*Machine) bool)
+}
+
+// Machines is a list of Machine objects
+type Machines []*Machine
+
+// ForEachMachine calls a function for each Machine in the list
+// until instructed to terminate the loop
+func (m Machines) ForEachMachine(fn func(*Machine) bool) {
+	for _, p := range m {
+		if fn(p) {
+			return
+		}
+	}
+}
+
+// Len returns the number of machines in the list
+func (m Machines) Len() int {
+	return len(m)
+}
+
+// Less implements sort.Interface to sort the list
+func (m Machines) Less(i, j int) bool {
+	a, b := m[i], m[j]
+	za, zb := a.Zone(), b.Zone()
+
+	switch {
+	case za == zb:
+		return a.ID < b.ID
+	default:
+		return za < zb
+	}
+}
+
+// Swap implements sort.Interface to sort the list
+func (m Machines) Swap(i, j int) {
+	m[i], m[j] = m[j], m[i]
+}
+
+// FilterMachines produces a subset of the machines offered by the given
+// iterator fulfilling a condition
+func FilterMachines(m MachineIterator, cond func(*Machine) bool) (Machines, int) {
+	var out []*Machine
+
+	if cond == nil {
+		// unconditional
+		cond = func(*Machine) bool { return true }
+	}
+
+	m.ForEachMachine(func(p *Machine) bool {
+		if cond(p) {
+			out = append(out, p)
+		}
+		return false
+	})
+
+	return out, len(out)
+}

pkg/cluster/regions.go

@@ -0,0 +1,130 @@
+package cluster
+
+var (
+	_ MachineIterator = (*Region)(nil)
+	_ ZoneIterator    = (*Region)(nil)
+)
+
+// Region represents a group of zones geographically related
+type Region struct {
+	m     *Cluster
+	zones []*Zone
+
+	Name    string
+	Regions []string `json:",omitempty" yaml:",omitempty"`
+}
+
+// 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
+		}
+	}
+}
+
+func (m *Cluster) initRegions(_ *ScanOptions) error {
+	regions := make(map[string][]*Zone)
+
+	// first regions defined by zones
+	m.ForEachZone(func(z *Zone) bool {
+		for _, region := range z.Regions {
+			regions[region] = append(regions[region], z)
+		}
+
+		return false
+	})
+
+	// bind first level regions and their zones
+	for name, zones := range regions {
+		m.syncRegions(name, zones...)
+	}
+
+	// and combine zones to produce larger regions
+	for i := range m.Regions {
+		r := &m.Regions[i]
+		m.finishRegion(r)
+	}
+
+	return nil
+}
+
+func (m *Cluster) syncRegions(name string, zones ...*Zone) {
+	for _, r := range m.Regions {
+		if r.Name == name {
+			// found
+			r.m = m
+			r.zones = zones
+			return
+		}
+	}
+
+	// new
+	m.Regions = append(m.Regions, Region{
+		m:     m,
+		zones: zones,
+		Name:  name,
+	})
+}
+
+func (m *Cluster) finishRegion(r *Region) {
+	if r.m != nil {
+		// ready
+		return
+	}
+
+	r.m = m
+	sub := []string{}
+	for _, name := range r.Regions {
+		r2, ok := m.getRegion(name)
+		if !ok {
+			m.warn(nil).WithField("region", name).Print("unknown region")
+			continue
+		}
+
+		sub = append(sub, r2.Name)
+		r.zones = append(r.zones, r2.zones...)
+	}
+	r.Regions = sub
+}
+
+func (m *Cluster) getRegion(name string) (*Region, bool) {
+	for i := range m.Regions {
+		r := &m.Regions[i]
+
+		if name == r.Name {
+			m.finishRegion(r)
+			return r, true
+		}
+	}
+
+	return nil, false
+}

pkg/cluster/rings.go

@@ -1,4 +1,4 @@
-package zones
+package cluster
 
 import (
 	"fmt"
@@ -24,9 +24,9 @@ const (
 // RingInfo contains represents the Wireguard endpoint details
 // for a Machine on a particular ring
 type RingInfo struct {
-	Ring    int               `toml:"ring"`
-	Enabled bool              `toml:"enabled,omitempty"`
-	Keys    wireguard.KeyPair `toml:"keys,omitempty"`
+	Ring    int
+	Enabled bool
+	Keys    wireguard.KeyPair
 }
 
