"discovery: mDNS/DNS-SD peer discovery; dynamic upstream management"
Allows ncro instances to discover each other dynamically without static configuration and enables a peer-to-peer style (hello funny cube) mesh where nodes share cached builds locally instead of all hitting upstream caches. Signed-off-by: NotAShelf <raf@notashelf.dev> Change-Id: I7d723876c6816cb6aaaf3fe14cb24a426a6a6964
This commit is contained in:
parent
7aee098f1c
commit
5fc3b2883b
GPG key ID:
29D95B64378DB4BF
6 changed files with 336 additions and 3 deletions
|
|
@ -18,6 +18,7 @@ import (
|
|||
"github.com/spf13/viper"
|
||||
"notashelf.dev/ncro/internal/cache"
|
||||
"notashelf.dev/ncro/internal/config"
|
||||
"notashelf.dev/ncro/internal/discovery"
|
||||
"notashelf.dev/ncro/internal/mesh"
|
||||
"notashelf.dev/ncro/internal/metrics"
|
||||
"notashelf.dev/ncro/internal/prober"
|
||||
|
|
@ -132,6 +133,26 @@ func runServer(_ *cobra.Command, _ []string) error {
|
|||
probeDone := make(chan struct{})
|
||||
go p.RunProbeLoop(30*time.Second, probeDone)
|
||||
|
||||
// Setup mDNS discovery if enabled
|
||||
var discoveryMgr *discovery.Discovery
|
||||
if cfg.Discovery.Enabled {
|
||||
discoveryMgr, err = discovery.New(cfg.Discovery, p)
|
||||
if err != nil {
|
||||
return fmt.Errorf("create discovery manager: %w", err)
|
||||
}
|
||||
discoveryMgr.SetCallbacks(
|
||||
func(url string, priority int) {
|
||||
slog.Info("adding discovered upstream", "url", url)
|
||||
p.AddUpstream(url, priority)
|
||||
},
|
||||
func(url string) {
|
||||
slog.Info("removing discovered upstream", "url", url)
|
||||
p.RemoveUpstream(url)
|
||||
},
|
||||
)
|
||||
slog.Info("mDNS discovery enabled", "service", cfg.Discovery.ServiceName)
|
||||
}
|
||||
|
||||
r := router.New(db, p, cfg.Cache.TTL.Duration, 5*time.Second, cfg.Cache.NegativeTTL.Duration)
|
||||
for _, u := range cfg.Upstreams {
|
||||
if u.PublicKey != "" {
|
||||
|
|
@ -174,6 +195,22 @@ func runServer(_ *cobra.Command, _ []string) error {
|
|||
slog.Info("mesh enabled", "addr", cfg.Mesh.BindAddr, "peers", len(cfg.Mesh.Peers))
|
||||
}
|
||||
|
||||
// Start mDNS discovery in background
|
||||
discoveryDone := make(chan struct{})
|
||||
if discoveryMgr != nil {
|
||||
go func() {
|
||||
ctx, cancel := context.WithCancel(context.Background())
|
||||
defer cancel()
|
||||
if err := discoveryMgr.Start(ctx); err != nil {
|
||||
slog.Error("discovery error", "error", err)
|
||||
}
|
||||
}()
|
||||
go func() {
|
||||
<-discoveryDone
|
||||
discoveryMgr.Stop()
|
||||
}()
|
||||
}
|
||||
|
||||
srv := &http.Server{
|
||||
Addr: cfg.Server.Listen,
|
||||
Handler: server.New(r, p, db, cfg.Upstreams, cfg.Server.CachePriority),
|
||||
|
|
@ -206,6 +243,7 @@ func runServer(_ *cobra.Command, _ []string) error {
|
|||
if gossipDone != nil {