 // Merge attempts to combine two RingInfo structs

pkg/cluster/sync.go

@@ -1,10 +1,11 @@
-package zones
+package cluster
 
 // SyncAll updates all config files
-func (m *Zones) SyncAll() error {
+func (m *Cluster) SyncAll() error {
 	for _, fn := range []func() error{
 		m.SyncAllWireguard,
 		m.SyncAllCeph,
+		m.WriteHosts,
 	} {
 		if err := fn(); err != nil {
 			return err
@@ -15,7 +16,7 @@ func (m *Zones) SyncAll() error {
 }
 
 // SyncAllWireguard updates all wireguard config files
-func (m *Zones) SyncAllWireguard() error {
+func (m *Cluster) SyncAllWireguard() error {
 	var err error
 
 	for ring := 0; ring < RingsCount; ring++ {
@@ -34,7 +35,7 @@ func (m *Zones) SyncAllWireguard() error {
 }
 
 // SyncAllCeph updates the ceph.conf file
-func (m *Zones) SyncAllCeph() error {
+func (m *Cluster) SyncAllCeph() error {
 	cfg, err := m.GenCephConfig()
 	if err != nil {
 		return err

pkg/cluster/wireguard.go

@@ -1,4 +1,4 @@
-package zones
+package cluster
 
 import (
 	"io/fs"
@@ -6,19 +6,19 @@ import (
 )
 
 var (
-	_ WireguardConfigPruner = (*Zones)(nil)
+	_ WireguardConfigPruner = (*Cluster)(nil)
 	_ WireguardConfigPruner = (*Zone)(nil)
 	_ WireguardConfigPruner = (*Machine)(nil)
 
-	_ WireguardConfigWriter = (*Zones)(nil)
+	_ WireguardConfigWriter = (*Cluster)(nil)
 	_ WireguardConfigWriter = (*Zone)(nil)
 	_ WireguardConfigWriter = (*Machine)(nil)
 
-	_ WireguardConfigSyncer = (*Zones)(nil)
+	_ WireguardConfigSyncer = (*Cluster)(nil)
 	_ WireguardConfigSyncer = (*Zone)(nil)
 	_ WireguardConfigSyncer = (*Machine)(nil)
 
-	_ WireguardKeysWriter = (*Zones)(nil)
+	_ WireguardKeysWriter = (*Cluster)(nil)
 	_ WireguardKeysWriter = (*Zone)(nil)
 	_ WireguardKeysWriter = (*Machine)(nil)
 )
@@ -31,7 +31,7 @@ type WireguardConfigPruner interface {
 
 // PruneWireguardConfig removes wgN.conf files of machines with
 // the corresponding ring disabled on all zones
-func (m *Zones) PruneWireguardConfig(ring int) error {
+func (m *Cluster) PruneWireguardConfig(ring int) error {
 	return pruneWireguardConfig(m, ring)
 }
 
@@ -76,7 +76,7 @@ type WireguardConfigWriter interface {
 
 // WriteWireguardConfig rewrites all wgN.conf on all machines
 // attached to that ring
-func (m *Zones) WriteWireguardConfig(ring int) error {
+func (m *Cluster) WriteWireguardConfig(ring int) error {
 	switch ring {
 	case 0:
 		return writeWireguardConfig(m, m, ring)
@@ -154,7 +154,7 @@ type WireguardConfigSyncer interface {
 
 // SyncWireguardConfig updates all wgN.conf files for the specified
 // ring
-func (m *Zones) SyncWireguardConfig(ring int) error {
+func (m *Cluster) SyncWireguardConfig(ring int) error {
 	switch ring {
 	case 0:
 		return syncWireguardConfig(m, m, ring)
@@ -214,7 +214,7 @@ type WireguardKeysWriter interface {
 }
 
 // WriteWireguardKeys rewrites all wgN.{key,pub} files
-func (m *Zones) WriteWireguardKeys(ring int) error {
+func (m *Cluster) WriteWireguardKeys(ring int) error {
 	return writeWireguardKeys(m, ring)
 }
 

pkg/cluster/zones.go

@@ -0,0 +1,69 @@
+package cluster
+
+import (
+	"io/fs"
+)
+
+var (
+	_ MachineIterator = (*Zone)(nil)
+)
+
+// A ZoneIterator is a set of Zones we can iterate on
+type ZoneIterator interface {
+	ForEachZone(func(*Zone) bool)
+}
+
+// A Zone is a set of machines in close proximity and strong
+// affinity.
+type Zone struct {
+	zones  *Cluster
+	logger `json:"-" yaml:"-"`
+
+	ID      int
+	Name    string
+	Regions []string `json:",omitempty" yaml:",omitempty"`
+
+	Machines
+}
+
+func (z *Zone) String() string {
+	return z.Name
+}
+
+// SetGateway configures a machine to be the zone's ring0 gateway
+func (z *Zone) SetGateway(gatewayID int, enabled bool) error {
+	var err error
+	var found bool
+
+	z.ForEachMachine(func(p *Machine) bool {
+		if p.ID == gatewayID {
+			found = true
+			err = p.SetGateway(enabled)
+
+			return true
+		}
+		return false
+	})
+
+	switch {
+	case err != nil:
+		return err
+	case !found:
+		return fs.ErrNotExist
+	default:
+		return nil
+	}
+}
+
+// GatewayIDs returns the list of IDs of machines that act as ring0 gateways
+func (z *Zone) GatewayIDs() ([]int, int) {
+	var out []int
+	z.ForEachMachine(func(p *Machine) bool {
+		if p.IsGateway() {
+			out = append(out, p.ID)
+		}
+		return false
+	})
+
+	return out, len(out)
+}

pkg/dns/dns.go

@@ -0,0 +1,38 @@
+// Package dns manages DNS entries for the cluster
+package dns
+
+import (
+	"fmt"
+	"net/netip"
+)
+
+// Zone represents a set of hosts with high affinity
+type Zone struct {
+	Name string
+
+	Hosts map[int]*Host
+}
+
+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/manager.go

@@ -0,0 +1,173 @@
+package dns
+
+import (
+	"context"
+	"errors"
+	"io/fs"
+	"net/netip"
+	"strings"
+
+	"darvaza.org/core"
+	"darvaza.org/slog"
+	"git.jpi.io/amery/jpictl/pkg/cluster"
+	"golang.org/x/net/publicsuffix"
+)
+
+// Manager is a DNS Manager instance
+type Manager struct {
+	domain  string
+	suffix  string
+	zones   map[string]*Zone
+	regions map[string][]string
+
+	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 {
+		return core.Wrap(err, hint)
+	}
+}
+
+// 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.l == nil {
+		opts = append(opts, WithLogger(nil))
+	}
+
+	if mgr.domain == "" || mgr.suffix == "" {
+		return errors.New("domain not specified")
+	}
+
+	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 := &Manager{
+		zones:   make(map[string]*Zone),
+		regions: make(map[string][]string),
+	}
+
+	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
+}
+
+// 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