|
||||
close(gossipDone)
|
||||
}
|
||||
close(discoveryDone)
|
||||
|
||||
ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
|
||||
defer cancel()
|
||||
|
|
|
|||
7
go.mod
7
go.mod
|
|
@ -3,6 +3,7 @@ module notashelf.dev/ncro
|
|||
go 1.25.7
|
||||
|
||||
require (
|
||||
github.com/grandcat/zeroconf v1.0.0
|
||||
github.com/prometheus/client_golang v1.23.2
|
||||
github.com/spf13/cobra v1.10.2
|
||||
github.com/spf13/viper v1.21.0
|
||||
|
|
@ -14,6 +15,7 @@ require (
|
|||
|
||||
require (
|
||||
github.com/beorn7/perks v1.0.1 // indirect
|
||||
github.com/cenkalti/backoff v2.2.1+incompatible // indirect
|
||||
github.com/cespare/xxhash/v2 v2.3.0 // indirect
|
||||
github.com/dustin/go-humanize v1.0.1 // indirect
|
||||
github.com/fsnotify/fsnotify v1.9.0 // indirect
|
||||
|
|
@ -21,6 +23,7 @@ require (
|
|||
github.com/google/uuid v1.6.0 // indirect
|
||||
github.com/inconshreveable/mousetrap v1.1.0 // indirect
|
||||
github.com/mattn/go-isatty v0.0.20 // indirect
|
||||
github.com/miekg/dns v1.1.27 // indirect
|
||||
github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 // indirect
|
||||
github.com/ncruces/go-strftime v1.0.0 // indirect
|
||||
github.com/pelletier/go-toml/v2 v2.2.4 // indirect
|
||||
|
|
@ -37,8 +40,10 @@ require (
|
|||
github.com/vmihailenco/tagparser/v2 v2.0.0 // indirect
|
||||
go.yaml.in/yaml/v2 v2.4.3 // indirect
|
||||
go.yaml.in/yaml/v3 v3.0.4 // indirect
|
||||
golang.org/x/crypto v0.48.0 // indirect
|
||||
golang.org/x/net v0.50.0 // indirect
|
||||
golang.org/x/sys v0.41.0 // indirect
|
||||
golang.org/x/text v0.32.0 // indirect
|
||||
golang.org/x/text v0.34.0 // indirect
|
||||
golang.org/x/tools v0.42.0 // indirect
|
||||
google.golang.org/protobuf v1.36.11 // indirect
|
||||
modernc.org/libc v1.69.0 // indirect
|
||||
|
|
|
|||
30
go.sum
30
go.sum
|
|
@ -1,5 +1,7 @@
|
|||
github.com/beorn7/perks v1.0.1 h1:VlbKKnNfV8bJzeqoa4cOKqO6bYr3WgKZxO8Z16+hsOM=
|
||||
github.com/beorn7/perks v1.0.1/go.mod h1:G2ZrVWU2WbWT9wwq4/hrbKbnv/1ERSJQ0ibhJ6rlkpw=
|
||||
github.com/cenkalti/backoff v2.2.1+incompatible h1:tNowT99t7UNflLxfYYSlKYsBpXdEet03Pg2g16Swow4=
|
||||
github.com/cenkalti/backoff v2.2.1+incompatible/go.mod h1:90ReRw6GdpyfrHakVjL/QHaoyV4aDUVVkXQJJJ3NXXM=
|
||||
github.com/cespare/xxhash/v2 v2.3.0 h1:UL815xU9SqsFlibzuggzjXhog7bL6oX9BbNZnL2UFvs=
|
||||
github.com/cespare/xxhash/v2 v2.3.0/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
|
||||
github.com/cpuguy83/go-md2man/v2 v2.0.6/go.mod h1:oOW0eioCTA6cOiMLiUPZOpcVxMig6NIQQ7OS05n1F4g=
|
||||
|
|
@ -19,6 +21,8 @@ github.com/google/pprof v0.0.0-20250317173921-a4b03ec1a45e h1:ijClszYn+mADRFY17k
|
|||
github.com/google/pprof v0.0.0-20250317173921-a4b03ec1a45e/go.mod h1:boTsfXsheKC2y+lKOCMpSfarhxDeIzfZG1jqGcPl3cA=
|
||||