@@ -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/record.go

@@ -0,0 +1,212 @@
+package dns
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"net/netip"
+	"sort"
+	"time"
+
+	"darvaza.org/core"
+	"github.com/libdns/libdns"
+)
+
+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])
+	})
+	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
+	Addr []netip.Addr
+}
+
+// Sort sorts the addresses of the record
+func (rr *AddrRecord) Sort() {
+	SortAddrSlice(rr.Addr)
+}
+
+// Export converts the record into libdns.Record
+func (rr *AddrRecord) Export() []libdns.Record {
+	out := make([]libdns.Record, len(rr.Addr))
+	for i, addr := range rr.Addr {
+		out[i] = libdns.Record{
+			Name:  rr.Name,
+			TTL:   time.Second * 1,
+			Type:  core.IIf(addr.Is6(), "AAAA", "A"),
+			Value: addr.String(),
+		}
+	}
+
+	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
+
+	cache := make(map[string][]netip.Addr)
+
+	// zones
+	for _, z := range mgr.zones {
+		// hosts
+		s := mgr.genZoneHostRecords(z)
+		out = append(out, s...)
+
+		// zone alias
+		addrs := mgr.genZoneAddresses(z)
+		name := z.Name
+
+		out = append(out, AddrRecord{
+			Name: name + mgr.suffix,
+			Addr: addrs,
+		})
+
+		// and cache for regions
+		cache[name] = addrs
+	}
+
+	for _, name := range mgr.genRegionsSorted() {
+		var addrs []netip.Addr
+
+		for _, z := range mgr.regions[name] {
+			addrs = append(addrs, cache[z]...)
+		}
+
+		rec := AddrRecord{
+			Name: name + mgr.suffix,
+			Addr: addrs,
+		}
+		rec.Sort()
+
+		out = append(out, rec)
+	}
+
+	return out
+}
+
+func (*Manager) genZoneAddresses(z *Zone) []netip.Addr {
+	var out []netip.Addr
+
+	for _, p := range z.Hosts {
+		if p.Active {
+			out = append(out, p.Addrs...)
+		}
+	}
+
+	SortAddrSlice(out)
+	return out
+}
+
+func (mgr *Manager) genZoneHostRecords(z *Zone) []AddrRecord {
+	out := make([]AddrRecord, 0, len(z.Hosts))
+
+	for _, p := range z.Hosts {
+		rec := AddrRecord{
+			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/write.go

@@ -0,0 +1,62 @@
+package dns
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"net/netip"
+)
+
+// WriteTo writes the DNS data for the cluster
+func (mgr *Manager) WriteTo(w io.Writer) (int64, error) {
+	var buf bytes.Buffer
+
+	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
+	}
+
+	// regions, sorted
+	for _, name := range mgr.genRegionsSorted() {
+		addrs := mgr.genRegionAddressesCached(name, cache)
+
+		mgr.writeRegionAddresses(&buf, name, addrs)
+	}
+
+	return buf.WriteTo(w)
+}
+
+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/zones/ceph_scan.go

@@ -1,183 +0,0 @@
-package zones
-
-import (
-	"net/netip"
-	"os"
-	"strings"
-
-	"darvaza.org/core"
-	"git.jpi.io/amery/jpictl/pkg/ceph"
-)
-
-// CephMissingMonitorError is an error that contains ceph
-// monitors present in ceph.conf but not found on the cluster
-type CephMissingMonitorError struct {
-	Names []string
-	Addrs []netip.Addr
-}
-
-func (err *CephMissingMonitorError) appendName(name string) {
-	err.Names = append(err.Names, name)
-}
-
-func (err *CephMissingMonitorError) appendAddr(addr netip.Addr) {
-	err.Addrs = append(err.Addrs, addr)
-}
-
-// OK tells if this instance actual shouldn't be treated as an error
-func (err CephMissingMonitorError) OK() bool {
-	switch {
-	case len(err.Names) > 0:
-		return false
-	case len(err.Addrs) > 0:
-		return false
-	default:
-		return true
-	}
-}
-
-func (err CephMissingMonitorError) Error() string {
-	if !err.OK() {
-		var buf strings.Builder
-
-		_, _ = buf.WriteString("missing:")
-		err.writeNames(&buf)
-		err.writeAddrs(&buf)
-
-		return buf.String()
-	}
-
-	// no error
-	return ""
-}
-
-func (err *CephMissingMonitorError) writeNames(w *strings.Builder) {
-	if len(err.Names) > 0 {
-		_, _ = w.WriteString(" mon_initial_members:")
-		for i, name := range err.Names {
-			if i != 0 {
-				_, _ = w.WriteRune(',')
-			}
-			_, _ = w.WriteString(name)
-		}
-	}
-}
-
-func (err *CephMissingMonitorError) writeAddrs(w *strings.Builder) {
-	if len(err.Addrs) > 0 {
-		_, _ = w.WriteString(" mon_host:")
-		for i, addr := range err.Addrs {
-			if i != 0 {
-				_, _ = w.WriteRune(',')
-			}
-			_, _ = w.WriteString(addr.String())
-		}
-	}
-}
-
-// AsError returns nil if the instance is actually OK
-func (err *CephMissingMonitorError) AsError() error {
-	if err == nil || err.OK() {
-		return nil
-	}
-
-	return err
-}
-
-type cephScanTODO struct {
-	names map[string]bool
-	addrs map[string]bool
-}
-
-func (todo *cephScanTODO) checkMachine(p *Machine) bool {
-	// on ceph all addresses are ring1
-	ring1, _ := RingOneAddress(p.Zone(), p.ID)
-	addr := ring1.String()
-
-	if _, found := todo.names[p.Name]; found {
-		// found on the TODO by name
-		todo.names[p.Name] = true
-		todo.addrs[addr] = true
-		return true
-	}
-
-	if _, found := todo.addrs[addr]; found {
-		// found on the TODO by address
-		todo.names[p.Name] = true
-		todo.addrs[addr] = true
-		return true
-	}
-
-	return false
-}
-
-func (todo *cephScanTODO) Missing() error {
-	var check CephMissingMonitorError
-
-	for name, found := range todo.names {
-		if !found {
-			check.appendName(name)
-		}
-	}
-
-	for addr, found := range todo.addrs {
-		if !found {
-			var a netip.Addr
-			// it wouldn't be on the map if it wasn't valid
-			_ = a.UnmarshalText([]byte(addr))
-
-			check.appendAddr(a)
-		}
-	}
-
-	return check.AsError()
-}
-
-func newCephScanTODO(cfg *ceph.Config) *cephScanTODO {
-	todo := &cephScanTODO{
-		names: make(map[string]bool),
-		addrs: make(map[string]bool),
-	}
-
-	for _, name := range cfg.Global.Monitors {
-		todo.names[name] = false
-	}
-
-	for _, addr := range cfg.Global.MonitorsAddr {
-		todo.addrs[addr.String()] = false
-	}
-
-	return todo
-}
-
-func (m *Zones) scanCephMonitors(_ *ScanOptions) error {
-	cfg, err := m.GetCephConfig()
-	switch {
-	case os.IsNotExist(err):
-		err = nil
-	case err != nil:
-		return err
-	}
-
-	if cfg != nil {
-		// store FSID
-		m.CephFSID = cfg.Global.FSID
-
-		// flag monitors based on config
-		todo := newCephScanTODO(cfg)
-		m.ForEachMachine(func(p *Machine) bool {
-			p.CephMonitor = todo.checkMachine(p)
-			return false
-		})
-		if err := todo.Missing(); err != nil {
-			return core.Wrap(err, "ceph")
-		}
-	}
-
-	// make sure every zone has one
-	m.ForEachZone(func(z *Zone) bool {
-		_ = z.GetCephMonitors()
-		return false
-	})
-	return nil
-}