github.com/google/uuid v1.6.0 h1:NIvaJDMOsjHA8n1jAhLSgzrAzy1Hgr+hNrb57e+94F0=
|
||||
github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
|
||||
github.com/grandcat/zeroconf v1.0.0 h1:uHhahLBKqwWBV6WZUDAT71044vwOTL+McW0mBJvo6kE=
|
||||
github.com/grandcat/zeroconf v1.0.0/go.mod h1:lTKmG1zh86XyCoUeIHSA4FJMBwCJiQmGfcP2PdzytEs=
|
||||
github.com/hashicorp/golang-lru/v2 v2.0.7 h1:a+bsQ5rvGLjzHuww6tVxozPZFVghXaHOwFs4luLUK2k=
|
||||
github.com/hashicorp/golang-lru/v2 v2.0.7/go.mod h1:QeFd9opnmA6QUJc5vARoKUSoFhyfM2/ZepoAG6RGpeM=
|
||||
github.com/inconshreveable/mousetrap v1.1.0 h1:wN+x4NVGpMsO7ErUn/mUI3vEoE6Jt13X2s0bqwp9tc8=
|
||||
|
|
@ -33,12 +37,16 @@ github.com/kylelemons/godebug v1.1.0 h1:RPNrshWIDI6G2gRW9EHilWtl7Z6Sb1BR0xunSBf0
|
|||
github.com/kylelemons/godebug v1.1.0/go.mod h1:9/0rRGxNHcop5bhtWyNeEfOS8JIWk580+fNqagV/RAw=
|
||||
github.com/mattn/go-isatty v0.0.20 h1:xfD0iDuEKnDkl03q4limB+vH+GxLEtL/jb4xVJSWWEY=
|
||||
github.com/mattn/go-isatty v0.0.20/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D7dTCTo3Y=
|
||||
github.com/miekg/dns v1.1.27 h1:aEH/kqUzUxGJ/UHcEKdJY+ugH6WEzsEBBSPa8zuy1aM=
|
||||
github.com/miekg/dns v1.1.27/go.mod h1:KNUDUusw/aVsxyTYZM1oqvCicbwhgbNgztCETuNZ7xM=
|
||||
github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 h1:C3w9PqII01/Oq1c1nUAm88MOHcQC9l5mIlSMApZMrHA=
|
||||
github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822/go.mod h1:+n7T8mK8HuQTcFwEeznm/DIxMOiR9yIdICNftLE1DvQ=
|
||||
github.com/ncruces/go-strftime v1.0.0 h1:HMFp8mLCTPp341M/ZnA4qaf7ZlsbTc+miZjCLOFAw7w=
|
||||
github.com/ncruces/go-strftime v1.0.0/go.mod h1:Fwc5htZGVVkseilnfgOVb9mKy6w1naJmn9CehxcKcls=
|
||||
github.com/pelletier/go-toml/v2 v2.2.4 h1:mye9XuhQ6gvn5h28+VilKrrPoQVanw5PMw/TB0t5Ec4=
|
||||
github.com/pelletier/go-toml/v2 v2.2.4/go.mod h1:2gIqNv+qfxSVS7cM2xJQKtLSTLUE9V8t9Stt+h56mCY=
|
||||
github.com/pkg/errors v0.9.1 h1:FEBLx1zS214owpjy7qsBeixbURkuhQAwrK5UwLGTwt4=
|
||||
github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
|
||||
github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
|
||||
github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
|
||||
github.com/prometheus/client_golang v1.23.2 h1:Je96obch5RDVy3FDMndoUsjAhG5Edi49h0RJWRi/o0o=
|
||||
|
|
@ -83,17 +91,35 @@ go.yaml.in/yaml/v2 v2.4.3 h1:6gvOSjQoTB3vt1l+CU+tSyi/HOjfOjRLJ4YwYZGwRO0=
|
|||
go.yaml.in/yaml/v2 v2.4.3/go.mod h1:zSxWcmIDjOzPXpjlTTbAsKokqkDNAVtZO0WOMiT90s8=
|
||||
go.yaml.in/yaml/v3 v3.0.4 h1:tfq32ie2Jv2UxXFdLJdh3jXuOzWiL1fo0bu/FbuKpbc=
|
||||
go.yaml.in/yaml/v3 v3.0.4/go.mod h1:DhzuOOF2ATzADvBadXxruRBLzYTpT36CKvDb3+aBEFg=
|
||||
golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
|
||||
golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
|
||||
golang.org/x/crypto v0.48.0 h1:/VRzVqiRSggnhY7gNRxPauEQ5Drw9haKdM0jqfcCFts=
|
||||
golang.org/x/crypto v0.48.0/go.mod h1:r0kV5h3qnFPlQnBSrULhlsRfryS2pmewsg+XfMgkVos=
|
||||
golang.org/x/mod v0.1.1-0.20191105210325-c90efee705ee/go.mod h1:QqPTAvyqsEbceGzBzNggFXnrqF1CaUcvgkdR5Ot7KZg=
|
||||
golang.org/x/mod v0.33.0 h1:tHFzIWbBifEmbwtGz65eaWyGiGZatSrT9prnU8DbVL8=
|
||||
golang.org/x/mod v0.33.0/go.mod h1:swjeQEj+6r7fODbD2cqrnje9PnziFuw4bmLbBZFrQ5w=
|
||||
golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
|
||||
golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
|
||||
golang.org/x/net v0.0.0-20190923162816-aa69164e4478/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
|
||||
golang.org/x/net v0.0.0-20200114155413-6afb5195e5aa/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
|
||||
golang.org/x/net v0.50.0 h1:ucWh9eiCGyDR3vtzso0WMQinm2Dnt8cFMuQa9K33J60=
|
||||
golang.org/x/net v0.50.0/go.mod h1:UgoSli3F/pBgdJBHCTc+tp3gmrU4XswgGRgtnwWTfyM=
|
||||
golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
|
||||
golang.org/x/sync v0.19.0 h1:vV+1eWNmZ5geRlYjzm2adRgW2/mcpevXNg50YZtPCE4=
|
||||
golang.org/x/sync v0.19.0/go.mod h1:9KTHXmSnoGruLpwFjVSX0lNNA75CykiMECbovNTZqGI=
|
||||
golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
|
||||
golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
|
||||
golang.org/x/sys v0.0.0-20190924154521-2837fb4f24fe/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
|
||||
golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
|
||||
golang.org/x/sys v0.41.0 h1:Ivj+2Cp/ylzLiEU89QhWblYnOE9zerudt9Ftecq2C6k=
|
||||
golang.org/x/sys v0.41.0/go.mod h1:OgkHotnGiDImocRcuBABYBEXf8A9a87e/uXjp9XT3ks=
|
||||
golang.org/x/text v0.32.0 h1:ZD01bjUt1FQ9WJ0ClOL5vxgxOI/sVCNgX1YtKwcY0mU=
|
||||
golang.org/x/text v0.32.0/go.mod h1:o/rUWzghvpD5TXrTIBuJU77MTaN0ljMWE47kxGJQ7jY=
|
||||
golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
|
||||
golang.org/x/text v0.34.0 h1:oL/Qq0Kdaqxa1KbNeMKwQq0reLCCaFtqu2eNuSeNHbk=
|
||||
golang.org/x/text v0.34.0/go.mod h1:homfLqTYRFyVYemLBFl5GgL/DWEiH5wcsQ5gSh1yziA=
|
||||
golang.org/x/tools v0.0.0-20191216052735-49a3e744a425/go.mod h1:TB2adYChydJhpapKDTa4BR/hXlZSLoq2Wpct/0txZ28=
|
||||
golang.org/x/tools v0.42.0 h1:uNgphsn75Tdz5Ji2q36v/nsFSfR/9BRFvqhGBaJGd5k=
|
||||
golang.org/x/tools v0.42.0/go.mod h1:Ma6lCIwGZvHK6XtgbswSoWroEkhugApmsXyrUmBhfr0=
|
||||
golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
|
||||
google.golang.org/protobuf v1.36.11 h1:fV6ZwhNocDyBLK0dj+fg8ektcVegBBuEolpbTQyBNVE=
|
||||
google.golang.org/protobuf v1.36.11/go.mod h1:HTf+CrKn2C3g5S8VImy6tdcUvCska2kB7j23XfzDpco=
|
||||
gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
|
||||
|
|
|
|||
|
|
@ -71,6 +71,15 @@ type MeshConfig struct {
|
|||
GossipInterval Duration `yaml:"gossip_interval"`
|
||||
}
|
||||
|
||||
// Controls mDNS/DNS-SD based dynamic upstream discovery.