pkg/zones/zones.go

@@ -1,199 +0,0 @@
-// Package zones contains information about the cluster
-package zones
-
-import (
-	"io/fs"
-	"sort"
-
-	"darvaza.org/resolver"
-	"darvaza.org/slog"
-	"github.com/gofrs/uuid/v5"
-)
-
-var (
-	_ MachineIterator = Machines(nil)
-	_ sort.Interface  = Machines(nil)
-
-	_ MachineIterator = (*Zone)(nil)
-	_ MachineIterator = (*Zones)(nil)
-	_ ZoneIterator    = (*Zones)(nil)
-)
-
-// A MachineIterator is a set of Machines we can iterate on
-type MachineIterator interface {
-	ForEachMachine(func(*Machine) bool)
-}
-
-// A ZoneIterator is a set of Zones we can iterate on
-type ZoneIterator interface {
-	ForEachZone(func(*Zone) bool)
-}
-
-// Machines is a list of Machine objects
-type Machines []*Machine
-
-// ForEachMachine calls a function for each Machine in the list
-// until instructed to terminate the loop
-func (m Machines) ForEachMachine(fn func(*Machine) bool) {
-	for _, p := range m {
-		if fn(p) {
-			return
-		}
-	}
-}
-
-// Len returns the number of machines in the list
-func (m Machines) Len() int {
-	return len(m)
-}
-
-// Less implements sort.Interface to sort the list
-func (m Machines) Less(i, j int) bool {
-	a, b := m[i], m[j]
-	za, zb := a.Zone(), b.Zone()
-
-	switch {
-	case za == zb:
-		return a.ID < b.ID
-	default:
-		return za < zb
-	}
-}
-
-// Swap implements sort.Interface to sort the list
-func (m Machines) Swap(i, j int) {
-	m[i], m[j] = m[j], m[i]
-}
-
-// FilterMachines produces a subset of the machines offered by the given
-// iterator fulfilling a condition
-func FilterMachines(m MachineIterator, cond func(*Machine) bool) (Machines, int) {
-	var out []*Machine
-
-	if cond == nil {
-		// unconditional
-		cond = func(*Machine) bool { return true }
-	}
-
-	m.ForEachMachine(func(p *Machine) bool {
-		if cond(p) {
-			out = append(out, p)
-		}
-		return false
-	})
-
-	return out, len(out)
-}
-
-// Zone represents one zone in a cluster
-type Zone struct {
-	zones  *Zones
-	logger `toml:"-" json:"-" yaml:"-"`
-
-	ID   int    `toml:"id"`
-	Name string `toml:"name"`
-
-	Machines `toml:"machines"`
-}
-
-func (z *Zone) String() string {
-	return z.Name
-}
-
-// SetGateway configures a machine to be the zone's ring0 gateway
-func (z *Zone) SetGateway(gatewayID int, enabled bool) error {
-	var err error
-	var found bool
-
-	z.ForEachMachine(func(p *Machine) bool {
-		if p.ID == gatewayID {
-			found = true
-			err = p.SetGateway(enabled)
-
-			return true
-		}
-		return false
-	})
-
-	switch {
-	case err != nil:
-		return err
-	case !found:
-		return fs.ErrNotExist
-	default:
-		return nil
-	}
-}
-
-// GatewayIDs returns the list of IDs of machines that act as ring0 gateways
-func (z *Zone) GatewayIDs() ([]int, int) {
-	var out []int
-	z.ForEachMachine(func(p *Machine) bool {
-		if p.IsGateway() {
-			out = append(out, p.ID)
-		}
-		return false
-	})
-
-	return out, len(out)
-}
-
-// revive:disable:line-length-limit
-
-// Zones represents all zones in a cluster
-type Zones struct {
-	dir      fs.FS
-	log      slog.Logger
-	resolver resolver.Resolver
-	domain   string
-
-	CephFSID uuid.UUID `toml:"ceph_fsid,omitempty" json:"ceph_fsid,omitempty" yaml:"ceph_fsid,omitempty"`
-
-	Zones []*Zone `toml:"zones"`
-}
-
-// revive:enable:line-length-limit
-
-// ForEachMachine calls a function for each Machine in the cluster
-// until instructed to terminate the loop
-func (m *Zones) ForEachMachine(fn func(*Machine) bool) {
-	m.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 cluster
-// until instructed to terminate the loop
-func (m *Zones) ForEachZone(fn func(*Zone) bool) {
-	for _, p := range m.Zones {
-		if fn(p) {
-			// terminate
-			return
-		}
-	}
-}
-
-// GetMachineByName looks for a machine with the specified
-// name on any zone
-func (m *Zones) GetMachineByName(name string) (*Machine, bool) {
-	var out *Machine
-
-	if name != "" {
-		m.ForEachMachine(func(p *Machine) bool {
-			if p.Name == name {
-				out = p
-			}
-
-			return out != nil
-		})
-	}
-
-	return out, out != nil
-}