|
||||
type DiscoveryConfig struct {
|
||||
Enabled bool `yaml:"enabled"`
|
||||
ServiceName string `yaml:"service_name"`
|
||||
Domain string `yaml:"domain"`
|
||||
DiscoveryTime Duration `yaml:"discovery_time"`
|
||||
Priority int `yaml:"priority"`
|
||||
}
|
||||
|
||||
type LoggingConfig struct {
|
||||
Level string `yaml:"level"`
|
||||
Format string `yaml:"format"`
|
||||
|
|
@ -81,6 +90,7 @@ type Config struct {
|
|||
Upstreams []UpstreamConfig `yaml:"upstreams"`
|
||||
Cache CacheConfig `yaml:"cache"`
|
||||
Mesh MeshConfig `yaml:"mesh"`
|
||||
Discovery DiscoveryConfig `yaml:"discovery"`
|
||||
Logging LoggingConfig `yaml:"logging"`
|
||||
}
|
||||
|
||||
|
|
@ -106,6 +116,12 @@ func defaults() Config {
|
|||
BindAddr: "0.0.0.0:7946",
|
||||
GossipInterval: Duration{30 * time.Second},
|
||||
},
|
||||
Discovery: DiscoveryConfig{
|
||||
ServiceName: "_nix-serve._tcp",
|
||||
Domain: "local",
|
||||
DiscoveryTime: Duration{5 * time.Second},
|
||||
Priority: 20,
|
||||
},
|
||||
Logging: LoggingConfig{
|
||||
Level: "info",
|
||||
Format: "json",
|
||||
|
|
@ -161,6 +177,17 @@ func (c *Config) Validate() error {
|
|||
}
|
||||
}
|
||||
}
|
||||
if c.Discovery.Enabled {
|
||||
if c.Discovery.ServiceName == "" {
|
||||
return fmt.Errorf("discovery.service_name is required when discovery is enabled")
|
||||
}
|
||||
if c.Discovery.Domain == "" {
|
||||
return fmt.Errorf("discovery.domain is required when discovery is enabled")
|
||||
}
|
||||
if c.Discovery.DiscoveryTime.Duration <= 0 {
|
||||
return fmt.Errorf("discovery.discovery_time must be positive")
|
||||
}
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
|
|
|
|||
216
internal/discovery/discovery.go
Normal file
216
internal/discovery/discovery.go
Normal file
|
|
@ -0,0 +1,216 @@
|
|||
package discovery
|
||||
|
||||
import (
|
||||
"context"
|
||||
"fmt"
|
||||
"log/slog"
|
||||
"sync"
|
||||
"time"
|
||||
|
||||
"github.com/grandcat/zeroconf"
|
||||
"notashelf.dev/ncro/internal/config"
|
||||
"notashelf.dev/ncro/internal/prober"
|
||||
)
|
||||
|
||||
// Tracks discovered nix-serve instances and maintains the upstream list.
|
||||
type Discovery struct {
|
||||
cfg config.DiscoveryConfig
|
||||
prober *prober.Prober
|
||||
resolver *zeroconf.Resolver
|
||||
discovered map[string]*discoveredPeer
|
||||
mu sync.RWMutex
|
||||
stopCh chan struct{}
|
||||
waitGroup sync.WaitGroup
|
||||
onAddUpstream func(url string, priority int)
|
||||
onRemoveUpstream func(url string)
|
||||
}
|
||||
|
||||
type discoveredPeer struct {
|
||||
url string
|
||||
lastSeen time.Time
|
||||
}
|
||||
|
||||
// Creates a new Discovery manager.
|
||||
func New(cfg config.DiscoveryConfig, p *prober.Prober) (*Discovery, error) {
|
||||
resolver, err := zeroconf.NewResolver(nil)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("create zeroconf resolver: %w", err)
|
||||
}
|
||||
|
||||
return &Discovery{
|
||||
cfg: cfg,
|
||||
prober: p,
|
||||
resolver: resolver,
|
||||
discovered: make(map[string]*discoveredPeer),
|
||||
stopCh: make(chan struct{}),
|
||||
}, nil
|
||||
}
|
||||
|
||||
// Sets callbacks for upstream addition/removal. These are invoked when peers
|
||||
// are discovered or leave the network.
|
||||
func (d *Discovery) SetCallbacks(
|
||||
add func(url string, priority int),
|
||||
remove func(url string),
|
||||
) {
|
||||
d.mu.Lock()
|
||||
defer d.mu.Unlock()
|
||||
d.onAddUpstream = add
|
||||
d.onRemoveUpstream = remove
|
||||
}
|
||||
|
||||
// Starts browsing for services on the local network. Blocks until the context
|
||||
// is cancelled or Stop is called.
|
||||
func (d *Discovery) Start(ctx context.Context) error {
|
||||
entries := make(chan *zeroconf.ServiceEntry)
|
||||
|
||||
d.waitGroup.Add(1)
|
||||
go d.handleEntries(ctx, entries)
|
||||
|
||||
d.waitGroup.Add(1)
|
||||
go d.maintainPeers(ctx)
|
||||
|
||||
if err := d.resolver.Browse(ctx, d.cfg.ServiceName, d.cfg.Domain, entries); err != nil {
|
||||
close(entries)
|
||||
d.waitGroup.Wait()
|
||||
return fmt.Errorf("browse services: %w", err)
|
||||
}
|
||||
|
||||
select {
|
||||
case <-ctx.Done():
|
||||
return ctx.Err()
|
||||
case <-d.stopCh:
|
||||
return nil
|
||||
}
|
||||
}
|
||||
|
||||
// Stops the discovery process.
|
||||
func (d *Discovery) Stop() {
|
||||
close(d.stopCh)
|
||||
d.waitGroup.Wait()
|
||||
}
|
||||
|
||||
// Processes discovered service entries.
|
||||
func (d *Discovery) handleEntries(ctx context.Context, entries chan *zeroconf.ServiceEntry) {
|
||||
defer d.waitGroup.Done()
|
||||
|
||||
for {
|
||||
select {
|
||||
case <-ctx.Done():
|
||||
return
|
||||
case <-d.stopCh:
|
||||
return
|
||||
case entry, ok := <-entries:
|
||||
if !ok {
|
||||
return
|
||||
}
|
||||
d.handleEntry(ctx, entry)
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// Handles a single service entry.
|
||||
func (d *Discovery) handleEntry(_ context.Context, entry *zeroconf.ServiceEntry) {
|
||||
if len(entry.AddrIPv4) == 0 && len(entry.AddrIPv6) == 0 {
|
||||
slog.Debug("discovered service has no addresses", "instance", entry.Instance)
|
||||
return
|
||||
}
|
||||
|
||||
var addr string
|
||||
if len(entry.AddrIPv4) > 0 {
|
||||
addr = entry.AddrIPv4[0].String()
|
||||
} else {
|
||||
addr = entry.AddrIPv6[0].String()
|
||||
}
|
||||
|
||||
port := entry.Port
|
||||
url := fmt.Sprintf("http://%s:%d", addr, port)
|
||||
key := fmt.Sprintf("%s@%s", entry.Instance, entry.HostName)
|
||||
|
||||
d.mu.Lock()
|
||||
defer d.mu.Unlock()
|
||||
|
||||
// Check if we already know this peer
|
||||
if _, exists := d.discovered[key]; exists {
|
||||
d.discovered[key].lastSeen = time.Now()
|
||||
return
|
||||
}
|
||||
|
||||
// New peer discovered
|
||||
slog.Info("discovered nix-serve instance", "instance", entry.Instance, "url", url)
|
||||
|
||||
d.discovered[key] = &discoveredPeer{
|
||||
url: url,
|
||||
lastSeen: time.Now(),
|
||||
}
|
||||
|
||||
// Notify callback if set
|
||||
if d.onAddUpstream != nil {
|
||||
go func() {
|
||||
defer func() {
|
||||
if r := recover(); r != nil {
|
||||
slog.Error("panic in add upstream callback", "recover", r)
|
||||
}
|
||||
}()
|
||||
d.onAddUpstream(url, d.cfg.Priority)
|
||||
}()
|
||||
}
|
||||
}
|
||||
|
||||
// Removes peers that haven't been seen within the TTL period.
|
||||
func (d *Discovery) maintainPeers(ctx context.Context) {
|
||||
defer d.waitGroup.Done()
|
||||
|
||||
ticker := time.NewTicker(10 * time.Second)
|
||||
defer ticker.Stop()
|
||||
|
||||
for {
|
||||
select {
|
||||
case <-ctx.Done():
|
||||
return
|
||||
case <-d.stopCh:
|
||||
return
|
||||
case <-ticker.C:
|
||||
d.cleanupPeers()
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// Cleans up stale peer entries.
|
||||
func (d *Discovery) cleanupPeers() {
|
||||
d.mu.Lock()
|
||||
defer d.mu.Unlock()
|
||||
|
||||
now := time.Now()
|
||||
// TTL is the discovery response time; peers should re-announce periodically.
|
||||
// Use 3x TTL as the expiration window.
|
||||
expiration := d.cfg.DiscoveryTime.Duration * 3
|
||||
|
||||
for key, peer := range d.discovered {
|
||||
if now.Sub(peer.lastSeen) > expiration {
|
||||
slog.Info("removing stale peer", "url", peer.url)
|
||||
delete(d.discovered, key)
|
||||
if d.onRemoveUpstream != nil {
|
||||
go func(url string) {
|
||||
defer func() {
|
||||
if r := recover(); r != nil {
|
||||
slog.Error("panic in remove upstream callback", "recover", r)
|
||||
}
|
||||
}()
|
||||
d.onRemoveUpstream(url)
|
||||
}(peer.url)
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// Returns a list of currently discovered peer URLs.
|
||||
func (d *Discovery) DiscoveredPeers() []string {
|
||||
d.mu.RLock()
|
||||
defer d.mu.RUnlock()
|
||||
|
||||
peers := make([]string, 0, len(d.discovered))
|
||||
for _, peer := range d.discovered {
|
||||
peers = append(peers, peer.url)
|
||||
}
|
||||
return peers
|
||||
}
|
||||
|
|
@ -232,3 +232,24 @@ func (p *Prober) getOrCreate(url string) *UpstreamHealth {
|
|||
}
|
||||
return h
|
||||
}
|
||||
|
||||
// Adds a new upstream dynamically (e.g., discovered via mDNS).
|
||||
// Thread-safe. Logs the addition and begins probing.
|
||||
func (p *Prober) AddUpstream(url string, priority int) {
|
||||
p.mu.Lock()
|
||||
defer p.mu.Unlock()
|
||||
if _, exists := p.table[url]; exists {
|
||||
return
|
||||
}
|
||||
p.table[url] = &UpstreamHealth{URL: url, Priority: priority, Status: StatusActive}
|
||||
// Trigger an immediate probe in background
|
||||
go p.ProbeUpstream(url)
|
||||
}
|
||||
|
||||
// Removes an upstream from tracking (e.g., when a peer leaves the network).
|
||||
// Thread-safe. No-op if upstream was not known.
|
||||
func (p *Prober) RemoveUpstream(url string) {
|
||||
p.mu.Lock()
|
||||
defer p.mu.Unlock()
|
||||
delete(p.table, url)
|
||||
}
|
||||
|
|
|
|||
Loading…
Add table
Add a link
Reference in a new issue